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Erythromycin-resistance methyltransferases are SAM dependent Rossmann fold methyltransferases that convert A2058 of 23S rRNA to m6 2A2058. This modification sterically blocks binding of several classes of antibiotics to 23S rRNA, resulting in a multidrug-resistant phenotype in bacteria expressing the enzyme. ErmC is an erythromycin resistance methyltransferase found in many Gram-positive pathogens, whereas ErmE is found in the soil bacterium that biosynthesizes erythromycin. Whether ErmC and ErmE, which possess only 24% sequence identity, use similar structural elements for rRNA substrate recognition and positioning is not known. To investigate this question, we used structural data from related proteins to guide site-saturation mutagenesis of key residues and characterized selected variants by antibiotic susceptibility testing, single turnover kinetics, and RNA affinity–binding assays. We demonstrate that residues in α4, α5, and the α5-α6 linker are essential for methyltransferase function, including an aromatic residue on α4 that likely forms stacking interactions with the substrate adenosine and basic residues in α5 and the α5-α6 linker that likely mediate conformational rearrangements in the protein and cognate rRNA upon interaction. The functional studies led us to a new structural model for the ErmC or ErmE-rRNA complex.

UK-based, Jamaica-born dancehall artiste Dubbi believes latest single, ' Side Chick' is a bona fide hit as its popularity has surged on the dancehall scene in the United Kingdom. "It is also streaming well in France and seems to be a real hit on...

After parking his taxi cab along the sidewalk, Leon Thompson exited his vehicle and held on tightly to the tiny hands of his four small passengers. They all walked towards a makeshift bridge, and Thompson lifted each child, making four trips,...

In a touching display of compassion and solidarity, a group of St Thomas residents has come together to organise the funeral of a a well-known and beloved man with intellectual challenges. For years, Donovan Sinclair was a familiar face in the...

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.

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What challenges does the new president of Somalia face? Explainer Video aboudiaf.drupal 28 June 2022

Ahmed Soliman examines the challenges the new president Hassan Sheikh Mohamud faces in his first 100 days as president.

Key issues for the new administration are a deteriorating situation with regards to drought as close to half the population are facing food insecurity due to a fourth failed rainy season.

Combined with an inflation rate above ten per cent, many Somalis are at risk of famine and starvation. Many areas of the country are affected from the pastoralist regions to those which house IDP camps around the capital city and other towns, all being exacerbated by the war in Ukraine as Somalia was importing much of its wheat imports from Ukraine and Russia.

Sophos X-Ops unveils five-year investigation tracking China-based groups targeting perimeter devices

Daphne E.C. Boer
Dec 23, 2020; 0:jlr.RA120001043v1-jlr.RA120001043
Research Articles

Douglas A. Andres
Dec 1, 2020; 61:1537-1537
Images in Lipid Research

Deficiency of glucocerebrosidase (GBA), a lysosomal β-glucosidase, causes Gaucher disease. The enzyme hydrolyzes β-glucosidic substrates and transglucosylates cholesterol to cholesterol-β-glucoside. Here we show that recombinant human GBA also cleaves β-xylosides and transxylosylates cholesterol. The xylosyl-cholesterol formed acts as acceptor for subsequent formation of di-xylosyl-cholesterol. Common mutant forms of GBA from patients with Gaucher disease with reduced β-glucosidase activity were similarly impaired in β-xylosidase, transglucosidase and transxylosidase activities, except for a slightly reduced xylosidase/glucosidase activity ratio of N370S GBA and a slightly reduced transglucosylation/glucosidase activity ratio of D409H GBA. XylChol was found to be reduced in spleen from Gaucher disease patients. The origin of newly identified XylChol in mouse and human tissues was investigated. Cultured human cells exposed to exogenous β-xylosides generated XylChol in a manner dependent on active lysosomal GBA but not the cytosol-facing β-glucosidase GBA2. We later sought an endogenous β-xyloside acting as donor in transxylosylation reactions, identifying xylosylated ceramide (XylCer) in cells and tissues that serve as donor in the formation of XylChol. UDP-glucosylceramide synthase (GCS) was unable to synthesize XylChol but could catalyse formation of XylCer. Thus, food-derived β-D-xyloside and XylCer are potential donors for the GBA-mediated formation of XylChol in cells. The enzyme GCS produces XylCer at a low rate. Our findings point to further catalytic versatility of GBA and prompt a systematic exploration of the distribution and role of xylosylated lipids.

Proportionality in the Conduct of Hostilities: The Incidental Harm Side of the Assessment Research paper sysadmin 6 December 2018

Clarification of international humanitarian law is important in ensuring compliance with the rule of proportionality, but a culture of compliance within armed forces and groups is also crucial.

Summary

• Military operations are taking place with increasing frequency in densely populated areas. Such operations result in loss of life and harm to civilians, as well as damage to civilian objects, (including infrastructure providing essential services). In order to protect civilians, it is imperative that armed forces and groups comply with the rules of international humanitarian law on the conduct of hostilities, including the rule of proportionality.
• The rule of proportionality prohibits attacks which may be expected to cause incidental loss of civilian life, injury to civilians, damage to civilian objects or a combination thereof, which would be excessive in relation to the concrete and direct military advantage anticipated. This research paper analyses the key steps that belligerents must take to give effect to the rule, with a particular focus on one side of proportionality assessments – the expected incidental harm.
• Those undertaking proportionality assessments before or during an attack must consider whether the expected harm will be caused by the attack, and whether that harm could be expected (that is, was it reasonably foreseeable).
• For the purpose of proportionality assessments, injury to civilians includes disease, and there is no reason in principle to exclude mental harm, even though it is currently challenging to identify and quantify it. Damage to civilian objects includes damage to elements of the natural environment.
• Once the incidental harm to be considered has been identified, a value or weight must be assigned to it. This is then balanced against the value or weight of the military advantage anticipated from the attack to determine whether the harm would be excessive.
• In the determination of whether the expected incidental harm would be excessive compared to the anticipated military advantage, ‘excessive’ is a wide but not indeterminate standard.
• Belligerents should develop methodologies so that those planning and deciding attacks are provided with all necessary information on expected incidental harm, and to assist them in assigning weight to the incidental harm to be considered.
• If it becomes apparent that the rule of proportionality will be contravened, the attack in question must be cancelled or suspended.
• Clarification of the law is important in ensuring compliance with the rule of proportionality, but a culture of compliance within armed forces and groups, inculcated by their leaders, is also crucial.

Subsidies and Sustainable Agriculture: Mapping the Policy Landscape Research paper sysadmin 10 December 2019

Agricultural subsidies shape production and consumption patterns, with potentially significant effects on poverty, nutrition and other sustainability concerns. This paper maps the different types of support provided by governments to the agricultural sector, and highlights some of the complex political economy dynamics that underpin the relevant policies.

Summary

• Agricultural subsidies, a mainstay of government policy, have a large part in shaping production and consumption patterns, with potentially significant effects as regards poverty, food security, nutrition, and other sustainability concerns such as climate change, land use practices and biodiversity.
• There are multiple types of direct and indirect support provided by governments to various actors in the agricultural sector; and in terms of political economy, there are complex dynamics underpinning the policies that sustain these subsidies.
• Overall, subsidies targeting producers have the most significant effect on production, and the greater trade-distorting effect. These subsidies promote domestic production and discourage imports, leading to overproduction that is largely disposed of on the international market, with the help of export subsidies. This can tend to intensify negative environmental agricultural practices, such as cultivating marginal land, unsustainable types of intensification, or incentivizing excessive pesticide and fertilizer use.
• On the other hand, producer subsidies that are not tied to output of a specific commodity (i.e. delinked) have far fewer distorting impacts and could help to deliver sustainable outcomes. For example, this type of subsidies can require crop diversification or be linked to conservation of permanent grassland.
• Subsidies that enable transfers to consumers, for example through food stamp programmes, also serve to delink production from consumption, can foster healthier diets, can play an important role in delivering food accessibility and security among low-income groups, and can represent one of the less trade-distorting subsidies.
• If subsidies are to be reformed to help promote healthier diets and encourage more sustainable production, it is essential to understand not only the type and amount of support that key countries provide, but also the domestic dynamics that can shape such policies.
• While price support, input subsidies or investment aids remain the central pillars of programmes in large developing countries such as Brazil, China or India, other economies – notably including the EU and Japan – focus on direct payments, support for general services and set-aside schemes, as well as significant border protection. The US, for its part, has tended to focus on subsidized insurance schemes and food programmes for poorer consumers.
• If subsidies are to deliver policy objectives, their design and implementation should delink production from consumption. For example, consumer subsidies designed to deliver nutrition and food security, or payments for environmental services to enable more environmentally friendly production systems, could prove to be the most effective, least trade-distorting means of achieving more sustainable and equitable agricultural production.
• The political economy of food means that the removal of subsidies is often highly sensitive, and tends to be met with significant resistance. However, reform that delinks support from production through a gradual transition process could ultimately prove successful in delivering effective subsidy schemes.
• Effective subsidy schemes must by design be truly result- and performance-based, supported by robust and objective indicators. At the same time, engaging multiple actors along key commodity value chains – including leading importing and exporting countries, traders and transporters – could lead to the development of international, commodity-specific arrangements that are able to deliver effective nutrition and sustainability goals.

Will Rhys Hoskins be bummed if Bryce Harper signs elsewhere?

Chatham House Primer: Inside China’s government 30 November 2022 — 6:00PM TO 6:45PM Anonymous (not verified) 4 October 2022 Chatham House

How are decisions made in Beijing, across China and where does the CCP fit in?

Still little is known in Western circles about the inner workings of China’s government. In power since 1949, the ruling Chinese Communist Party has evolved over decades to its current embodiment under President Xi Jinping.

The need for a better understanding of China’s government has been heightened, particularly as the country navigates post-COVID troubles, global economic downturns, wars in Europe, climate change and heightened tension with the United States.

This Primer has been prepared to pull back the veil on the Chinese government. Key issues to be tackled include:

• What is the decision-making process in China’s government?

• How is the party–government relationship best explained?

• How has the party evolved in recent years with new forms of governance and leadership?

• How has China’s government evolved in recent years, particularly in a globalized environment?

• A description of the central government–province dynamic?

• How are citizens engaged in the political process?

• What are the major centres of power in the Chinese political system?

• Has the COVID-19 pandemic altered attitudes towards and the operation of government?

As with all Chatham House member events, questions from members drive the conversation.

The road to COP27: In conversation with US Special Presidential Envoy for Climate John Kerry 27 October 2022 — 3:00PM TO 4:00PM Anonymous (not verified) 20 October 2022 Chatham House and Online

What will progress on climate change look like at COP27?

With global attention zeroing in on COP27, policymakers and world leaders will meet in Egypt to take the next step in the fight against the climate crisis. The planet is on course to warm well beyond 1.5°C and climate hazards are increasing our exposure to climate risk. Violent and unpredictable weather events increasingly leave devastation among communities, particularly in vulnerable countries.

At the same time, the ripple effects of the conflict in Ukraine will have wide-ranging economic, social and geopolitical consequences for years to come. Whilst some finance is being made available, more is needed to properly address the damage caused by climate change and fund the transition to net zero worldwide. These challenges have become more acute as the world grapples with a growing energy crisis, the war in Ukraine and a troubling economic outlook.

Joined by US Special Presidential Envoy for Climate John Kerry, the following questions are considered:

• Is ‘1.5 degrees’ still on track?

• How can countries better collaborate to move to net zero faster?

• How can we achieve progress on adaptation, climate finance, and loss and damage?

As with all members events, questions from the audience drive the conversation.

Read the transcript. 

President Maia Sandu on democracy and politics in Moldova Video jon.wallace 4 July 2022

The president covers Moldova’s challenges as it seeks closer integration with the European Union.

President Maia Sandu discusses challenges to Moldovan democracy and society during an interview at Chatham House’s 2022 London Conference.

She covers issues including corruption, the presence of Russian troops in the Transnistria region, neutrality in Moldova’s constitution, popular support for EU membership and refugees from Russian aggression in Ukraine.

Officials in Mexico and across Latin America are anxiously watching the outcome of Tuesday's U.S. Presidential contest in light of GOP candidate Donald Trump's campaign promise to "deport 11 million criminal aliens."

The Dow Jones Industrial Average and the S&P 500 hit new highs in early trading on Wednesday as former President Donald Trump claimed victory in Tuesday's presidential election over Kamala Harris.

Unpleasant emotions like sadness and anger can feel overwhelming, but recent research suggests they can trigger behaviors that lead to something better

March 26, 2024 — Scientists at the Department of Energy’s Oak Ridge National Laboratory have determined how to avoid costly and potentially irreparable damage to large metallic parts fabricated through […]

The post ORNL Develops Solution to Residual Stress Challenges in 3D-Printed Metal Structures appeared first on HPCwire.

President Joe Biden will hold a White House meeting with President Prabowo Subianto of Indonesia on Tuesday to celebrate 75 years of U.S.-Indonesian relations and discuss ways to strengthen their countries' cooperation.

Actor Anne Hathaway turns 42 and actor Raffey Cassidy turns 23, among the famous birthdays for Nov. 12.

A New York Supreme Court justice will decide Tuesday if President-elect Donald Trump's sentencing will move forward later this month.

President Joe Biden and Israeli President Isaac Herzog met at the White House on Tuesday afternoon to discuss the war against Hamas and Hezbollah and other Middle East concerns.

President-elect Donald Trump on Monday announced plans to nominate South Dakota Gov. Kristi Noem to head the Department of Homeland Security of his incoming administration.

President-elect Donald Trump on Tuesday night announced his nomination of Fox News host and Army veteran Pete Hegseth to head the Department of Defense.

AI is shaping every aspect of our lives — but only a handful of tech giants have a say in what this technology can do. So what's going on with world governments? Bilawal Sidhu, host of "The TED AI Show," sits down with geopolitical expert Ian Bremmer to unpack the UN's just-released plan for "Governing AI for Humanity," a report that focuses on the urgent need to guide AI towards helping everyone thrive, rather than just the powerful few. Together, they explore the complexities of AI's rapid growth on a worldwide scale and take a clear-eyed look at the pivotal decisions facing us in the very near future.

The U.S. Supreme Court agreed to review a decision by Montana's highest court that struck down a tuition tax-credit program allowing tuition scholarships to benefit students at private religious schools.

The new U.S. Department of Education guidance creates a federal process for individuals and organizations to file complaints under the federal Religious Freedom Restoration Act.

Oregon is the latest state to consider adding an ethnic studies curriculum.

A businessman, Patrick served two terms as governor of Massachusetts and has credited education with his own dramatic rise to success.

After a couple years of clashes with teachers in the state, West Virginia Senate President Mitch Carmichael was ousted in Tuesday's Republican primary election by a teacher.

North Carolina officials' switch in reading-test vendors just weeks before the new school year got underway is spotlighting the often murky process of contracts and procurements for K-12 services.

An Education Week analysis found that at least 140 schools, almost all below the Mason-Dixon line, still bear the names of figures from that era.