Effect of temperature and nucleotide on the binding of BiP chaperone to a protein substrate

BiP (immunoglobulin heavy-chain Binding Protein) is a Hsp70 monomeric ATPase motor that plays broad and crucial roles maintaining proteostasis inside the cell. Structurally, BiP is formed by two domains, a nucleotide-binding domain (NBD) with ATPase activity connected by a flexible hydrophobic linker to the substrate-binding domain (SBD). While the ATPase and substrate binding activities of BiP are allosterically coupled, the latter is also dependent on nucleotide binding. Recent structural studies have provided new insights into BiP's allostery; however, the influence of temperature on the coupling between substrate and nucleotide binding to BiP remains unexplored. Here we study BiP's binding to its substrate at the single molecule level using thermo-regulated optical tweezers which allows us to mechanically unfold the client protein and explore the effect of temperature and different nucleotides on BiP binding. Our results confirm that the affinity of BiP for its protein substrate relies on nucleotide binding, by mainly regulating the binding kinetics between BiP and its substrate. Interestingly, our findings also showed that the apparent affinity of BiP for its protein substrate in the presence of nucleotides remains invariable over a wide range of temperatures, suggesting that BiP may interact with its client proteins with similar affinities even when the temperature is not optimal. Thus, BiP could play a role as a "thermal buffer" in proteostasis. This article is protected by copyright. All rights reserved

Climate adaptation and agriculture: Solutions to successful national adaptation plans

The purpose of this brief is to share insights on agriculture and NAPs with national-level decision makers in developing countries and Least Developed Countries (LDCs), multilateral agencies, UNFCCC negotiators and donors. This brief explores how countries are overcoming the biggest challenges in developing NAPs, outlines examples of successful cross-sector adaptation planning, explores influence and leverage necessary for successful NAP processes, and offers specific recommendations

Search for Gravitational Waves from Primordial Black Hole Binary Coalescences in the Galactic Halo

We use data from the second science run of the LIGO gravitational-wave detectors to search for the gravitational waves from primordial black hole (PBH) binary coalescence with component masses in the range 0.2--$1.0 M_\odot$. The analysis requires a signal to be found in the data from both LIGO observatories, according to a set of coincidence criteria. No inspiral signals were found. Assuming a spherical halo with core radius 5 kpc extending to 50 kpc containing non-spinning black holes with masses in the range 0.2--$1.0 M_\odot$, we place an observational upper limit on the rate of PBH coalescence of 63 per year per Milky Way halo (MWH) with 90% confidence.Comment: 7 pages, 4 figures, to be submitted to Phys. Rev.

Multiple Colonization with S. pneumoniae before and after Introduction of the Seven-Valent Conjugated Pneumococcal Polysaccharide Vaccine

Simultaneous carriage of more than one strain of Streptococcus pneumoniae promotes horizontal gene transfer events and may lead to capsule switch and acquisition of antibiotic resistance. We studied the epidemiology of cocolonization with S. pneumoniae before and after introduction of the seven-valent conjugated pneumococcal vaccine (PCV7)

Global, regional, and national comparative risk assessment of 79 behavioural, environmental and occupational, and metabolic risks or clusters of risks, 1990-2015: a systematic analysis for the Global Burden of Disease Study 2015

SummaryBackground The Global Burden of Diseases, Injuries, and Risk Factors Study 2015 provides an up-to-date synthesis of the evidence for risk factor exposure and the attributable burden of disease. By providing national and subnational assessments spanning the past 25 years, this study can inform debates on the importance of addressing risks in context. Methods We used the comparative risk assessment framework developed for previous iterations of the Global Burden of Disease Study to estimate attributable deaths, disability-adjusted life-years (DALYs), and trends in exposure by age group, sex, year, and geography for 79 behavioural, environmental and occupational, and metabolic risks or clusters of risks from 1990 to 2015. This study included 388 risk-outcome pairs that met World Cancer Research Fund-defined criteria for convincing or probable evidence. We extracted relative risk and exposure estimates from randomised controlled trials, cohorts, pooled cohorts, household surveys, census data, satellite data, and other sources. We used statistical models to pool data, adjust for bias, and incorporate covariates. We developed a metric that allows comparisons of exposure across risk factors—the summary exposure value. Using the counterfactual scenario of theoretical minimum risk level, we estimated the portion of deaths and DALYs that could be attributed to a given risk. We decomposed trends in attributable burden into contributions from population growth, population age structure, risk exposure, and risk-deleted cause-specific DALY rates. We characterised risk exposure in relation to a Socio-demographic Index (SDI). Findings Between 1990 and 2015, global exposure to unsafe sanitation, household air pollution, childhood underweight, childhood stunting, and smoking each decreased by more than 25%. Global exposure for several occupational risks, high body-mass index (BMI), and drug use increased by more than 25% over the same period. All risks jointly evaluated in 2015 accounted for 57·8% (95% CI 56·6–58·8) of global deaths and 41·2% (39·8–42·8) of DALYs. In 2015, the ten largest contributors to global DALYs among Level 3 risks were high systolic blood pressure (211·8 million [192·7 million to 231·1 million] global DALYs), smoking (148·6 million [134·2 million to 163·1 million]), high fasting plasma glucose (143·1 million [125·1 million to 163·5 million]), high BMI (120·1 million [83·8 million to 158·4 million]), childhood undernutrition (113·3 million [103·9 million to 123·4 million]), ambient particulate matter (103·1 million [90·8 million to 115·1 million]), high total cholesterol (88·7 million [74·6 million to 105·7 million]), household air pollution (85·6 million [66·7 million to 106·1 million]), alcohol use (85·0 million [77·2 million to 93·0 million]), and diets high in sodium (83·0 million [49·3 million to 127·5 million]). From 1990 to 2015, attributable DALYs declined for micronutrient deficiencies, childhood undernutrition, unsafe sanitation and water, and household air pollution; reductions in risk-deleted DALY rates rather than reductions in exposure drove these declines. Rising exposure contributed to notable increases in attributable DALYs from high BMI, high fasting plasma glucose, occupational carcinogens, and drug use. Environmental risks and childhood undernutrition declined steadily with SDI; low physical activity, high BMI, and high fasting plasma glucose increased with SDI. In 119 countries, metabolic risks, such as high BMI and fasting plasma glucose, contributed the most attributable DALYs in 2015. Regionally, smoking still ranked among the leading five risk factors for attributable DALYs in 109 countries; childhood underweight and unsafe sex remained primary drivers of early death and disability in much of sub-Saharan Africa. Interpretation Declines in some key environmental risks have contributed to declines in critical infectious diseases. Some risks appear to be invariant to SDI. Increasing risks, including high BMI, high fasting plasma glucose, drug use, and some occupational exposures, contribute to rising burden from some conditions, but also provide opportunities for intervention. Some highly preventable risks, such as smoking, remain major causes of attributable DALYs, even as exposure is declining. Public policy makers need to pay attention to the risks that are increasingly major contributors to global burden. Funding Bill & Melinda Gates Foundation

Dynamics of pneumococcal nasopharyngeal carriage in healthy children attending a day care center in northern Spain. influence of detection techniques on the results

<p>Abstract</p> <p>Background</p> <p>Pneumococcal nasopharyngeal carriage precedes invasive infection and is the source for dissemination of the disease. Differences in sampling methodology, isolation or identification techniques, as well as the period (pre -or post-vaccination) when the study was performed, can influence the reported rates of colonization and the distribution of serotypes carried.</p> <p>Objectives</p> <p>To evaluate the prevalence and dynamics of pneumococcal nasopharyngeal colonization in healthy children aged 6-34 months attending a day care center with a high level of hygiene and no overcrowding. The study was performed 3-4 years after the 7-valent pneumococcal vaccine was introduced, using multiple methodologies to detect and characterize the isolates.</p> <p>Methods</p> <p>Over 12 months, 25 children were sampled three times, 53 children twice and 27 children once. Three <it>Streptococcus pneumoniae </it>typing techniques were used: Quellung, Pneumotest-Latex-kit and multiplex-polymerase chain reaction (PCR). The similarity of isolates of the same serotype was established by pulsed field gel electrophoresis (PFGE) and occasionally the multilocus sequence type (ST) was also determined.</p> <p>Results</p> <p>Overall pneumococcal carriage and multiple colonization rates were 89.5% (94/105) and 39%, respectively. Among 218 pneumococci detected, 21 different serotypes and 13 non-typeable isolates were found. The most prevalent serotypes were 19A, 16F and 15B. Serotypes 15B, 19A and 21 were mainly found as single carriage; in contrast serotypes 6B, 11A and 20, as well as infrequent serotypes, were isolated mainly as part of multiple carriage. Most 19A isolates were ST193 but most serotypes showed high genetic heterogeneity. Changes in the pneumococci colonizing each child were frequent and the same serotype detected on two occasions frequently showed a different genotype. By multiplex-PCR, 100% of pneumococci could be detected and 94% could be serotyped versus 80.3% by the Quellung reaction and Pneumotest-Latex in combination (p < 0.001).</p> <p>Conclusions</p> <p>Rates of <it>S. pneumoniae </it>carriage and multiple colonization were very high. Prevalent serotypes differed from those found in similar studies in the pre-vaccination period. In the same child, clearance of a pneumococcal strain and acquisition of a new one was frequent in a short period of time. The most effective technique for detecting pneumococcal nasopharyngeal carriers was multiplex-PCR.</p

Performance of the CMS Cathode Strip Chambers with Cosmic Rays

The Cathode Strip Chambers (CSCs) constitute the primary muon tracking device in the CMS endcaps. Their performance has been evaluated using data taken during a cosmic ray run in fall 2008. Measured noise levels are low, with the number of noisy channels well below 1%. Coordinate resolution was measured for all types of chambers, and fall in the range 47 microns to 243 microns. The efficiencies for local charged track triggers, for hit and for segments reconstruction were measured, and are above 99%. The timing resolution per layer is approximately 5 ns

Antigenic Fingerprinting of H5N1 Avian Influenza Using Convalescent Sera and Monoclonal Antibodies Reveals Potential Vaccine and Diagnostic Targets

Using whole-genome-fragment phage display libraries, Hana Golding and colleagues identify the viral epitopes recognized by serum antibodies in humans who have recovered from infection with H5N1 avian influenza

Decrease in Pneumococcal Co-Colonization following Vaccination with the Seven-Valent Pneumococcal Conjugate Vaccine

Understanding the epidemiology of pneumococcal co-colonization is important for monitoring vaccine effectiveness and the occurrence of horizontal gene transfer between pneumococcal strains. In this study we aimed to evaluate the impact of the seven-valent pneumococcal conjugate vaccine (PCV7) on pneumococcal co-colonization among Portuguese children. Nasopharyngeal samples from children up to 6 years old yielding a pneumococcal culture were clustered into three groups: pre-vaccine era (n = 173), unvaccinated children of the vaccine era (n = 169), and fully vaccinated children (4 doses; n = 150). Co-colonization, serotype identification, and relative serotype abundance were detected by analysis of DNA of the total bacterial growth of the primary culture plate using the plyNCR-RFLP method and a molecular serotyping microarray-based strategy. The plyNCR-RFLP method detected an overall co-colonization rate of 20.1%. Microarray analysis confirmed the plyNCR-RFLP results. Vaccination status was the only factor found to be significantly associated with co-colonization: co-colonization rates were significantly lower (p = 0.004; Fisher's exact test) among fully vaccinated children (8.0%) than among children from the pre-PCV7 era (17.3%) or unvaccinated children of the PCV7 era (18.3%). In the PCV7 era there were significantly less non-vaccine type (NVT) co-colonization events than would be expected based on the NVT distribution observed in the pre-PCV7 era (p = 0.024). In conclusion, vaccination with PCV7 resulted in a lower co-colonization rate due to an asymmetric distribution between NVTs found in single and co-colonized samples. We propose that some NVTs prevalent in the PCV7 era are more competitive than others, hampering their co-existence in the same niche. This result may have important implications since a decrease in co-colonization events is expected to translate in decreased opportunities for horizontal gene transfer, hindering pneumococcal evolution events such as acquisition of antibiotic resistance determinants or capsular switch. This might represent a novel potential benefit of conjugate vaccines