Comparative analysis of glutaredoxin domains from bacterial opportunistic pathogens

NMR structures of the glutaredoxin (GLXR) domains from Br. melitensis and Ba. henselae have been determined as part of the SSGCID initiative. Comparison of the domains with known structures reveals overall structural similarity between these proteins and previously determined E. coli GLXR structures, with minor changes associated with the position of helix 1 and with regions that diverge from similar structures found in the closest related human homolog

Is there a genetic cause for cancer cachexia? - a clinical validation study in 1797 patients

Peer reviewedPublisher PD

Unbound pavement materials' response to varying groundwater table analysed by falling weight deflectometer

Expected climate changes will in many areas represent a shift towards increased precipitation and more intense rainfall events. This may lead to increased moisture within road structures and possible overloading of road drainage systems. Pavement design methods must therefore be able to predict the behaviour of pavement materials at increased moisture levels. An instrumented accelerated pavement test (APT) has been conducted on two thin flexible pavement structures with coarse-grained unbound base course and subbase materials using a heavy vehicle simulator (HVS). The two pavement structures were identical except for the particle size distribution (PSD) of the subbase materials, where one had a dense 0/90 mm curve with a controlled fines content, and the other had an open-graded 22/90 mm curve. The APT was conducted using constant dual wheel loading, and three different ground- water levels were induced in order to change the moisture content in the structures. Falling weight deflectometer (FWD) measurements were conducted at each groundwater level during the APT. Additional FWD measurements were conducted as the groundwater was lowered after the APT loading was finished. The moisture content in the unbound materials was con- tinuously measured throughout the test. The analysis is focussed on the response of the unbound aggregate layers to varying moisture levels in the pavement structures. Analysis results show how the dense- and open-graded materials respond to the moving groundwater table, and how this affects the deflection of the full structures

Biophysical properties of regions flanking the bHLH-Zip motif in the p22 Max protein

The Max protein is the central dimerization partner in the Myc-Max-Mad network of transcriptional regulators, and a founding structural member of the family of basic-helix-loop-helix (bHLH)-leucine zipper (Zip) proteins. Biologically important regions flanking its bHLH-Zip motif have been disordered or absent in crystal structures. The present study shows that these regions are resistant to proteolysis in both the presence and absence of DNA, and that Max dimers containing both flanking regions have significantly higher helix content as measured by circular dichroism than that predicted from the crystal structures. Nuclear magnetic resonance measurements in the absence of DNA also support the inferred structural order. Deletion of both flanking regions is required to achieve maximal DNA affinity as measured by EMSA. Thus, the previously observed functionalities of these Max regions in DNA binding, phosphorylation, and apoptosis are suggested to be linked to structural properties

Molecular Mapping of Functionalities in the Solution Structure of Reduced Grx4, a Monothiol Glutaredoxin from Escherichia coli

The ubiquitous glutaredoxin protein family is present in both prokaryotes and eukaryotes, and is closely related to the thioredoxins, which reduce their substrates using a dithiol mechanism as part of the cellular defense against oxidative stress. Recently identified monothiol glutaredoxins, which must use a different functional mechanism, appear to be essential in both Escherichia coli and yeast and are well conserved in higher order genomes. We have employed high resolution NMR to determine the three-dimensional solution structure of a monothiol glutaredoxin, the reduced E. coli Grx4. The Grx4 structure comprises a glutaredoxin-like alpha-beta fold, founded on a limited set of strictly conserved and structurally critical residues. A tight hydrophobic core, together with a stringent set of secondary structure elements, is thus likely to be present in all monothiol glutaredoxins. A set of exposed and conserved residues form a surface region, implied in glutathione binding from a known structure of E. coli Grx3. The absence of glutaredoxin activity in E. coli Grx4 can be understood based on small but significant differences in the glutathione binding region, and through the lack of a conserved second GSH binding site. MALDI experiments suggest that disulfide formation on glutathionylation is accompanied by significant structural changes, in contrast with dithiol thioredoxins and glutaredoxins, where differences between oxidized and reduced forms are subtle and local. Structural and functional implications are discussed with particular emphasis on identifying common monothiol glutaredoxin properties in substrate specificity and ligand binding events, linking the thioredoxin and glutaredoxin systems

Influence from genetic variability on opioid use for cancer pain: A European genetic association study of 2294 cancer pain patients

Cancer pain patients need variable opioid doses. Preclinical and clinical studies suggest that opioid efficacy is related to genetic variability. However, the studies have small samples, findings are not replicated, and several candidate genes have not been studied. Therefore, a study of genetic variability with opioid doses in a large population using a confirmatory validation population was warranted. We recruited 2294 adult European patients using a World Health Organization (WHO) step III opioid and analyzed single nucleotide polymorphisms (SNPs) in genes with a putative influence on opioid mechanisms. The patients' mean age was 62.5 years, and the average pain intensity was 3.5. The patients' primary opioids were morphine (n = 830), oxycodone (n = 446), fentanyl (n = 699), or other opioids (n = 234). Pain intensity, time on opioids, age, gender, performance status, and bone or CNS metastases predicted opioid dose and were included as covariates. The patients were randomly divided into 1 development sample and 1 validation sample. None of 112 SNPs in the 25 candidate genes OPRM1, OPRD1, OPRK1, ARRB2, GNAZ, HINT1, Stat6, ABCB1, COMT, HRH1, ADRA2A, MC1R, TACR1, GCH1, DRD2, DRD3, HTR3A, HTR3B, HTR2A, HTR3C, HTR3D, HTR3E, HTR1, or CNR1 showed significant associations with opioid dose in both the development and the validation analyzes. These findings do not support the use of pharmacogenetic analyses for the assessed SNPs to guide opioid treatment. The study also demonstrates the importance of validating findings obtained in genetic association studies to avoid reporting spurious associations as valid findings. To elicit knowledge about new genes that influence pain and the need for opioids, strategies other than the candidate gene approach is needed. (C) 2011 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved