PORT-AU-PRINCE, Haiti (AP) — Haiti's main airport remained closed on Tuesday, a day after violence erupted as the country swore in its new prime minister in a politically tumultuous transition.

The Clarendon police have arrested and charged 25-year-old landscaper Anthony Marshall, of Lamparth district, Trout Hall in the parish for allegedly stealing oranges from a property in his community on Sunday.

Recent studies have suggested that innate immune responses exhibit characteristics associated with memory linked to modulations in both vertebrates and invertebrates. However, the diverse evolutionary paths taken, particularly within the invertebrate taxa, should lead to similarly diverse innate immunity memory processes. Our understanding of innate immune memory in invertebrates primarily comes from studies of the fruit fly Drosophila melanogaster, the generality of which is unclear. Caenorhabditis elegans typically inhabits soil harboring a variety of fatal microbial pathogens; for this invertebrate, the innate immune system and aversive behavior are the major defensive strategies against microbial infection. However, their characteristics of immunological memory remains infantile. Here we discovered an immunological memory that promoted avoidance and suppressed innate immunity during reinfection with bacteria, which we revealed to be specific to the previously exposed pathogens. During this trade-off switch of avoidance and innate immunity, the chemosensory neurons AWB and ADF modulated production of serotonin and dopamine, which in turn decreased expression of the innate immunity-associated genes and led to enhanced avoidance via the downstream insulin-like pathway. Therefore, our current study profiles the immune memories during C. elegans reinfected by pathogenic bacteria and further reveals that the chemosensory neurons, the neurotransmitter(s), and their associated molecular signaling pathways are responsible for a trade-off switch between the two immunological memories.

Animals can sense the presence of microbes in their tissues and mobilize their own defenses by recognizing and responding to conserved microbial structures (often called microbe-associated molecular patterns (MAMPs)). Successful host defenses may kill the invaders, yet the host animal may fail to restore homeostasis if the stimulatory microbial structures are not silenced. Although mice have many mechanisms for limiting their responses to lipopolysaccharide (LPS), a major Gram-negative bacterial MAMP, a highly conserved host lipase is required to extinguish LPS sensing in tissues and restore homeostasis. We review recent progress in understanding how this enzyme, acyloxyacyl hydrolase (AOAH), transforms LPS from stimulus to inhibitor, reduces tissue injury and death from infection, prevents prolonged post-infection immunosuppression, and keeps stimulatory LPS from entering the bloodstream. We also discuss how AOAH may increase sensitivity to pulmonary allergens. Better appreciation of how host enzymes modify LPS and other MAMPs may help prevent tissue injury and hasten recovery from infection.

Knockout mouse models have been extensively used to study the antiviral activity of IFIT (interferon-induced protein with tetratricopeptide repeats). Human IFIT1 binds to cap0 (m7GpppN) RNA, which lacks methylation on the first and second cap-proximal nucleotides (cap1, m7GpppNm, and cap2, m7GpppNmNm, respectively). These modifications are signatures of “self” in higher eukaryotes, whereas unmodified cap0-RNA is recognized as foreign and, therefore, potentially harmful to the host cell. IFIT1 inhibits translation at the initiation stage by competing with the cap-binding initiation factor complex, eIF4F, restricting infection by certain viruses that possess “nonself” cap0-mRNAs. However, in mice and other rodents, the IFIT1 orthologue has been lost, and the closely related Ifit1b has been duplicated twice, yielding three paralogues: Ifit1, Ifit1b, and Ifit1c. Although murine Ifit1 is similar to human IFIT1 in its cap0-RNA–binding selectivity, the roles of Ifit1b and Ifit1c are unknown. Here, we found that Ifit1b preferentially binds to cap1-RNA, whereas binding is much weaker to cap0- and cap2-RNA. In murine cells, we show that Ifit1b can modulate host translation and restrict WT mouse coronavirus infection. We found that Ifit1c acts as a stimulatory cofactor for both Ifit1 and Ifit1b, promoting their translation inhibition. In this way, Ifit1c acts in an analogous fashion to human IFIT3, which is a cofactor to human IFIT1. This work clarifies similarities and differences between the human and murine IFIT families to facilitate better design and interpretation of mouse models of human infection and sheds light on the evolutionary plasticity of the IFIT family.

Carnosine (β-alanyl-l-histidine) and anserine (β-alanyl-3-methyl-l-histidine) are abundant peptides in the nervous system and skeletal muscle of many vertebrates. Many in vitro and in vivo studies demonstrated that exogenously added carnosine can improve muscle contraction, has antioxidant activity, and can quench various reactive aldehydes. Some of these functions likely contribute to the proposed anti-aging activity of carnosine. However, the physiological role of carnosine and related histidine-containing dipeptides (HCDs) is not clear. In this study, we generated a mouse line deficient in carnosine synthase (Carns1). HCDs were undetectable in the primary olfactory system and skeletal muscle of Carns1-deficient mice. Skeletal muscle contraction in these mice, however, was unaltered, and there was no evidence for reduced pH-buffering capacity in the skeletal muscle. Olfactory tests did not reveal any deterioration in 8-month-old mice lacking carnosine. In contrast, aging (18–24-month-old) Carns1-deficient mice exhibited olfactory sensitivity impairments that correlated with an age-dependent reduction in the number of olfactory receptor neurons. Whereas we found no evidence for elevated levels of lipoxidation and glycation end products in the primary olfactory system, protein carbonylation was increased in the olfactory bulb of aged Carns1-deficient mice. Taken together, these results suggest that carnosine in the olfactory system is not essential for information processing in the olfactory signaling pathway but does have a role in the long-term protection of olfactory receptor neurons, possibly through its antioxidant activity.

Distinct cell types emerge from embryonic stem cells through a precise and coordinated execution of gene expression programs during lineage commitment. This is established by the action of lineage specific transcription factors along with chromatin complexes. Numerous studies have focused on epigenetic factors that affect embryonic stem cells (ESC) self-renewal and pluripotency. However, the contribution of chromatin to lineage decisions at the exit from pluripotency has not been as extensively studied. Using a pooled epigenetic shRNA screen strategy, we identified chromatin-related factors critical for differentiation toward mesodermal and endodermal lineages. Here we reveal a critical role for the chromatin protein, ARID4B. Arid4b-deficient mESCs are similar to WT mESCs in the expression of pluripotency factors and their self-renewal. However, ARID4B loss results in defects in up-regulation of the meso/endodermal gene expression program. It was previously shown that Arid4b resides in a complex with SIN3A and HDACS 1 and 2. We identified a physical and functional interaction of ARID4B with HDAC1 rather than HDAC2, suggesting functionally distinct Sin3a subcomplexes might regulate cell fate decisions Finally, we observed that ARID4B deficiency leads to increased H3K27me3 and a reduced H3K27Ac level in key developmental gene loci, whereas a subset of genomic regions gain H3K27Ac marks. Our results demonstrate that epigenetic control through ARID4B plays a key role in the execution of lineage-specific gene expression programs at pluripotency exit.

Clostridium difficile is an anaerobic and spore-forming bacterium responsible for 15–25% of postantibiotic diarrhea and 95% of pseudomembranous colitis. Peptidoglycan is a crucial element of the bacterial cell wall that is exposed to the host, making it an important target for the innate immune system. The C. difficile peptidoglycan is largely N-deacetylated on its glucosamine (93% of muropeptides) through the activity of enzymes known as N-deacetylases, and this N-deacetylation modulates host–pathogen interactions, such as resistance to the bacteriolytic activity of lysozyme, virulence, and host innate immune responses. C. difficile genome analysis showed that 12 genes potentially encode N-deacetylases; however, which of these N-deacetylases are involved in peptidoglycan N-deacetylation remains unknown. Here, we report the enzymes responsible for peptidoglycan N-deacetylation and their respective regulation. Through peptidoglycan analysis of several mutants, we found that the N-deacetylases PdaV and PgdA act in synergy. Together they are responsible for the high level of peptidoglycan N-deacetylation in C. difficile and the consequent resistance to lysozyme. We also characterized a third enzyme, PgdB, as a glucosamine N-deacetylase. However, its impact on N-deacetylation and lysozyme resistance is limited, and its physiological role remains to be dissected. Finally, given the influence of peptidoglycan N-deacetylation on host defense against pathogens, we investigated the virulence and colonization ability of the mutants. Unlike what has been shown in other pathogenic bacteria, a lack of N-deacetylation in C. difficile is not linked to a decrease in virulence.

Stromal interaction molecule 1 (STIM1) plays a pivotal role in store-operated Ca2+ entry (SOCE), an essential mechanism in cellular calcium signaling and in maintaining cellular calcium balance. Because O-GlcNAcylation plays pivotal roles in various cellular function, we examined the effect of fluctuation in STIM1 O-GlcNAcylation on SOCE activity. We found that both increase and decrease in STIM1 O-GlcNAcylation impaired SOCE activity. To determine the molecular basis, we established STIM1-knockout HEK293 (STIM1-KO-HEK) cells using the CRISPR/Cas9 system and transfected STIM1 WT (STIM1-KO-WT-HEK), S621A (STIM1-KO-S621A-HEK), or T626A (STIM1-KO-T626A-HEK) cells. Using these cells, we examined the possible O-GlcNAcylation sites of STIM1 to determine whether the sites were O-GlcNAcylated. Co-immunoprecipitation analysis revealed that Ser621 and Thr626 were O-GlcNAcylated and that Thr626 was O-GlcNAcylated in the steady state but Ser621 was not. The SOCE activity in STIM1-KO-S621A-HEK and STIM1-KO-T626A-HEK cells was lower than that in STIM1-KO-WT-HEK cells because of reduced phosphorylation at Ser621. Treatment with the O-GlcNAcase inhibitor Thiamet G or O-GlcNAc transferase (OGT) transfection, which increases O-GlcNAcylation, reduced SOCE activity, whereas treatment with the OGT inhibitor ST045849 or siOGT transfection, which decreases O-GlcNAcylation, also reduced SOCE activity. Decrease in SOCE activity due to increase and decrease in O-GlcNAcylation was attributable to reduced phosphorylation at Ser621. These data suggest that both decrease in O-GlcNAcylation at Thr626 and increase in O-GlcNAcylation at Ser621 in STIM1 lead to impairment of SOCE activity through decrease in Ser621 phosphorylation. Targeting STIM1 O-GlcNAcylation could provide a promising treatment option for the related diseases, such as neurodegenerative diseases.

Infiltration of peripheral immune cells after blood-brain barrier dysfunction causes severe inflammation after a stroke. Although the endothelial glycocalyx, a network of membrane-bound glycoproteins and proteoglycans that covers the lumen of endothelial cells, functions as a barrier to circulating cells, the relationship between stroke severity and glycocalyx dysfunction remains unclear. In this study, glycosaminoglycans, a component of the endothelial glycocalyx, were studied in the context of ischemic stroke using a photochemically induced thrombosis mouse model. Decreased levels of heparan sulfate and chondroitin sulfate and increased activity of hyaluronidase 1 and heparanase (HPSE) were observed in ischemic brain tissues. HPSE expression in cerebral vessels increased after stroke onset and infarct volume greatly decreased after co-administration of N-acetylcysteine + glycosaminoglycan oligosaccharides as compared with N-acetylcysteine administration alone. These results suggest that the endothelial glycocalyx was injured after the onset of stroke. Interestingly, scission activity of proHPSE produced by immortalized endothelial cells and HEK293 cells transfected with hHPSE1 cDNA were activated by acrolein (ACR) exposure. We identified the ACR-modified amino acid residues of proHPSE using nano LC–MS/MS, suggesting that ACR modification of Lys139 (6-kDa linker), Lys107, and Lys161, located in the immediate vicinity of the 6-kDa linker, at least in part is attributed to the activation of proHPSE. Because proHPSE, but not HPSE, localizes outside cells by binding with heparan sulfate proteoglycans, ACR-modified proHPSE represents a promising target to protect the endothelial glycocalyx.

VAR2CSA is the placental-malaria–specific member of the antigenically variant Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1) family. It is expressed on the surface of Plasmodium falciparum-infected host red blood cells and binds to specific chondroitin-4-sulfate chains of the placental proteoglycan receptor. The functional ∼310 kDa ectodomain of VAR2CSA is a multidomain protein that requires a minimum 12-mer chondroitin-4-sulfate molecule for specific, high affinity receptor binding. However, it is not known how the individual domains are organized and interact to create the receptor-binding surface, limiting efforts to exploit its potential as an effective vaccine or drug target. Using small angle X-ray scattering and single particle reconstruction from negative-stained electron micrographs of the ectodomain and multidomain constructs, we have determined the structural architecture of VAR2CSA. The relative locations of the domains creates two distinct pores that can each accommodate the 12-mer of chondroitin-4-sulfate, suggesting a model for receptor binding. This model has important implications for understanding cytoadherence of infected red blood cells and potentially provides a starting point for developing novel strategies to prevent and/or treat placental malaria.

α-Linked galactose is a common carbohydrate motif in nature that is processed by a variety of glycoside hydrolases from different families. Terminal Galα1–3Gal motifs are found as a defining feature of different blood group and tissue antigens, as well as the building block of the marine algal galactan λ-carrageenan. The blood group B antigen and linear α-Gal epitope can be processed by glycoside hydrolases in family GH110, whereas the presence of genes encoding GH110 enzymes in polysaccharide utilization loci from marine bacteria suggests a role in processing λ-carrageenan. However, the structure–function relationships underpinning the α-1,3-galactosidase activity within family GH110 remain unknown. Here we focus on a GH110 enzyme (PdGH110B) from the carrageenolytic marine bacterium Pseudoalteromonas distincta U2A. We showed that the enzyme was active on Galα1–3Gal but not the blood group B antigen. X-ray crystal structures in complex with galactose and unhydrolyzed Galα1–3Gal revealed the parallel β-helix fold of the enzyme and the structural basis of its inverting catalytic mechanism. Moreover, an examination of the active site reveals likely adaptations that allow accommodation of fucose in blood group B active GH110 enzymes or, in the case of PdGH110, accommodation of the sulfate groups found on λ-carrageenan. Overall, this work provides insight into the first member of a predominantly marine clade of GH110 enzymes while also illuminating the structural basis of α-1,3-galactoside processing by the family as a whole.

RNase J enzymes are metallohydrolases that are involved in RNA maturation and RNA recycling, govern gene expression in bacteria, and catalyze both exonuclease and endonuclease activity. The catalytic activity of RNase J is regulated by multiple mechanisms which include oligomerization, conformational changes to aid substrate recognition, and the metal cofactor at the active site. However, little is known of how RNase J paralogs differ in expression and activity. Here we describe structural and biochemical features of two Staphylococcus epidermidis RNase J paralogs, RNase J1 and RNase J2. RNase J1 is a homodimer with exonuclease activity aided by two metal cofactors at the active site. RNase J2, on the other hand, has endonuclease activity and one metal ion at the active site and is predominantly a monomer. We note that the expression levels of these enzymes vary across Staphylococcal strains. Together, these observations suggest that multiple interacting RNase J paralogs could provide a strategy for functional improvisation utilizing differences in intracellular concentration, quaternary structure, and distinct active site architecture despite overall structural similarity.

α1-antitrypsin (AAT) regulates the activity of multiple proteases in the lungs and liver. A mutant of AAT (E342K) called ATZ forms polymers that are present at only low levels in the serum and induce intracellular protein inclusions, causing lung emphysema and liver cirrhosis. An understanding of factors that can reduce the intracellular accumulation of ATZ is of great interest. We now show that calreticulin (CRT), an endoplasmic reticulum (ER) glycoprotein chaperone, promotes the secretory trafficking of ATZ, enhancing the media:cell ratio. This effect is more pronounced for ATZ than with AAT and is only partially dependent on the glycan-binding site of CRT, which is generally relevant to substrate recruitment and folding by CRT. The CRT-related chaperone calnexin does not enhance ATZ secretory trafficking, despite the higher cellular abundance of calnexin-ATZ complexes. CRT deficiency alters the distributions of ATZ-ER chaperone complexes, increasing ATZ-BiP binding and inclusion body formation and reducing ATZ interactions with components required for ER-Golgi trafficking, coincident with reduced levels of the protein transport protein Sec31A in CRT-deficient cells. These findings indicate a novel role for CRT in promoting the secretory trafficking of a protein that forms polymers and large intracellular inclusions. Inefficient secretory trafficking of ATZ in the absence of CRT is coincident with enhanced accumulation of ER-derived ATZ inclusion bodies. Further understanding of the factors that control the secretory trafficking of ATZ and their regulation by CRT could lead to new therapies for lung and liver diseases linked to AAT deficiency.

Proteins in the α-macroglobulin (αM) superfamily use thiol esters to form covalent conjugation products upon their proteolytic activation. αM protease inhibitors use theirs to conjugate proteases and preferentially react with primary amines (e.g. on lysine side chains), whereas those of αM complement components C3 and C4B have an increased hydroxyl reactivity that is conveyed by a conserved histidine residue and allows conjugation to cell surface glycans. Human α2-macroglobulin–like protein 1 (A2ML1) is a monomeric protease inhibitor but has the hydroxyl reactivity–conveying histidine residue. Here, we have investigated the role of hydroxyl reactivity in a protease inhibitor by comparing recombinant WT A2ML1 and the A2ML1 H1084N mutant in which this histidine is removed. Both of A2ML1s' thiol esters were reactive toward the amine substrate glycine, but only WT A2ML1 reacted with the hydroxyl substrate glycerol, demonstrating that His-1084 increases the hydroxyl reactivity of A2ML1's thiol ester. Although both A2ML1s conjugated and inhibited thermolysin, His-1084 was required for the conjugation and inhibition of acetylated thermolysin, which lacks primary amines. Using MS, we identified an ester bond formed between a thermolysin serine residue and the A2ML1 thiol ester. These results demonstrate that a histidine-enhanced hydroxyl reactivity can contribute to protease inhibition by an αM protein. His-1084 did not improve A2ML1's protease inhibition at pH 5, indicating that A2ML1's hydroxyl reactivity is not an adaption to its acidic epidermal environment.

Cation diffusion facilitator (CDF) proteins are a conserved family of divalent transition metal cation transporters. CDF proteins are usually composed of two domains: the transmembrane domain, in which the metal cations are transported through, and a regulatory cytoplasmic C-terminal domain (CTD). Each CDF protein transports either one specific metal or multiple metals from the cytoplasm, and it is not known whether the CTD takes an active regulatory role in metal recognition and discrimination during cation transport. Here, the model CDF protein MamM, an iron transporter from magnetotactic bacteria, was used to probe the role of the CTD in metal recognition and selectivity. Using a combination of biophysical and structural approaches, the binding of different metals to MamM CTD was characterized. Results reveal that different metals bind distinctively to MamM CTD in terms of their binding sites, thermodynamics, and binding-dependent conformations, both in crystal form and in solution, which suggests a varying level of functional discrimination between CDF domains. Furthermore, these results provide the first direct evidence that CDF CTDs play a role in metal selectivity. We demonstrate that MamM's CTD can discriminate against Mn2+, supporting its postulated role in preventing magnetite formation poisoning in magnetotactic bacteria via Mn2+ incorporation.

Heme oxygenase-2 (HO2) and -1 (HO1) catalyze heme degradation to biliverdin, CO, and iron, forming an essential link in the heme metabolism network. Tight regulation of the cellular levels and catalytic activities of HO1 and HO2 is important for maintaining heme homeostasis. HO1 expression is transcriptionally regulated; however, HO2 expression is constitutive. How the cellular levels and activity of HO2 are regulated remains unclear. Here, we elucidate the mechanism of post-translational regulation of cellular HO2 levels by heme. We find that, under heme-deficient conditions, HO2 is destabilized and targeted for degradation, suggesting that heme plays a direct role in HO2 regulation. HO2 has three heme binding sites: one at its catalytic site and the others at its two heme regulatory motifs (HRMs). We report that, in contrast to other HRM-containing proteins, the cellular protein level and degradation rate of HO2 are independent of heme binding to the HRMs. Rather, under heme deficiency, loss of heme binding to the catalytic site destabilizes HO2. Consistently, an HO2 catalytic site variant that is unable to bind heme exhibits a constant low protein level and an enhanced protein degradation rate compared with the WT HO2. Finally, HO2 is degraded by the lysosome through chaperone-mediated autophagy, distinct from other HRM-containing proteins and HO1, which are degraded by the proteasome. These results reveal a novel aspect of HO2 regulation and deepen our understanding of HO2's role in maintaining heme homeostasis, paving the way for future investigation into HO2's pathophysiological role in heme deficiency response.

High-throughput sequencing of hematologic malignancies and other cancers has revealed recurrent mis-sense mutations of genes encoding pre-mRNA splicing factors. The essential splicing factor U2AF2 recognizes a polypyrimidine-tract splice-site signal and initiates spliceosome assembly. Here, we investigate representative, acquired U2AF2 mutations, namely N196K or G301D amino acid substitutions associated with leukemia or solid tumors, respectively. We determined crystal structures of the wild-type (WT) compared with N196K- or G301D-substituted U2AF2 proteins, each bound to a prototypical AdML polypyrimidine tract, at 1.5, 1.4, or 1.7 Å resolutions. The N196K residue appears to stabilize the open conformation of U2AF2 with an inter-RNA recognition motif hydrogen bond, in agreement with an increased apparent RNA-binding affinity of the N196K-substituted protein. The G301D residue remains in a similar position as the WT residue, where unfavorable proximity to the RNA phosphodiester could explain the decreased RNA-binding affinity of the G301D-substituted protein. We found that expression of the G301D-substituted U2AF2 protein reduces splicing of a minigene transcript carrying prototypical splice sites. We further show that expression of either N196K- or G301D-substituted U2AF2 can subtly alter splicing of representative endogenous transcripts, despite the presence of endogenous, WT U2AF2 such as would be present in cancer cells. Altogether, our results demonstrate that acquired U2AF2 mutations such as N196K and G301D are capable of dysregulating gene expression for neoplastic transformation.

Aspergillus terreus is an allergenic fungus, in addition to causing infections in both humans and plants. However, the allergens in this fungus are still unknown, limiting the development of diagnostic and therapeutic strategies. We used a proteomic approach to search for allergens, identifying 16 allergens based on two-dimensional immunoblotting with A. terreus susceptible patient sera. We further characterized triose-phosphate isomerase (Asp t 36), one of the dominant IgE (IgE)-reactive proteins. The gene was cloned and expressed in Escherichia coli. Phylogenetic analysis showed Asp t 36 to be highly conserved with close similarity to the triose-phosphate isomerase protein sequence from Dermatophagoides farinae, an allergenic dust mite. We identified four immunodominant epitopes using synthetic peptides, and mapped them on a homology-based model of the tertiary structure of Asp t 36. Among these, two were found to create a continuous surface patch on the 3D structure, rendering it an IgE-binding hotspot. Biophysical analysis indicated that Asp t 36 shows similar secondary structure content and temperature sensitivity with other reported triose-phosphate isomerase allergens. In vivo studies using a murine model displayed that the recombinant Asp t 36 was able to stimulate airway inflammation, as demonstrated by an influx of eosinophils, goblet cell hyperplasia, elevated serum Igs, and induction of Th2 cytokines. Collectively, our results reveal the immunogenic property of Asp t 36, a major allergen from A. terreus, and define a new fungal allergen more broadly. This allergen could serve as a potent candidate for investigating component resolved diagnosis and immunotherapy.

Bacterial low-copy-number plasmids require partition (par) systems to ensure their stable inheritance by daughter cells. In general, these systems consist of three components: a centromeric DNA sequence, a centromere-binding protein and a nucleotide hydrolase that polymerizes and functions as a motor. Type III systems, however, segregate plasmids using three proteins: the FtsZ/tubulin-like GTPase TubZ, the centromere-binding protein TubR and the MerR-like transcriptional regulator TubY. Although the TubZ filament is sufficient to transport the TubR-centromere complex in vitro, TubY is still necessary for the stable maintenance of the plasmid. TubY contains an N-terminal DNA-binding helix-turn-helix motif and a C-terminal coiled-coil followed by a cluster of lysine residues. This study determined the crystal structure of the C-terminal domain of TubY from the Bacillus cereus pXO1-like plasmid and showed that it forms a tetrameric parallel four-helix bundle that differs from the typical MerR family proteins with a dimeric anti-parallel coiled-coil. Biochemical analyses revealed that the C-terminal tail with the conserved lysine cluster helps TubY to stably associate with the TubR-centromere complex as well as to nonspecifically bind DNA. Furthermore, this C-terminal tail forms an amphipathic helix in the presence of lipids but must oligomerize to localize the protein to the membrane in vivo. Taken together, these data suggest that TubY is a component of the nucleoprotein complex within the partitioning machinery, and that lipid membranes act as mediators of type III systems.

Broad-specificity glycoside hydrolases (GHs) contribute to plant biomass hydrolysis by degrading a diverse range of polysaccharides, making them useful catalysts for renewable energy and biocommodity production. Discovery of new GHs with improved kinetic parameters or more tolerant substrate-binding sites could increase the efficiency of renewable bioenergy production even further. GH5 has over 50 subfamilies exhibiting selectivities for reaction with β-(1,4)–linked oligo- and polysaccharides. Among these, subfamily 4 (GH5_4) contains numerous broad-selectivity endoglucanases that hydrolyze cellulose, xyloglucan, and mixed-linkage glucans. We previously surveyed the whole subfamily and found over 100 new broad-specificity endoglucanases, although the structural origins of broad specificity remained unclear. A mechanistic understanding of GH5_4 substrate specificity would help inform the best protein design strategies and the most appropriate industrial application of broad-specificity endoglucanases. Here we report structures of 10 new GH5_4 enzymes from cellulolytic microbes and characterize their substrate selectivity using normalized reducing sugar assays and MS. We found that GH5_4 enzymes have the highest catalytic efficiency for hydrolysis of xyloglucan, glucomannan, and soluble β-glucans, with opportunistic secondary reactions on cellulose, mannan, and xylan. The positions of key aromatic residues determine the overall reaction rate and breadth of substrate tolerance, and they contribute to differences in oligosaccharide cleavage patterns. Our new composite model identifies several critical structural features that confer broad specificity and may be readily engineered into existing industrial enzymes. We demonstrate that GH5_4 endoglucanases can have broad specificity without sacrificing high activity, making them a valuable addition to the biomass deconstruction toolset.

Highly engineered phytases, which sequentially hydrolyze the hexakisphosphate ester of inositol known as phytic acid, are routinely added to the feeds of monogastric animals to improve phosphate bioavailability. New phytases are sought as starting points to further optimize the rate and extent of dephosphorylation of phytate in the animal digestive tract. Multiple inositol polyphosphate phosphatases (MINPPs) are clade 2 histidine phosphatases (HP2P) able to carry out the stepwise hydrolysis of phytate. MINPPs are not restricted by a strong positional specificity making them attractive targets for development as feed enzymes. Here, we describe the characterization of a MINPP from the Gram-positive bacterium Bifidobacterium longum (BlMINPP). BlMINPP has a typical HP2P-fold but, unusually, possesses a large α-domain polypeptide insertion relative to other MINPPs. This insertion, termed the U-loop, spans the active site and contributes to substrate specificity pockets underpopulated in other HP2Ps. Mutagenesis of U-loop residues reveals its contribution to enzyme kinetics and thermostability. Moreover, four crystal structures of the protein along the catalytic cycle capture, for the first time in an HP2P, a large ligand-driven α-domain motion essential to allow substrate access to the active site. This motion recruits residues both downstream of a molecular hinge and on the U-loop to participate in specificity subsites, and mutagenesis identified a mobile lysine residue as a key determinant of positional specificity of the enzyme. Taken together, these data provide important new insights to the factors determining stability, substrate recognition, and the structural mechanism of hydrolysis in this industrially important group of enzymes.

Intrinsically disordered protein domains often have multiple binding partners. It is plausible that the strength of pairing with specific partners evolves from an initial low affinity to a higher affinity. However, little is known about the molecular changes in the binding mechanism that would facilitate such a transition. We previously showed that the interaction between two intrinsically disordered domains, NCBD and CID, likely emerged in an ancestral deuterostome organism as a low-affinity interaction that subsequently evolved into a higher-affinity interaction before the radiation of modern vertebrate groups. Here we map native contacts in the transition states of the low-affinity ancestral and high-affinity human NCBD/CID interactions. We show that the coupled binding and folding mechanism is overall similar but with a higher degree of native hydrophobic contact formation in the transition state of the ancestral complex and more heterogeneous transient interactions, including electrostatic pairings, and an increased disorder for the human complex. Adaptation to new binding partners may be facilitated by this ability to exploit multiple alternative transient interactions while retaining the overall binding and folding pathway.

Iron is an essential micronutrient, and, in the case of bacteria, its availability is commonly a growth-limiting factor. However, correct functioning of cells requires that the labile pool of chelatable “free” iron be tightly regulated. Correct metalation of proteins requiring iron as a cofactor demands that such a readily accessible source of iron exist, but overaccumulation results in an oxidative burden that, if unchecked, would lead to cell death. The toxicity of iron stems from its potential to catalyze formation of reactive oxygen species that, in addition to causing damage to biological molecules, can also lead to the formation of reactive nitrogen species. To avoid iron-mediated oxidative stress, bacteria utilize iron-dependent global regulators to sense the iron status of the cell and regulate the expression of proteins involved in the acquisition, storage, and efflux of iron accordingly. Here, we survey the current understanding of the structure and mechanism of the important members of each of these classes of protein. Diversity in the details of iron homeostasis mechanisms reflect the differing nutritional stresses resulting from the wide variety of ecological niches that bacteria inhabit. However, in this review, we seek to highlight the similarities of iron homeostasis between different bacteria, while acknowledging important variations. In this way, we hope to illustrate how bacteria have evolved common approaches to overcome the dual problems of the insolubility and potential toxicity of iron.

Replication protein A (RPA) is a eukaryotic ssDNA-binding protein and contains three subunits: RPA70, RPA32, and RPA14. Phosphorylation of the N-terminal region of the RPA32 subunit plays an essential role in DNA metabolism in processes such as replication and damage response. Phosphorylated RPA32 (pRPA32) binds to RPA70 and possibly regulates the transient RPA70-Bloom syndrome helicase (BLM) interaction to inhibit DNA resection. However, the structural details and determinants of the phosphorylated RPA32–RPA70 interaction are still unknown. In this study, we provide molecular details of the interaction between RPA70 and a mimic of phosphorylated RPA32 (pmRPA32) using fluorescence polarization and NMR analysis. We show that the N-terminal domain of RPA70 (RPA70N) specifically participates in pmRPA32 binding, whereas the unphosphorylated RPA32 does not bind to RPA70N. Our NMR data revealed that RPA70N binds pmRPA32 using a basic cleft region. We also show that at least 6 negatively charged residues of pmRPA32 are required for RPA70N binding. By introducing alanine mutations into hydrophobic positions of pmRPA32, we found potential points of contact between RPA70N and the N-terminal half of pmRPA32. We used this information to guide docking simulations that suggest the orientation of pmRPA32 in complex with RPA70N. Our study demonstrates detailed features of the domain-domain interaction between RPA70 and RPA32 upon phosphorylation. This result provides insight into how phosphorylation tunes transient bindings between RPA and its partners in DNA resection.

Abnormal changes of neuronal Tau protein, such as phosphorylation and aggregation, are considered hallmarks of cognitive deficits in Alzheimer's disease. Abnormal phosphorylation is thought to precede aggregation and therefore to promote aggregation, but the nature and extent of phosphorylation remain ill-defined. Tau contains ∼85 potential phosphorylation sites, which can be phosphorylated by various kinases because the unfolded structure of Tau makes them accessible. However, methodological limitations (e.g. in MS of phosphopeptides, or antibodies against phosphoepitopes) led to conflicting results regarding the extent of Tau phosphorylation in cells. Here we present results from a new approach based on native MS of intact Tau expressed in eukaryotic cells (Sf9). The extent of phosphorylation is heterogeneous, up to ∼20 phosphates per molecule distributed over 51 sites. The medium phosphorylated fraction Pm showed overall occupancies of ∼8 Pi (± 5) with a bell-shaped distribution; the highly phosphorylated fraction Ph had 14 Pi (± 6). The distribution of sites was highly asymmetric (with 71% of all P-sites in the C-terminal half of Tau). All sites were on Ser or Thr residues, but none were on Tyr. Other known posttranslational modifications were near or below our detection limit (e.g. acetylation, ubiquitination). These findings suggest that normal cellular Tau shows a remarkably high extent of phosphorylation, whereas other modifications are nearly absent. This implies that abnormal phosphorylations at certain sites may not affect the extent of phosphorylation significantly and do not represent hyperphosphorylation. By implication, the pathological aggregation of Tau is not likely a consequence of high phosphorylation.

Programmed ribosomal frameshifting (PRF) is a mechanism used by arteriviruses like porcine reproductive and respiratory syndrome virus (PRRSV) to generate multiple proteins from overlapping reading frames within its RNA genome. PRRSV employs −1 PRF directed by RNA secondary and tertiary structures within its viral genome (canonical PRF), as well as a noncanonical −1 and −2 PRF that are stimulated by the interactions of PRRSV nonstructural protein 1β (nsp1β) and host protein poly(C)-binding protein (PCBP) 1 or 2 with the viral genome. Together, nsp1β and one of the PCBPs act as transactivators that bind a C-rich motif near the shift site to stimulate −1 and −2 PRF, thereby enabling the ribosome to generate two frameshift products that are implicated in viral immune evasion. How nsp1β and PCBP associate with the viral RNA genome remains unclear. Here, we describe the purification of the nsp1β:PCBP2:viral RNA complex on a scale sufficient for structural analysis using small-angle X-ray scattering and stochiometric analysis by analytical ultracentrifugation. The proteins associate with the RNA C-rich motif as a 1:1:1 complex. The monomeric form of nsp1β within the complex differs from previously reported homodimer identified by X-ray crystallography. Functional analysis of the complex via mutational analysis combined with RNA-binding assays and cell-based frameshifting reporter assays reveal a number of key residues within nsp1β and PCBP2 that are involved in complex formation and function. Our results suggest that nsp1β and PCBP2 both interact directly with viral RNA during formation of the complex to coordinate this unusual PRF mechanism.

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Viral infection is one environmental factor that may contribute to the initiation of pancreatic β-cell destruction during the development of autoimmune diabetes. Picornaviruses, such as encephalomyocarditis virus (EMCV), induce a pro-inflammatory response in islets leading to local production of cytokines, such as IL-1, by resident islet leukocytes. Furthermore, IL-1 is known to stimulate β-cell expression of iNOS and production of the free radical nitric oxide. The purpose of this study was to determine whether nitric oxide contributes to the β-cell response to viral infection. We show that nitric oxide protects β-cells against virally mediated lysis by limiting EMCV replication. This protection requires low micromolar, or iNOS-derived, levels of nitric oxide. At these concentrations nitric oxide inhibits the Krebs enzyme aconitase and complex IV of the electron transport chain. Like nitric oxide, pharmacological inhibition of mitochondrial oxidative metabolism attenuates EMCV-mediated β-cell lysis by inhibiting viral replication. These findings provide novel evidence that cytokine signaling in β-cells functions to limit viral replication and subsequent β-cell lysis by attenuating mitochondrial oxidative metabolism in a nitric oxide–dependent manner.

Cancer cachexia is characterized by reductions in peripheral lean muscle mass. Prior studies have primarily focused on increased protein breakdown as the driver of cancer-associated muscle wasting. Therapeutic interventions targeting catabolic pathways have, however, largely failed to preserve muscle mass in cachexia, suggesting that other mechanisms might be involved. In pursuit of novel pathways, we used untargeted metabolomics to search for metabolite signatures that may be linked with muscle atrophy. We injected 7-week–old C57/BL6 mice with LLC1 tumor cells or vehicle. After 21 days, tumor-bearing mice exhibited reduced body and muscle mass and impaired grip strength compared with controls, which was accompanied by lower synthesis rates of mixed muscle protein and the myofibrillar and sarcoplasmic muscle fractions. Reductions in protein synthesis were accompanied by mitochondrial enlargement and reduced coupling efficiency in tumor-bearing mice. To generate mechanistic insights into impaired protein synthesis, we performed untargeted metabolomic analyses of plasma and muscle and found increased concentrations of two methylarginines, asymmetric dimethylarginine (ADMA) and NG-monomethyl-l-arginine, in tumor-bearing mice compared with control mice. Compared with healthy controls, human cancer patients were also found to have higher levels of ADMA in the skeletal muscle. Treatment of C2C12 myotubes with ADMA impaired protein synthesis and reduced mitochondrial protein quality. These results suggest that increased levels of ADMA and mitochondrial changes may contribute to impaired muscle protein synthesis in cancer cachexia and could point to novel therapeutic targets by which to mitigate cancer cachexia.

Pectins are a major dietary nutrient source for the human gut microbiota. The prominent gut microbe Bacteroides thetaiotaomicron was recently shown to encode the founding member (BT1017) of a new family of pectin methylesterases essential for the metabolism of the complex pectin rhamnogalacturonan-II (RG-II). However, biochemical and structural knowledge of this family is lacking. Here, we showed that BT1017 is critical for the metabolism of an RG-II–derived oligosaccharide ΔBT1017oligoB generated by a BT1017 deletion mutant (ΔBT1017) during growth on carbohydrate extract from apple juice. Structural analyses of ΔBT1017oligoB using a combination of enzymatic, mass spectrometric, and NMR approaches revealed that it is a bimethylated nonaoligosaccharide (GlcA-β1,4-(2-O-Me-Xyl-α1,3)-Fuc-α1,4-(GalA-β1,3)-Rha-α1,3-Api-β1,2-(Araf-α1,3)-(GalA-α1,4)-GalA) containing components of the RG-II backbone and its side chains. We showed that the catalytic module of BT1017 adopts an α/β-hydrolase fold, consisting of a central twisted 10-stranded β-sheet sandwiched by several α-helices. This constitutes a new fold for pectin methylesterases, which are predominantly right-handed β-helical proteins. Bioinformatic analyses revealed that the family is dominated by sequences from prominent genera of the human gut microbiota, including Bacteroides and Prevotella. Our re-sults not only highlight the critical role played by this family of enzymes in pectin metabolism but also provide new insights into the molecular basis of the adaptation of B. thetaiotaomicron to the human gut.

Peptidoglycan (PG) is an essential constituent of the bacterial cell wall. During cell division, the machinery responsible for PG synthesis localizes mid-cell, at the septum, under the control of a multiprotein complex called the divisome. In Escherichia coli, septal PG synthesis and cell constriction rely on the accumulation of FtsN at the division site. Interestingly, a short sequence of FtsN (Leu75–Gln93, known as EFtsN) was shown to be essential and sufficient for its functioning in vivo, but what exactly this sequence is doing remained unknown. Here, we show that EFtsN binds specifically to the major PG synthase PBP1b and is sufficient to stimulate its biosynthetic glycosyltransferase (GTase) activity. We also report the crystal structure of PBP1b in complex with EFtsN, which demonstrates that EFtsN binds at the junction between the GTase and UB2H domains of PBP1b. Interestingly, mutations to two residues (R141A/R397A) within the EFtsN-binding pocket reduced the activation of PBP1b by FtsN but not by the lipoprotein LpoB. This mutant was unable to rescue the ΔponB-ponAts strain, which lacks PBP1b and has a thermosensitive PBP1a, at nonpermissive temperature and induced a mild cell-chaining phenotype and cell lysis. Altogether, the results show that EFtsN interacts with PBP1b and that this interaction plays a role in the activation of its GTase activity by FtsN, which may contribute to the overall septal PG synthesis and regulation during cell division.

Environmental factors, such as viral infection, are proposed to play a role in the initiation of autoimmune diabetes. In response to encephalomyocarditis virus (EMCV) infection, resident islet macrophages release the pro-inflammatory cytokine IL-1β, to levels that are sufficient to stimulate inducible nitric oxide synthase (iNOS) expression and production of micromolar levels of the free radical nitric oxide in neighboring β-cells. We have recently shown that nitric oxide inhibits EMCV replication and EMCV-mediated β-cell lysis and that this protection is associated with an inhibition of mitochondrial oxidative metabolism. Here we show that the protective actions of nitric oxide against EMCV infection are selective for β-cells and associated with the metabolic coupling of glycolysis and mitochondrial oxidation that is necessary for insulin secretion. Inhibitors of mitochondrial respiration attenuate EMCV replication in β-cells, and this inhibition is associated with a decrease in ATP levels. In mouse embryonic fibroblasts (MEFs), inhibition of mitochondrial metabolism does not modify EMCV replication or decrease ATP levels. Like most cell types, MEFs have the capacity to uncouple the glycolytic utilization of glucose from mitochondrial respiration, allowing for the maintenance of ATP levels under conditions of impaired mitochondrial respiration. It is only when MEFs are forced to use mitochondrial oxidative metabolism for ATP generation that mitochondrial inhibitors attenuate viral replication. In a β-cell selective manner, these findings indicate that nitric oxide targets the same metabolic pathways necessary for glucose stimulated insulin secretion for protection from viral lysis.

Africa Aware: Relations between Ethiopia and Sudan Audio bhorton.drupal 9 April 2022

This episode of Africa Aware examines the relationship between Ethiopia and Sudan.

Ahmed Soliman provides an overview of the Africa Programme’s work on cross-border conflict as part of the XCEPT project.

First, we speak to Kholood Khair on the steady deterioration in relations between Sudan and Ethiopia. Then Abel Abate Demissie discusses how recent political developments in Ethiopia and Sudan have impacted relations between the two countries.

This podcast was produced with support from the Cross-Border Conflict Evidence, Policy and Trends (XCEPT) project, funded by UK Aid from the UK government. The views expressed do not necessarily reflect the UK government’s official policies.

It is also part of a series of outputs on Ethiopia’s political transition.

Towards just transition in Africa: Green financing for urban energy solutions and job creation 9 June 2022 — 7:30AM TO 11:00AM Anonymous (not verified) 18 May 2022 Nairobi and online

This event explores the major openings and potential impediments to the development of a just transition policy in Africa.

Global climate policies towards a ‘just transition’ under the Paris Agreement should also align with and support African states’ national sustainable development priorities. In particular, the need for decent and fair job creation and the establishment of sufficient, resilient and sustainable power supply, accessible to all, and efficient energy use.

Achieving green growth requires innovative and more accessible financing models, especially as wealthy nations’ financial pledges have fallen short. Ahead of the ‘African COP27’ set to take place in Egypt in November 2022, there is a need for transformational strategic thinking and context-specific action from African governments, civil society, businesses and financiers in their green financing demands and national implementation plans.

Sustainable urban energy solutions represent a critical zone of opportunity for the development of new and more reliable green finance pathways. Africa’s rapidly expanding cities present a significant economic opportunity and source of growth. However, urban centres are also where income and energy inequalities are at their starkest. The acceleration of sustainable energy generation and use could have a transformative impact on SMEs and livelihoods across value chains.

At this event, participants will discuss the major openings and potential impediments to the development of a credible ‘just transition’ policy in Africa towards net zero goals, with a particular focus on establishing and enhancing links between green financing innovation, employment creation, sustainable power supply and generation, and sustainable energy usage and consumption in an urban environment.

This event is held in partnership with the Pan African Climate Justice Alliance (PACJA). It is part of a series on Towards Just Transition: Connecting Green Financing and Sustainable Job Creation in Africa, supported by the Chatham House Sustainability Accelerator.

This event will be held in English and French with simultaneous interpretation.

War in Ukraine: The world reaction - Brazil and Africa Audio NCapeling 9 June 2022

The ninth episode of our podcast mini-series examines perspectives from Brazil and the Africa region and the impact on their relations with Russia.

How have Brazil and Africa reacted to the war in Ukraine? With impending elections in Brazil, how is President Bolsonaro’s relationship with Putin received by the public? How will food insecurity affect African nations’ response to the war?

This episode was produced by David Dargahi and Anouk Millet of Earshot Strategies on behalf of Chatham House.

How is the war in Ukraine affecting perceptions of Russia in Africa? Explainer Video NCapeling 10 June 2022

Aanu Adeoye outlines how the invasion of Ukraine is affecting perceptions of Russia across the Africa region.

He says the voting patterns at the United Nations (UN) shows that the majority of African countries are unhappy about Russia’s actions, but there is not a united voice as there is in the European Union (EU) and North America.

Certain countries are heavily influenced by historical ties with Russia going back to the Soviet era and their own struggles for liberation, while others tend to remain non-aligned whenever possible.

Towards just transition in Africa: Green financing for nature-based solutions and rural resilience 21 July 2022 — 9:30AM TO 1:00PM Anonymous (not verified) 30 June 2022 Libreville and online

This hybrid event in Libreville explores just transition policy and green financing for nature-based solutions, with a particular focus on the integration of job creation priorities in conservation and rural resilience.

Global climate policies towards a ‘just transition’ under the Paris Agreement should align with and support African states’ national sustainable development priorities – in particular, the need for decent and fair job creation, as well as resilient and sustainable land, environment, and ecosystem management policies.

Achieving green growth requires innovative and more accessible financing models, especially as wealthy nations’ financial pledges have fallen short. Ahead of the ‘African COP27’ set to take place in Egypt in November 2022, there is a need for transformational strategic thinking and context-specific action from African governments, civil society, businesses and financiers, in their green financing demands and national implementation plans.

Preservation of biodiversity and nature is not only critical in the global fight against climate change but is also vital for conservation-based economic development. Natural capital stocks, such as terrestrial and marine ecosystems and biodiversity, produce benefits that support societal and individual well-being and economic prosperity, such as clean air, fresh water, regulation of water flows and pollination of crops – while also acting as important carbon sinks. Financing environmental protection must go beyond compensation and contribute to creating fair social and economic conditions for incentivizing conservation.

At this hybrid event in Libreville, participants will discuss green financing for nature-based solutions, particularly the integration of plans for job creation in conservation and rural resilience within just transition planning.

This event is part of a series on Towards Just Transition: Connecting Green Financing and Sustainable Job Creation in Africa, supported by the Chatham House Sustainability Accelerator.

This event will be held in French and English with simultaneous interpretation.

This event will also be broadcast live on the Chatham House Africa Programme’s Facebook page.

Why Ethiopia must close its political gender gap The World Today mhiggins.drupal 29 July 2022

Women urgently need to gain access to high office if the country hopes to survive, say Hilina Berhanu Degefa and Emebet Getachew.

At the end of 2021, Prime Minister Abiy Ahmed’s government announced the formation of a three-year national dialogue to address Ethiopia’s political crisis, looking at the ongoing civil war and conflict, inflation, unemployment, drought and other urgent domestic issues. 

But, while efforts have been made to ensure the participation of women in this dialogue, it must be more than symbolic otherwise gaps in meaningful gender inclusion could have significant implications on the very survival of the country.
 
One of the challenges for meaningful inclusion is that Ethiopia is a highly patriarchal society. Patriarchal norms and practices permeate all aspects of the country’s social, economic and political life. Women constitute over half of the Ethiopian population and represent 41 per cent of the national parliament.

Nevertheless, most political parties, including those with liberal credentials, are exclusively governed by men, with women taking almost no part in key decision-making processes. As a result, women are relegated to the margins of political and economic activities. 

Though there has been little systematic study of the structural challenges faced by Ethiopian women in politics, women members of political parties encounter many barriers, including political violence, male-coded norms and sexist discourses across Ethiopian society.
 
The nature and scale of political violence perpetrated against women is particularly disempowering and affects their ability to participate in political spaces.

While attitudes to gender equality, sexual violence and gender discrimination are often trivialized, they remain ever-present threats in women’s lives. As late as 2016, a significant minority of men still believed wife-beating to be justified in certain situations. Even when women overcome social pressure to pursue their political ambitions, patriarchal views and practices within political party structures about the role of women significantly undermine their active participation and engagement. 

The political space is even more inaccessible to women with disabilities and in conflict and climate-related crises such as among internally displaced people and in pastoral communities. Male-coded norms ingrained at both party and community levels remain a significant concern. Specifically, sex in exchange for candidacy, inconsiderate working schedules affecting women with children and denial of access to equal information and financial resources are frequently reported as major internal hurdles among political parties.

Closing the gender gap could offer Ethiopia a new beginning

Many political initiatives designed to tackle these gender imbalances often have been driven by short-term political considerations without proper gender-gap assessment and policy analysis. In most cases, the authorities have viewed gender-targeted reforms as acts of benevolence, dispensed by the government, without adopting the legal and financial measures necessary to ensure sustainability and impact.
 
Take, for example, Abiy’s appointment of a 50:50 gender-balanced cabinet in 2018. At the time, much was made about its transformative potential, with the prime minister attracting widespread global approval. Yet, a cabinet reshuffle in 2021 reduced female representation to 36.3 per cent, with far less scrutiny or accountability.

This indicates that gender equality in Ethiopia is not considered a priority but rather an endeavour for more opportune, ‘stable’ times. Without thorough measures that create the conditions for real change, the aspiration of having a gender-balanced cabinet will always be challenging to translate into lasting equal representation.
 
The proposed national dialogue presents an ideal opportunity for Ethiopian women to begin reshaping attitudes and closing the gender gap through their inclusion and participation in the political process. To do so, three issues must be addressed.
 
First, the varying rights of women need to be consolidated, including on identity, constitutional reform and economic issues .

Second, gender equality considerations must be absorbed into mainstream political discourse at all levels.

Third, the experiences of women in the recent war, other ongoing conflicts and past and lingering legacies of political violence targeting women from specific communities, must be acknowledged and remedied. 

If Ethiopia is indeed serious about addressing its asymmetric gender power dynamics, this national dialogue provides an excellent opportunity to begin the process. Genuine participation of women as independent actors, with their own agency, could offer Ethiopia a new beginning.

Will Africans’ calls for better democracy be met? The World Today mhiggins.drupal 29 July 2022

Voters want the continent’s ageing leaders to step aside to usher in a new age of political engagement and robust democracy, say the experts of Afrobarometer.

Across Africa, recent years have been marked by both encouraging democratic highs and troubling anti-democratic lows. Notable advances from last year include the Gambia’s successful presidential election, a ruling-party transition in Zambia and the first democratic transfer of power in Niger. In the lead up to this, add Malawi’s retake of its flawed presidential election in 2020 and an earlier succession of oustings of long-serving autocrats in Sudan, Zimbabwe and the Gambia. 

Contrast these gains, though, with setbacks elsewhere, including increasing restrictions on opposition parties in Benin, Senegal and Tanzania; the use of violence and intimidation during elections in Côte d’Ivoire and Uganda; and military coups, with the latest in Burkina Faso this year and last year in Chad, Mali, Sudan and Guinea.

These contradictory developments join dire warnings from experts that democracy is losing ground on the continent. But what can we learn about the state of democracy on the continent from Africans themselves?

Afrobarometer, a pan-African, non-partisan research network, has been surveying people about their views on democracy, governance and quality of life for more than 20 years. After interviewing nearly 50,000 citizens across 34 countries during Afrobarometer Round 8, which spans 2019-2021, we find that despite the efforts of some leaders to undermine democratic norms, Africans remain committed to democracy and democratic institutions.

They believe that the military should stay out of politics, that political parties should freely compete for power, that elections are an imperfect but essential tool for choosing their leaders, and that it is time for the old men who cling to power to step aside.

But their political reality falls short of these expectations. The perception of widespread and worsening corruption is particularly corrosive, leaving people increasingly dissatisfied with political systems that are yet to deliver on their aspirations to live in societies that are democratically and accountably governed. And although citizens find myriad ways to voice their concerns, they feel that their governments are not listening.

Simply put, Africans want more democratic and accountable governance than they think they are getting.

Africans’ democratic aspirations

Over the past decade, democracy watchers have been alarmed by declining trends in Africa. Concerns have been exacerbated in the past two years as some governments have taken advantage of the Covid pandemic to limit freedoms, restrict fair campaigning or postpone elections. Activists fear that supposedly temporary rollbacks in hard-won governance reforms could become permanent.

But for the most part, African citizens remain committed to democracy and democratic institutions. Across 30 countries that Afrobarometer has surveyed consistently since Round 5 (2011–2013), most indicators are strong and quite steady.

For example, seven in 10 Africans say that ‘democracy is preferable to any other kind of government’. While this is down modestly from 73 per cent a decade ago, more specific indicators seem to affirm popular commitment to democracy. Large and steady majorities consistently reject authoritarian alternatives, including one-person or ‘strongman’ rule (82 per cent), one-party rule (77 per cent) and military rule (75 per cent), which is clearly rejected even in many of the countries rocked by recent military coups.

Africans also express strong support for a limit to presidential terms, a feature of democratic governance that researchers and activists argue nurtures political participation, demonstrates that change via the ballot box is possible, and reduces the risk of personality cults, authoritarianism, corruption and coups. Across 34 countries, an average of 76 per cent favour limiting their presidents to two terms, including a majority (54 per cent) who ‘strongly’ support this rule. Term limits enjoy majority support in every surveyed country. 

The public’s democratic commitment is undergirded by strong and in some cases growing support for core democratic institutions. Support for multiparty competition and parliamentary oversight of leaders remains steady, while expectations that governments should be accountable to the courts have increased significantly over the past decade.

In addition, growing numbers of people say it is more important to have a government that is accountable to the people rather than one that just ‘gets things done’, an especially strong indicator of deepening commitment to democratic norms among citizens. 

Trouble at the polling booth

Elections remain a central, though controversial, institution of democracy for Africans. They have served as the foundation for real change, as in Zambia last year. But in other cases, such as Uganda’s January 2021 poll, they have been marred by violence and human rights abuses, as well as the weaponization of Covid to justify restrictions on campaigning.

The public is also sceptical about the capacity of elections to bring about real change: fully 50 per cent say they do not think elections are effective in enabling voters ‘to remove from office leaders who do not do what the people want’.

At the same time, large majorities report positively on their country’s election environment. Asked about their most recent election, at least eight in 10 say they did not observe intimidation (87 per cent) or interference (81 per cent) by security forces and did not fear violence (80 per cent).

We must keep in mind that these encouraging averages can obscure deep problems in some countries. For example, while only 3 per cent of Namibians say votes are ‘often’ not counted fairly, between a quarter and one-third cite inaccurate counts as a frequent problem in Zimbabwe, Sudan and Gabon. 

In addition, confidence in the fairness of the media environment is drastically lower, on average just 36 per cent.

But perhaps most importantly, almost nine in 10 Africans (87 per cent) say they are free to vote as they choose, including sizeable majorities in every surveyed country. And a solid majority of 63 per cent rate their most recent election as completely or mostly free and fair. 

All of this may help to explain still-strong support for competitive elections as the best system for selecting leaders. A robust three-quarters confirm their commitment to elections, though this has fallen slightly over the past decade, probably reflecting disillusionment with electoral processes that are too often torn by violence and produce contested results. 

A growing number of people may also be recognizing that elections, especially poor-quality ones, are not enough to guarantee democracy and better governance, and that a healthy democracy must include such other features as government accountability, respect for the rule of law, responsiveness and citizen participation.

The ‘democratic disappointment’ gap

To what extent does political reality align with Africans’ democratic aspirations? Our findings suggest that it is falling well short of expectations.

While a slim majority has steadily reported that their country is a ‘full democracy’ or one ‘with minor problems’ over the past decade, satisfaction, however, has dropped to 43 per cent in that time. 

What explains this growing dissatisfaction? Other indicators of democratic supply offer some clues. While ratings of election quality have held steady, favourable public assessments of presidential accountability to parliament and to the courts have both declined.

The rising scourge of corruption

But one of the most significant driving factors may be burgeoning corruption, a trend that appears to parallel declining democratic satisfaction. On average across 34 countries, around six in 10 say both that corruption in their country increased over the past year, and that their government is doing a poor job of controlling it.

These perceptions matter. Over time, when perceptions of corruption rise or fall, levels of dissatisfaction with democracy tend to follow suit. 

In South Africa, dissatisfaction with democracy grew steadily alongside scandals involving President Jacob Zuma, and has continued to rise under his successor, Cyril Ramaphosa, whose office has been tainted by ‘Farmgate’ and a major Covid-relief scandal. The ‘Fishrot’ scandal in Namibia has had similar consequences.

Are governments listening?

African citizens are raising their voices, calling on their governments to fulfil their democratic aspirations. Since April 2017, the Carnegie Endowment for International Peace has recorded more than 70 episodes in 35 African countries of protests focused on issues ranging from demands for democracy in eSwatini to resisting police brutality, presidential third-term attempts and Covid restrictions. 

Citizen participation and government responsiveness are cornerstones of democracy. But are governments listening?

Voting is the most obvious and popular way for citizens to express themselves, and Africans take advantage of this opportunity. Two-thirds said they voted in their most recent national election. But elections occur only occasionally, and they force individuals to compress a wide array of views into very few choices. How do Africans find their voice during the long intervals between elections?

Many invest in personal efforts to act as agents of change. In fact, nearly half say they joined with others to raise an issue at least once in the past year, and a third contacted a political leader. A quarter report they acted with others to request government action. Less common but still important modes of engagement include asking for help from or lodging a complaint with government, contacting the media, and joining a demonstration.

These robust levels of citizen engagement suggest that people feel they can make a difference. Unfortunately, decision-makers aren’t always receptive or responsive to citizen voices. Less than a quarter of people think local government officials listen to them – and even fewer think their members of parliament do. 

What is more troubling is that fully two-thirds say they are at risk of retaliation or some form of negative consequences if they take action by reporting incidents of corruption. 

Lack of government responsiveness and respect for popular voices may have direct implications for both citizen engagement and citizen satisfaction. For example, we find that people are more likely to contact leaders or take other actions to solve problems if they believe that government officials respect and listen to them; that they will get a response if they raise an issue; and if they do not need to fear retaliation. 

Similarly, when we compare country averages for government responsiveness to the percentage of citizens who are satisfied with democracy, we again find positive associations. 

When governments are responsive, citizens are more likely to engage in addressing community needs and to be satisfied with their political system and optimistic about the future. Respectful and responsive governance has the potential to spur citizen action to solve critical development challenges – and may be the cure for what ails democracy.

Now is the moment to launch an African vaccine industry The World Today mhiggins.drupal 31 July 2022

The continent plans to make 60 per cent of its vaccines by 2040. After the failure of the world to help in the pandemic, it’s high time, says Ngozi Erondu.

The lack of an African vaccine industry has been a glaring concern for decades. Before the pandemic, 99 per cent of Africa’s vaccines were manufactured outside the continent. As well as endangering the lives of millions, this situation has inhibited social and economic progress on the continent.

In response, the Africa Centres for Disease Control and Prevention (Africa CDC) has undertaken an ambitious plan, outlined in the Partnerships for African Vaccine Manufacturing (PAVM) Framework for Action, to develop the nascent African vaccine manufacturing sector into an end-to-end industry by 2040. The framework aims to raise the share of African-manufactured vaccines used across the continent to 60 per cent by 2040, or the equivalent to up to 1.7 billion doses annually.

Seven of every 10 vaccines used in Africa are currently donated through Gavi, the Vaccine Alliance. Most are administered within childhood immunization programmes and are largely manufactured either in India, or by  multinational vaccine manufacturers in North America or Japan.

Vaccine donations have inhibited the development in Africa of vaccines and other countermeasures against diseases.

Though the Ebola virus was discovered in Central Africa in 1976, vaccine development was not adequately funded until it emerged in Europe in 2014. Human monkeypox resurfaced in Nigeria in 2017, yet the global Coalition for Epidemic Preparedness Innovations only targeted it for vaccine development in July this year.

The pandemic highlighted Africa’s fatal dependency on imported vaccines. Only 20 per cent of Africans are fully vaccinated against Covid-19, due to the failure of countries in the Global North to ensure the equitable distribution of vaccines via the COVAX facility to 40 per cent of the world’s most vulnerable people. 

The pandemic also confirmed that Africa could not rely on fellow states of the Global South. At the height of the Delta variant outbreak in early 2021, India halted vaccine exports to Africa, where only 1.5 per cent of the population had at that time received any vaccine doses.

After decades of discussions, there are signs that Africa could soon succeed in creating its own vaccine industry. First, the 55-member African Union is in the process of establishing the African Medicines Agency, a regional regulatory body. 
 

‘The new public health order’

Additionally, the African Export-Import Bank and African Development Bank (AfDB) have established a foundation to provide financial and strategic support for the development of the pharmaceutical industry and the consolidation of regional vaccination programmes in Africa (the foundation would potentially negotiate intellectual property rights and licensing issues but that remains to be seen).

Second, studies show there is an emerging middle class in Africa. In a 2011 report by the AfDB, this was estimated at some 56 million households. Potentially, this means many people will be able to buy vaccines and medicines made in Africa.

About a third of African countries currently pay for their vaccine needs. According to PAVM forecasts, the value of the total African market could reach between $3 billion and $17 billion by 2040.

The recent entry into effect of the African Continental Free Trade Area should also prove conducive to African vaccine development. Through economic integration, free movement and harmonized regional standards, countries that invest in their biopharmaceutical and medical technology sectors may attract employees, regional and international businesses, and investment. Further, the pandemic has encouraged people to relocate to countries with, or planning for, universal healthcare.

Building an African pharmaceutical industry from the ground up could take much longer than two decades and cost tens of billions of dollars. Nevertheless, the moment seems ripe, and timely support has been forthcoming from influential regional actors, including Rwandan President Paul Kagame, South Africa’s Cyril Ramaphosa, and private sector business executives, including the Zimbabwean-born billionaire Strive Masiyiwa.

With a pandemic treaty embedding equity in prevention, preparedness and response some way off, and given the limitations surrounding the recent World Trade Organization compromise on the TRIPS waiver – which temporarily waives Covid-19 vaccine patent protections for poorer countries – it is doubly important for Africa to build up its own pharmaceutical industry and emergency systems. 

In 2021, John Nkengasong, then director of Africa CDC, wrote of the necessity of a post-pandemic ‘new public health order’ for Africa. Such a change may threaten the global health organizations, industries and institutes who derive payment from ‘saving Africa’ during emergencies. Additionally, through strengthening Africa CDC, other actors such as the World Health Organization may find that they have a diminished strategic role on the continent.
 
While Africa should not dismiss these valuable and long-standing partnerships, it must take the opportunity to advance its interests and to assume leadership in this important area.

A booming tech sector can unleash pan-African trade The World Today mhiggins.drupal 31 July 2022

The new African Continental Free Trade Area must embrace hyperscale data centres, cross-border digital payments and other innovations to realise its potential.

The Africa Continental Free Trade Area (AfCFTA) not only lays the groundwork for a single market across the continent, it can act as a driving force to unleash the full potential of the technology revolution that is under way across the African continent. 

To help achieve this, the AfCFTA must go beyond simply lowering barriers to the movement of goods and services, to what the World Bank calls an ‘FDI [foreign direct investment] deep scenario’. This requires harmonizing policies on investment, competition, intellectual property rights and e-commerce to encourage FDI at a greater scale. 

The World Bank estimates that the AfCFTA could increase income across the continent by 7 per cent by 2035 (an additional $445 billion), mainly by boosting intra-regional trade in manufactured goods and lifting approximately 40 million people from extreme poverty. Under an FDI deep scenario, the projected income growth jumps to 9 per cent by 2035, supporting 50 million people out of extreme poverty. 

The initial focus of the AfCFTA is on movement of goods and services and the associated financial flows through the establishment of the Pan-African Payment and Settlement System (PAPSS), a technology that enables instant local currency payment across Africa without first converting to a hard currency. In addition, harmonizing policies and easing the movement of data could enable technology to accelerate the anticipated AfCFTA income growth.

Global venture capital is pouring in

There is no doubt the African tech industry is growing. In 2021, 681 African technology companies raised $5.2 billion in equity venture funding, up from $2 billion in 2019, according to Partech Partners’ annual Africa Tech Venture Capital report. 

It is understandable why the industry has attracted global venture capital. While tech businesses are often initially focused on meeting needs in their home markets, most have a strong desire to tap into the pan-African market, with its 1.3 billion consumers across 54 countries and a combined GDP of $3.4 trillion. This in turn should attract global venture capital to invest in Africa. 

The AfCFTA has created a framework for technology-led companies to scale across the continent in a way that will impact digital infrastructure, logistics, energy and much else. For example, Africa’s hyperscale data centre capacity would benefit from the ability to locate centres in the lowest cost jurisdiction with the best energy availability and to use that to power cloud storage across the continent.

Yet various regulatory constraints, including the desire for each state to own its population’s data on local servers, prevent that. As a result, African data centres are less competitive than those in America and China. 

Similarly, logistics and other sectors would be transformed if the information on goods in transit, such as digital customs documentation, could move easily across borders while being tracked across all 54 countries. Financial services would also benefit from the ability to pay across borders in a low-cost, frictionless way.

Fintech companies should be encouraged to build technology solutions linking to PAPSS and other initiatives to accelerate the adoption-of-use cases that PAPSS supports – such as intra-Africa instant payment, embedded finance and remittances services.

AfCFTA may also unlock mergers and acquisitions (M&A) activity among African and international firms. Technology companies are using M&A to enter new markets, as the international payments platform Stripe did when it acquired the Nigerian business Paystack, and the payments business MFS Africa did when it took over the fintech start-up Baxi. 

Governments and regulators must support innovation

Given the difficulty of a country-by-country organic growth strategy across Africa, M&A is likely to increase in various technology sectors over the next few years. With the anticipated ease of doing business that the AfCFTA could facilitate, we are likely to witness further welcome consolidation, creating larger corporates that create more jobs and increase tax revenues. 

To unlock the benefits that technology will bring, governments and regulators need to play a supportive role in encouraging innovation. They will need to ensure the appropriate consumer protections are in place without stifling creativity through regulation, inefficiencies or rent-seeking. 

At the same time, governments and regulators should not permit themselves to be held to ransom by dominant incumbents, such as banks and mobile operators in the fintech space, at the expense of stifling technology companies looking to disrupt their respective industries. 

Only then will the AfCFTA allow Africa to benefit from its tech potential. 

Risana Zitha writes this article in a personal capacity

Why Africa needs to be in space The World Today mhiggins.drupal 1 August 2022

From agriculture and navigation to banking and tele-education, satellite technology can have a huge impact on rapidly developing societies, says Val Munsami.

Africa’s socio-economic and environmental development is widely acknowledged as being crucial to its growth and long-term sustainability – and the prosperity of its more than one billion residents. 

Increasingly, though, attention is also turning to the contribution that the space industry can make to progress on the continent. Space-based products and services have a critical role to play in meeting national and continental priorities, as underpinned by the UN’s Sustainable Development Goals and the African Union’s Agenda 2063 – the bloc’s strategic framework for development, democracy and peace. 

With this in the mind of policymakers, the African Union’s space policy and strategy is embedded in Agenda 2063 as one of its 15 key programmes. It guides the sector’s development and the nascent African Space Agency, to become operational later this year from its headquarters in Egypt.

The continental agency is expected to leverage the benefits of space science and technology for socio-economic and environmental development. It will lead on bridging the space divide, especially for those countries that do not have a focus on, or activities in, space science and technology – and simultaneously inject some momentum into improving capabilities of existing national space programmes.

The African Union’s commitment to space has accelerated the growth of the African space industry. More than 20 national space agencies or space-related institutions have been established on the continent over the past five or so years. 

Our modern lifestyles are intimately dependent on space products and services. Meteorological and communication satellites are placed in geostationary orbits at an altitude of 36,000km above the equator. At this point above the Earth, they complete one orbit every 24 hours in the direction of the planet’s rotation, appearing, essentially, motionless – and providing a constant gaze on the same geographic location.

They provide a wealth of information that fuels the everyday services we take for granted, but that are essential for our everyday lives, from health to education to the economy.

From their vantage point, geostationary orbit satellites provide our daily weather reports, monitor climate-related cycles and offer a platform for near-instantaneous communications across the globe to relay multimedia, live sporting events and up-to-the-minute global news. 

This lightning-fast communication is also indispensable for tele-education and tele-medicine, by which professionals in urban areas can deliver educational content and health services to rural schools and clinics, respectively. Banking transactions also rely on telecommunication satellites to communicate between an automated teller machine and the data servers located at the bank. 

How satellites can detect disease

Other satellites are placed in low Earth orbits. These complete on average one polar orbit around the Earth every 100 minutes. Because the planet rotates across the plane of the orbit, such a satellite eventually covers the whole Earth, which is immensely useful for remote sensing and navigation and positioning applications. 

Remote sensing applications provide a myriad of products and services, including monitoring the state of our natural resources, observing ship traffic in our coastal economic zones and providing information for precision farming that can help a farmer decide, for example, when to irrigate and how much fertilizer to use.

They can also detect changes that might indicate encroaching water-borne diseases, aid peacekeeping missions and help ensure public safety and security. Navigation applications are vital for aviation and marine navigation, whereas positioning applications are important for safety-of-life services. 

Another way that positioning applications in developing countries are put to good use is the assignment of geolocation addresses to dwellings in informal settlements where postbox addresses do not exist. This then allows the overlaying of key vector data about populations on to geophysical base maps. This type of data is vital for town planning in terms of how many schools and clinics are needed to serve the population, and the extent of the road, water, sanitation and electrical infrastructure needed.

The rich source of information derived from satellites, overlaid with in-situ data, is vital for evidence-based decision and policymaking. Datasets accessed from historical archives can be used to observe the time evolution of environmental and statistical data. 

When policy decisions are taken, we can utilize the same satellite and in-situ platforms to monitor progress after their implementation. The utility of data to inform decision-making is being enhanced through the adoption of AI and big-data analytics, which is placing key information at our disposal in near real time. 

It is therefore not surprising to notice the increasing focus on space science and technology activities on the continent. However, to ensure the effective uptake and utilization of space products and services, certain building blocks are needed to establish robust national and regional space ecosystems. 

Africa’s route into space

These ecosystems must include four primary elements to function: the human capital required to establish and operate the space initiatives; a significant industry base to capitalize on the commercial aspects of the space sector; the requisite infrastructure needed to support the space value chain; and international cooperation to ensure knowledge transfer and diffusion – so that we don’t have to reinvent the wheel.

The applications and problem-solving innovations provided by space products and services are endless. To take advantage of this, Africa needs strong governance and institutional architectures. 

The evolution of the space ecosystem on the continent must be premised on key instruments such as a space policy – which areas to focus on and why – and a space strategy that outlines which programmes and performance indicators to pursue. 

The conceptualization of a space ecosystem is by no means a simple endeavour and there is certainly a dearth of skills and experience on the African continent to establish effective and relevant space ecosystems. 

There are many institutions leading efforts to build space capacity and skills on the continent, such as the International Space University in France, which offers programmes that provide a holistic overview of the complex global space sector, and the African Space Leadership Institute, which has been recently created to develop capacity in space policy, law and strategy. 

With the right approach, commitment and investment, Africa can rapidly change the fate of its citizens by effectively using space science and technology to support and drive its developmental agenda.