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Agathe Anthierens, Nicolas Olivier, Patrick Mucci, André Thevenon
OBJECTIVE: Low back pain is a pathology associated to a trunk extensors muscles weakness. Studies suggested that it could be associated with an inadequacy between oxygen demand and oxygen utilization by paraspinal muscles (Kell and Bhambhani, 2006). In contrast to chronic low back pain (CLBP) patients, judo athletes are characterized by a great trunk extensors muscles endurance, due to their intensive solicitation within sport practice. Our purpose was to compare aerobic metabolism in those muscles of CLBP patients with judo athletes...
September 2016: Annals of Physical and Rehabilitation Medicine
Eva Kummer, Anna Szlachcic, Kamila B Franke, Sophia Ungelenk, Bernd Bukau, Axel Mogk
Escherichia coli ClpB and Saccharomyces cerevisiae Hsp104 are members of the Hsp100 family of ring-forming hexameric AAA+ chaperones that promote the solubilization of aggregated proteins and the propagation of prions. ClpB and Hsp104 cooperate with cognate Hsp70 chaperones for substrate targeting and activation of ATPase and substrate threading, achieved by transient Hsp70 binding to the repressing ClpB/Hsp104 M-domain. Fundamental differences in ATPase regulation and disaggregation mechanisms have been reported; however, these differences are raising doubts regarding the working principle of this AAA+ chaperone...
October 23, 2016: Journal of Molecular Biology
Senthilkumar K Muthusamy, Monika Dalal, Viswanathan Chinnusamy, Kailash C Bansal
A sub-group of class I Caseinolytic proteases (Clps) function as molecular chaperone and confer thermotolerance to plants. We identified class I Clp family consisting of five ClpB/HSP100, two ClpC, and two ClpD genes from bread wheat. Phylogenetic analysis showed that these genes were highly conserved across grass genomes. Subcellular localization prediction revealed that TaClpC and TaClpD subgroup proteins and TaClpB1 proteins are potentially targeted to chloroplast, while TaClpB5 to mitochondria, and TaClpB2, TaClpB3, and TaClpB4 to cytoplasm...
2016: Frontiers in Plant Science
Joanna Krajewska, Zbigniew Arent, Daniel Więckowski, Michal Zolkiewski, Sabina Kędzierska-Mieszkowska
BACKGROUND: Leptospira interrogans is a spirochaete responsible for leptospirosis in mammals. The molecular mechanisms of the Leptospira virulence remain mostly unknown. Recently, it has been demonstrated that L. interrogans ClpB (ClpBLi) is essential for bacterial survival under stressful conditions and also during infection. The aim of this study was to provide further insight into the role of ClpB in L. interrogans and answer the question whether ClpBLi as a potential virulence factor may be a target of the humoral immune response during leptospiral infections in mammals...
2016: BMC Microbiology
Ana Paula Vaz Cassenego, Naira Elane Moreira de Oliveira, Marinella Silva Laport, Jaqueline Abranches, José A Lemos, Marcia Giambiagi-deMarval
The intrinsic ruggedness of Enterococcus faecalis is responsible for its widespread distribution in nature and is often viewed as an important virulence determinant. Previously, we showed that the ClpB ATPase is negatively regulated by CtsR and is required for thermotolerance and virulence in a Galleria mellonella invertebrate model. Here, we used in silico, Northern blot and quantitative real-time PCR analyses to identify additional members of the CtsR regulon, namely the clpP peptidase and the clpC and clpE ATPases...
September 2016: Antonie Van Leeuwenhoek
Ewa Pronicka, Dorota Piekutowska-Abramczuk, Elżbieta Ciara, Joanna Trubicka, Dariusz Rokicki, Agnieszka Karkucińska-Więckowska, Magdalena Pajdowska, Elżbieta Jurkiewicz, Paulina Halat, Joanna Kosińska, Agnieszka Pollak, Małgorzata Rydzanicz, Piotr Stawinski, Maciej Pronicki, Małgorzata Krajewska-Walasek, Rafał Płoski
BACKGROUND: Whole-exome sequencing (WES) has led to an exponential increase in identification of causative variants in mitochondrial disorders (MD). METHODS: We performed WES in 113 MD suspected patients from Polish paediatric reference centre, in whom routine testing failed to identify a molecular defect. WES was performed using TruSeqExome enrichment, followed by variant prioritization, validation by Sanger sequencing, and segregation with the disease phenotype in the family...
2016: Journal of Translational Medicine
Franca Rossi, Teresa Zotta, Lucilla Iacumin, Anna Reale
The understanding of the heat shock response (HSR) in lactobacilli from a regulatory point of view is still limited, though an increased knowledge on the regulation of this central stress response can lead to improvements in the exploitation of these health promoting microorganisms. Therefore the aim of this in silico study, that is the first to be carried out for members of the Lactobacillus genus, was predicting how HSR influences cell functions in the food associated and probiotic species Lactobacillus casei and Lactobacillus rhamnosus...
August 7, 2016: Journal of Theoretical Biology
Garbiñe Celaya, José Angel Fernández-Higuero, Ianire Martin, Germán Rivas, Fernando Moro, Arturo Muga
Chaperone-mediated protein aggregate reactivation is a complex reaction that depends on the sequential association of molecular chaperones on their interaction with protein aggregates and on substrate refolding. This process could be modulated by the highly crowded intracellular environment, which is known to affect protein conformational change, enzymatic activity, and protein-protein interactions. Here, we report that molecular crowding shapes the chaperone activity of bacterial disaggregase composed of the DnaK system (DnaK, DnaJ, and GrpE) and the molecular motor ClpB...
June 5, 2016: Journal of Molecular Biology
Jonathan Breton, Romain Legrand, Kirsti Akkermann, Anu Järv, Jaanus Harro, Pierre Déchelotte, Sergueï O Fetissov
OBJECTIVE: Caseinolytic protease B (ClpB) produced by Enterobacteria, such as Escherichia coli, has been identified as a conformational mimetic of α-melanocyte-stimulating hormone (α-MSH), an anorexigenic and anxiogenic neuropeptide. In mice, ClpB induces α-MSH cross-reactive antibodies and activates anorexigenic brain neurons. In patients with eating disorders (ED), anti-ClpB and anti-α-MSH antibodies correlate with psychopathological traits. However, it is not known if ClpB is present in human plasma including ED patients...
August 2016: International Journal of Eating Disorders
Ritesh Kumar, Amit Kumar Singh, Dhruv Lavania, Manzer H Siddiqui, Mohamed H Al-Whaibi, Anil Grover
Heat stress adversely affects the growth and yield of faba bean crop. Accumulation of ClpB/Hsp100 class of proteins is a critical parameter in induction of acquired heat stress tolerance in plants. Heat-induced expression of ClpB/Hsp100 genes has been noted in diverse plant species. Using primers complementary to soybean ClpB/Hsp100 gene, we analyzed the transcript expression profile of faba bean ClpB/Hsp100 gene in leaves of seedlings and flowering plants and in pollen grains. ClpB/Hsp100 protein accumulation profile was analyzed in leaves of faba bean seedlings using Arabidopsis thaliana cytoplasmic Hsp101 antibodies...
March 2016: Saudi Journal of Biological Sciences
H W Kim, M S Rhee
UNLABELLED: We previously showed that modeled microgravity conditions alter the physiological characteristics of Escherichia coli O157:H7. To examine how microgravity conditions affect bacterial heat stress responses, D values, membrane fatty acid composition, and heat stress-related gene expression (clpB, dnaK, grpE, groES, htpG, htpX, ibpB, and rpoH), E. coli O157:H7 ATCC 35150, ATCC 43889, ATCC 43890, and ATCC 43895 were cultured under two different conditions: low-shear modeled microgravity (LSMMG, an analog of spaceflight conditions) and normal gravity (NG, Earth-like conditions)...
May 15, 2016: Applied and Environmental Microbiology
JiaBei Lin, Aaron L Lucius
Escherichia coli caseinolytic peptidase B (ClpB) is a molecular chaperone with the unique ability to catalyze protein disaggregation in collaboration with the KJE system of chaperones. Like many AAA+ molecular motors, ClpB assembles into hexameric rings, and this reaction is thermodynamically linked to nucleotide binding. Here we show that ClpB exists in a dynamic equilibrium of monomers, dimers, tetramers, and hexamers in the presence of both limiting and excess ATPγS. We find that ClpB monomer is only able to bind one nucleotide, whereas all 12 sites in the hexameric ring are bound by nucleotide at saturating concentrations...
March 29, 2016: Biochemistry
Xia Zhao, Ruoyu Wang, Qianhan Shang, Haiting Hao, Yuyao Li, Yubao Zhang, Zhihong Guo, Yun Wang, Zhongkui Xie
Collagen-like proteins (CLPs) share the distinctive Gly-X-Thr repeating amino acid sequence of animal collagens, and contain N- and C-terminal domain making a collagen-like structure in Bacillus amyloliquefaciens FZB42, a plant growth-promoting rhizobacterium. Our previous study demonstrated that CLPs play important roles in biofilm construction and adherence to the surfaces on plant roots. However, bacterial localization of the CLPs remains unclear. Here, disrupted strains on all four clp genes (clpA, clpB, clpC and clpD) shown fewer filament than wild-type bacteria in extracellular matrix under scanning electron microscope (SEM)...
March 2016: Microbiological Research
Ana Paço, Clarisse Brígido, Ana Alexandre, Pedro F Mateos, Solange Oliveira
The ClpB chaperone is known to be involved in bacterial stress response. Moreover, recent studies suggest that this protein has also a role in the chickpea-rhizobia symbiosis. In order to improve both stress tolerance and symbiotic performance of a chickpea microsymbiont, the Mesorhizobium mediterraneum UPM-Ca36T strain was genetically transformed with pPHU231 containing an extra-copy of the clpB gene. To investigate if the clpB-transformed strain displays an improved stress tolerance, bacterial growth was evaluated under heat and acid stress conditions...
2016: PloS One
Michal Zolkiewski, Liudmila S Chesnokova, Stephan N Witt
Protein aggregation is a common problem in protein biochemistry and is linked to many cellular pathologies and human diseases. The molecular chaperone ClpB can resolubilize and reactivate aggregated proteins. This unit describes the procedure for following reactivation of an aggregated enzyme glucose-6-phosphate dehydrogenase mediated by ClpB from Escherichia coli in cooperation with another molecular chaperone, DnaK. The procedures for purification of these chaperones are also described.
2016: Current Protocols in Protein Science
Yasser A Elnakady, Indranil Chatterjee, Markus Bischoff, Manfred Rohde, Michaele Josten, Hans-Georg Sahl, Mathias Herrmann, Rolf Müller
PURPOSE: The emergence of bacteria that are resistant to many currently used drugs emphasizes the need to discover and develop new antibiotics that are effective against such multi-resistant strains. Kendomycin is a novel polyketide that has a unique quinone methide ansa structure and various biological properties. This compound exhibits strong antibacterial activity against Gram-negative and Gram-positive bacteria, including methicillin-resistant Staphylococcus aureus (MRSA). Despite the promise of kendomycinin in several therapeutic areas, its mode of action has yet to be identified...
2016: PloS One
Rina Rosenzweig, Patrick Farber, Algirdas Velyvis, Enrico Rennella, Michael P Latham, Lewis E Kay
ClpB/Hsp100 is an ATP-dependent disaggregase that solubilizes and reactivates protein aggregates in cooperation with the DnaK/Hsp70 chaperone system. The ClpB-substrate interaction is mediated by conserved tyrosine residues located in flexible loops in nucleotide-binding domain-1 that extend into the ClpB central pore. In addition to the tyrosines, the ClpB N-terminal domain (NTD) was suggested to provide a second substrate-binding site; however, the manner in which the NTD recognizes and binds substrate proteins has remained elusive...
December 15, 2015: Proceedings of the National Academy of Sciences of the United States of America
Jonathan Breton, Naouel Tennoune, Nicolas Lucas, Marie Francois, Romain Legrand, Justine Jacquemot, Alexis Goichon, Charlène Guérin, Johann Peltier, Martine Pestel-Caron, Philippe Chan, David Vaudry, Jean-Claude do Rego, Fabienne Liénard, Luc Pénicaud, Xavier Fioramonti, Ivor S Ebenezer, Tomas Hökfelt, Pierre Déchelotte, Sergueï O Fetissov
The composition of gut microbiota has been associated with host metabolic phenotypes, but it is not known if gut bacteria may influence host appetite. Here we show that regular nutrient provision stabilizes exponential growth of E. coli, with the stationary phase occurring 20 min after nutrient supply accompanied by bacterial proteome changes, suggesting involvement of bacterial proteins in host satiety. Indeed, intestinal infusions of E. coli stationary phase proteins increased plasma PYY and their intraperitoneal injections suppressed acutely food intake and activated c-Fos in hypothalamic POMC neurons, while their repeated administrations reduced meal size...
February 9, 2016: Cell Metabolism
Ratnesh Chandra Mishra, Richa, Amanjot Singh, Lalit Dev Tiwari, Anil Grover
Rice (Oryza sativa) ClpB-C (OsClpB-C) protein is expressed upon heat stress in vegetative tissues and constitutively in seeds. We produced stably transformed Arabidopsis plants carrying β-glucuronidase (Gus) reporter gene downstream to 1-kb OsClpB-C promoter (1kbPro plants). In the 1kbPro plants, expression of Gus transcript and protein followed the expression pattern of OsClpB-C gene in rice plants, i.e., heat induced in vegetative tissues and constitutive in seeds. Next, we produced transgenic Arabidopsis plants containing Gus downstream to 862-bp fragment of OsClpB-C promoter [lacking 138 nucleotides from 3' end of the 5'untranslated region (5'UTR); ∆UTR plants)...
March 2016: Cell Stress & Chaperones
Nan Wu, Lei He, Peng Cui, Wenjie Wang, Youhua Yuan, Shuang Liu, Tao Xu, Shanshan Zhang, Jing Wu, Wenhong Zhang, Ying Zhang
Despite the identification of many genes and pathways involved in the persistence phenomenon of bacteria, the relative importance of these genes in a single organism remains unclear. Here, using Escherichia coli as a model, we generated mutants of 21 known candidate persister genes and compared the relative importance of these mutants in persistence to various antibiotics (ampicillin, gentamicin, norfloxacin, and trimethoprim) at different times. We found that oxyR, dnaK, sucB, relA, rpoS, clpB, mqsR, and recA were prominent persister genes involved in persistence to multiple antibiotics...
2015: Frontiers in Microbiology
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