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Speaking at a function in Varanasi on the occasion of Ravidas Jayanti, she urged the audience to take the teachings of the saint to the masses. "He (Sant Ravidas) had dreamt of a society, where there is no discrimination and where every person is respected. You all should take forward his teachings to the masses, especially at a time, when there is so much violence and hatred in the society. His teachings are need of the hour," Priyanka Gandhi said.

Gymnastics: Italian Lodadio cultivates his garden to stay fit

The structure and function of dioxygenases in histone demethylation and DNA/RNA dimethylation are discussed.

Gluconate 5-dehydrogenase (Ga5DH; EC 1.1.1.69) from Lentibacter algarum (LaGa5DH) was recombinantly expressed in Escherichia coli and purified to homogeneity. The protein was crystallized and the crystal structure was solved at 2.1 Å resolution. The crystal belonged to the monoclinic system, with space group P1 and unit-cell parameters a = 55.42, b = 55.48, c = 79.16 Å, α = 100.51, β = 105.66, γ = 97.99°. The structure revealed LaGaDH to be a tetramer, with each subunit consisting of six α-helices and three antiparallel β-hairpins. LaGa5DH has high structural similarity to other Ga5DH proteins, demonstrating that this enzyme is highly conserved.

The bacterial type VI secretion system (T6SS) secretes many toxic effectors to gain advantage in interbacterial competition and for eukaryotic host infection. The cognate immunity proteins of these effectors protect bacteria from their own effectors. PldB is a T6SS trans-kingdom effector in Pseudomonas aeruginosa that can infect both prokaryotic and eukaryotic cells. Three proteins, PA5086, PA5087 and PA5088, are employed to suppress the toxicity of PldB-family proteins. The structures of PA5087 and PA5088 have previously been reported, but the identification of further distinctions between these immunity proteins is needed. Here, the crystal structure of PA5086 is reported at 1.90 Å resolution. A structural comparison of the three PldB immunity proteins showed vast divergences in their electrostatic potential surfaces. This interesting phenomenon provides an explanation of the stockpiling mechanism of T6SS immunity proteins.

Factor for inversion stimulation (Fis) is a versatile bacterial nucleoid-associated protein that can directly bind and bend DNA to influence DNA topology. It also plays crucial roles in regulating bacterial virulence factors and in optimizing bacterial adaptation to various environments. Fis from Pseudomonas aeruginosa (PA4853, referred to as PaFis) has recently been found to be required for virulence by regulating the expression of type III secretion system (T3SS) genes. PaFis can specifically bind to the promoter region of exsA, which functions as a T3SS master regulator, to regulate its expression and plays an essential role in transcription elongation from exsB to exsA. Here, the crystal structure of PaFis, which is composed of a four-helix bundle and forms a homodimer, is reported. PaFis shows remarkable structural similarities to the well studied Escherichia coli Fis (EcFis), including an N-terminal flexible loop and a C-terminal helix–turn–helix (HTH) motif. However, the critical residues for Hin-catalyzed DNA inversion in the N-terminal loop of EcFis are not conserved in PaFis and further studies are required to investigate its exact role. A gel-electrophoresis mobility-shift assay showed that PaFis can efficiently bind to the promoter region of exsA. Structure-based mutagenesis revealed that several conserved basic residues in the HTH motif play essential roles in DNA binding. These structural and biochemical studies may help in understanding the role of PaFis in the regulation of T3SS expression and in virulence.

Death-associated protein kinase 1 (DAPK1) was found to form a complex with purpurin and the crystal structure of the complex was determined. Purpurin may be a good lead compound for for the discovery of inhibitors of DAPK1.

A new form of NaMnAsO4, sodium manganese(II) orthoarsenate, has been obtained under hydro­thermal conditions, and is referred to as the β-polymorph. In contrast to the previously reported ortho­rhom­bic α-polymorph that crystallizes in the olivine-type of structure and has one manganese(II) cation in a distorted octa­hedral coordination, the current β-polymorph contains two manganese(II) cations in [5]-coordination, inter­mediate between a square-pyramid and a trigonal bipyramid. In the crystal structure of β-NaMnAsO4, four [MnO5] polyhedra are linked through vertex- and edge-sharing into finite {Mn4O16} units strung into rows parallel to [100]. These units are linked through two distinct orthoarsenate groups into a framework structure with channels propagating parallel to the manganese oxide rows. Both unique sodium cations are situated inside the channels and exhibit coordination numbers of six and seven. β-NaMnAsO4 is isotypic with one form of NaCoPO4 and with NaCuAsO4.

MICAL is an oxidoreductase that participates in cytoskeleton reorganization via actin disassembly in the presence of NADPH. Although three MICALs (MICAL1, MICAL2 and MICAL3) have been identified in mammals, only the structure of mouse MICAL1 has been reported. Here, the first crystal structure of human MICAL3, which contains the flavin-containing monooxygenase (FMO) and calponin-homology (CH) domains, is reported. MICAL3 has an FAD/NADP-binding Rossmann-fold domain for mono­oxygenase activity like MICAL1. The FMO and CH domains of both MICAL3 and MICAL1 are highly similar in structure, but superimposition of the two structures shows a different relative position of the CH domain in the asymmetric unit. Based on kinetic analyses, the catalytic efficiency of MICAL3 dramatically increased on adding F-actin only when the CH domain was available. However, this did not occur when two residues, Glu213 and Arg530, were mutated in the FMO and CH domains, respectively. Overall, MICAL3 is structurally highly similar to MICAL1, which suggests that they may adopt the same catalytic mechanism, but the difference in the relative position of the CH domain produces a difference in F-actin substrate specificity.

Malaria is a devastating disease caused by a protozoan parasite. It affects over 300 million individuals and results in over 400 000 deaths annually, most of whom are young children under the age of five. Hexokinase, the first enzyme in glucose metabolism, plays an important role in the infection process and represents a promising target for therapeutic intervention. Here, cryo-EM structures of two conformational states of Plasmodium vivax hexokinase (PvHK) are reported at resolutions of ∼3 Å. It is shown that unlike other known hexokinase structures, PvHK displays a unique tetrameric organization (∼220 kDa) that can exist in either open or closed quaternary conformational states. Despite the resemblance of the active site of PvHK to its mammalian counterparts, this tetrameric organization is distinct from that of human hexokinases, providing a foundation for the structure-guided design of parasite-selective antimalarial drugs.

The bacterial flavin adenine dinucleotide (FAD)-dependent glucose dehydrogenase complex derived from Burkholderia cepacia (BcGDH) is a representative molecule of direct electron transfer-type FAD-dependent dehydrogenase complexes. In this study, the X-ray structure of BcGDHγα, the catalytic subunit (α-subunit) of BcGDH complexed with a hitchhiker protein (γ-subunit), was determined. The most prominent feature of this enzyme is the presence of the 3Fe–4S cluster, which is located at the surface of the catalytic subunit and functions in intramolecular and intermolecular electron transfer from FAD to the electron-transfer subunit. The structure of the complex revealed that these two molecules are connected through disulfide bonds and hydrophobic interactions, and that the formation of disulfide bonds is required to stabilize the catalytic subunit. The structure of the complex revealed the putative position of the electron-transfer subunit. A comparison of the structures of BcGDHγα and membrane-bound fumarate reductases suggested that the whole BcGDH complex, which also includes the membrane-bound β-subunit containing three heme c moieties, may form a similar overall structure to fumarate reductases, thus accomplishing effective electron transfer.

The crystal structure of gluconate 5-dehydrogenase from Lentibacter algarum is reported. It has high structural similarity to other gluconate 5-dehydrogenase proteins, demonstrating that this enzyme is highly conserved.

The crystal structure of Pseudomonas aeruginosa Fis is composed of an N-terminal flexible loop and a C-terminal helix–turn–helix motif.

The structure of the Pseudomonas aeruginosa T6SS PldB immunity protein PA5086 is reported at 1.9 Å resolution. Comparison of PA5086 with its homologs PA5087 and PA5088 showed great similarities in sequence and structure, but vast divergences in electrostatic potential surfaces.

The Smithsonian Astrophysical Observatory is a major partner in the Atmospheric Imaging Assembly, which is a group of four telescopes on NASA's Solar Dynamics Observatory that photograph the sun in 10 different wavelength bands, or colors, once every 10 seconds.

The post NASA’s new eye on the sun delivers stunning images appeared first on Smithsonian Insider.

On the Smithsonian Tropical Research Institute's Barro Colorado Island in the Panama Canal, staff members are taking down a network of seven tall Automated Radio Telemetry System towers used to track animals wearing radio-transmitters. Scientists on the island are switching to GPS and camera trap systems to produce more data with less infrastructure.

The post GPS and camera traps to replace radio antennas in tracking animals on Barro Colorado Island appeared first on Smithsonian Insider.

The National Aeronautics and Space Administration has made available to the public a new online collection of images that capture the excitement of planetary exploration and the journey to understand the origin and evolution of the solar system.

The post Stunning high-resolution NASA images available online for public exhibits appeared first on Smithsonian Insider.

The Smithsonian Astrophysical Observatory has been awarded a NASA project to build the Tropospheric Emissions: Monitoring of Pollution (TEMPO) instrument. TEMPO will measure North American air pollution, from Mexico City to the Canadian tar/oil sands, and from the Atlantic to the Pacific, hourly and at high spatial resolution.

The post NASA funds Smithsonian Astrophysical Observatory instrument to track North American air pollution appeared first on Smithsonian Insider.

NASA's next Small Explorer (SMEX) mission to study the little-understood lower levels of the sun's atmosphere has been fully integrated and final testing is underway.

The post NASA’s IRIS spacecraft scheduled to launch in April appeared first on Smithsonian Insider.

NASA’s Interface Region Imaging Spectrograph (IRIS) spacecraft launched at 10:27 p.m. EDT Wednesday, June 26 from Vandenberg Air Force Base, Calif. Its primary goal is […]

The post NASA launches IRIS carrying Smithsonian-built telescope appeared first on Smithsonian Insider.

For the first time since exoplanets, or planets around stars other than the sun, were discovered almost 20 years ago, X-ray observations have detected an […]

The post NASA’s Chandra sees eclipsing planet in X-rays for first time appeared first on Smithsonian Insider.

Tiny and transparent the marine crustacean Paraphronima gracilis sees the world through two large eyes that envelope its head like a high-tech space helmet. Now, […]

The post Bizarre ocean amphipod has 16 retinas in each eye appeared first on Smithsonian Insider.

NASA’s InSight probe, scheduled to land on the surface of Mars in November 2018, will be boring. Boring a hole, that is. It will drill […]

The post ISO: a boring Martian landing spot for NASA’s InSight probe appeared first on Smithsonian Insider.

Pullulanase (EC 3.2.1.41) is a well known starch-debranching enzyme that catalyzes the cleavage of α-1,6-glycosidic linkages in α-glucans such as starch and pullulan. Crystal structures of a type I pullulanase from Paenibacillus barengoltzii (PbPulA) and of PbPulA in complex with maltopentaose (G5), maltohexaose (G6)/α-cyclodextrin (α-CD) and β-cyclodextrin (β-CD) were determined in order to better understand substrate binding to this enzyme. PbPulA belongs to glycoside hydrolase (GH) family 13 subfamily 14 and is composed of three domains (CBM48, A and C). Three carbohydrate-binding sites identified in PbPulA were located in CBM48, near the active site and in domain C, respectively. The binding site in CBM48 was specific for β-CD, while that in domain C has not been reported for other pullulanases. The domain C binding site had higher affinity for α-CD than for G6; a small motif (FGGEH) seemed to be one of the major determinants for carbohydrate binding in this domain. Structure-based mutations of several surface-exposed aromatic residues in CBM48 and domain C had a debilitating effect on the activity of the enzyme. These results suggest that both CBM48 and domain C play a role in binding substrates. The crystal forms described contribute to the understanding of pullulanase domain–carbohydrate interactions.

Death-associated protein kinase 1 (DAPK1) is a serine/threonine protein kinase that regulates apoptosis and autophagy. DAPK1 is considered to be a therapeutic target for amyloid-β deposition, endometrial adenocarcinomas and acute ischemic stroke. Here, the potent inhibitory activity of the natural anthraquinone purpurin against DAPK1 phosphorylation is shown. Thermodynamic analysis revealed that while the binding affinity of purpurin is similar to that of CPR005231, which is a DAPK1 inhibitor with an imidazopyridazine moiety, the binding of purpurin was more enthalpically favorable. In addition, the inhibition potencies were correlated with the enthalpic changes but not with the binding affinities. Crystallographic analysis of the DAPK1–purpurin complex revealed that the formation of a hydrogen-bond network is likely to contribute to the favorable enthalpic changes and that stabilization of the glycine-rich loop may cause less favorable entropic changes. The present findings indicate that purpurin may be a good lead compound for the discovery of inhibitors of DAPK1, and the observation of enthalpic changes could provide important clues for drug development.

During a press conference Friday, July 22 at the Smithsonian's National Air and Space Museum, NASA announced that Gale Crater will be the landing site for the Mars Science Laboratory. Scheduled to launch in late 2011 and arrive at Mars in August 2012, the Mars Science Laboratory is a rover that will assess the planet’s “habitability”—if it ever was, or is today, an environment able to support microbial life.

The post Gale Crater to be landing site for NASA’s Mars Science Laboratory appeared first on Smithsonian Insider.

NASA, the National Science Foundation and the Smithsonian recently renewed their agreement to search for, collect and curate Antarctic meteorites in a partnership known as […]

The post NASA, Smithsonian renew hunt for Antarctic meteorites appeared first on Smithsonian Insider.

This new PBS Newshour video takes a look at a new exhibit at the Air and Space Museum celebrating NASA's space art program.

The post PBS Newshour takes a look at the new National Air and Space Museum exhibition “NASA | ART: 50 Years of Exploration” appeared first on Smithsonian Insider.

The National Air and Space Museum’s 2014 Trophy Award Winner for Current Achievement goes to the Dawn Flight Team. The Dawn team has successfully performed […]

The post The Dawn Flight Team – 2014 NASM Trophy Winner appeared first on Smithsonian Insider.

NASA’s Kepler mission is responsible for history’s first detection of Earth-sized planets orbiting other suns in their temperate “habitable zones.” The team in charge of […]

The post NASA’s Kepler mission receives National Air and Space Museum’s highest group honor appeared first on Smithsonian Insider.

Candy Feller, senior ecologist at the Smithsonian Environmental Research Center in Edgewater, Md., will lead an effort to track more than 100 miles of Florida mangrove forests that are encroaching on salt marshes to the north.

The post NASA to help Smithsonian botanists track northern creep of Florida mangroves appeared first on Smithsonian Insider.

The Council of the National Academy of Sciences (NAS) is concerned about the confusion caused by a petition being circulated via a letter from a former president of this Academy.

Marijuanas active components are potentially effective in treating pain, nausea, the anorexia of AIDS wasting, and other symptoms, and should be tested rigorously in clinical trials.

Today President Obama signed a Presidential Memorandum to address climate change and national security. The National Academies of Sciences, Engineering, and Medicine look forward to taking the lead in engaging the academic community in efforts to guide this initiative, and are well-positioned to tap the broad, multidisciplinary expertise of researchers across the nation.

Today during the National Academy of Sciences 154th annual meeting, in her first speech to the members of the Academy, NAS President Marcia McNutt stressed the ongoing vitality of America’s scientific enterprise, and called on the country to strengthen its support for science and to continue to turn to science for solutions to the nation’s and the world’s most pressing challenges.

NASA’s large strategic missions like the Hubble Space Telescope, the Curiosity rover on Mars, and the Terra Earth observation satellite are essential to maintaining the United States’ global leadership in space exploration and should continue to be a primary component of a balanced space science program that includes large, medium, and smaller missions, says a new report by the National Academies of Sciences, Engineering, and Medicine.

Although NASA has made progress toward the overall space exploration science priorities recommended in a 2011 decadal survey by the National Academies of Sciences, Engineering, and Medicine, the space agency should raise the priority of scientific research that addresses the risks and unknowns of human space exploration.

We are concerned deeply by a report that staff at the Centers for Disease Control and Prevention were instructed not to use certain words in budget documents. As leaders of the National Academies of Sciences, Engineering, and Medicine, we are especially stunned that “evidence-based” and “science-based” are reportedly among the barred terms.

The highest standards of scientific integrity, transparency, and accountability are critical to maintaining public confidence in our nation’s research enterprise and in the wise use of the public investment in research.

We are pleased to announce that the National Academies of Sciences, Engineering, and Medicine are exploring ways to mobilize our expertise to counter misinformation on the web related to science, engineering, and health.

NAS President Marcia McNutt, NAE President C. D. Mote, Jr., and NAM President Victor J. Dzau honored U.S. 2017 Nobel Prize recipients Barry Barish, Joachim Frank, Michael Rosbash, Kip Thorne, and Michael Young at a reception on Capitol Hill on Wednesday, April 18. U.S. Senators Lamar Alexander (R-Tenn.) and Christopher Coons (D-Del.) co-hosted the event.

From April 28 to May 1 the National Academy of Sciences will hold its 155th annual meeting.

During a ceremony at its 155th annual meeting, the National Academy of Sciences presented the 2018 Public Welfare Medal to physician, anthropologist, and humanitarian Paul Farmer.

The current process for planetary protection policy development is inadequate to respond to increasingly complex solar system exploration missions, says a new report from the National Academies of Sciences, Engineering, and Medicine.

I am pleased that the White House is moving to fill the position of director of the Office of Science and Technology Policy.