ClpB is a heat-shock protein that reactivates aggregated proteins in cooperation with the DnaK chaperone system. ClpB belongs to the family of AAA+ ATPases and forms ring-shaped oligomers: heptamers in the absence of nucleotides and hexamers in the presence of nucleotides. We investigated the thermodynamic stability of ClpB in its monomeric and oligomeric forms. ClpB contains six distinct structural domains: the N-terminal domain involved in substrate binding, two AAA+ ATP-binding modules, each consisting of two domains, and a coiled-coil domain inserted between the AAA+ modules. We produced seven variants of ClpB, each containing a single Trp located in each of the ClpB domains and measured the changes in Trp fluorescence during the equilibrium urea-induced unfolding of ClpB. We found that two structural domains: the small domain of the C-terminal AAA+ module and the coiled-coil domain were destabilized in the oligomeric form of ClpB, which indicates that only those domains change their conformation and/or interactions during formation of the ClpB rings.
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http://dx.doi.org/10.1016/j.abb.2006.03.004 | DOI Listing |
Protein J
January 2025
Alliance Protein Laboratories, 13380 Pantera Road, San Diego, CA, 92130, USA.
The Ferguson plot is a simple method for determining the molecular weight of native proteins and their complexes. In this study, we tested the validity of the Ferguson plot based on agarose native gel electrophoresis using multimeric chaperone protein, ClpB, derived from a moderate halophile that forms a native hexamer. The Ferguson plot showed a single band with a molecular weight of 1,500 kDa, approximately twice the size of the native hexamer.
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December 2024
School of Basic Medicine, Guizhou University of Traditional Chinese Medicine, Guiyang, Guizhou, China.
Introduction: The mechanism of tannic acid (TA) intervention on methicillin-resistant (MRSA, USA 300) biofilm formation was explored using proteomics.
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Int J Mol Sci
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Guangzhou Key Laboratory of Forensic Multi-Omics for Precision Identification, School of Forensic Medicine, Southern Medical University, Guangzhou 510515, China.
Mechanical asphyxia presents a challenging diagnostic issue in forensic medicine due to its often covert nature, and the signs visible during an autopsy are usually not specific. Despite some progress in understanding hypoxia's effects, traditional methods' inherent limitations might overlook new biomarkers in mechanical asphyxia. This study employed 4D-DIA proteomics to explore the protein expression profiles of cardiac samples under conditions of mechanical asphyxia.
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December 2024
Department of Biochemistry and Molecular Biophysics, Kansas State University, 141 Chalmers Hall, Manhattan, KS, 66506, USA.
Plants (Basel)
November 2024
State Key Laboratory of Rice Biology and Breeding, Ministry of Agriculture Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Zhejiang Key Laboratory of Biology and Ecological Regulation of Crop Pathogens and Insects, Institute of Biotechnology, Zhejiang University, Hangzhou 310058, China.
Bacteriophage (phage) AP1 has been reported to effectively lyse , the causative agent of bacterial brown stripe in rice. However, phage AP1 exhibits strain-specific lysis patterns. In order to enhance the potential of phages for biological control of rice bacterial brown stripe, this study investigated the possible mechanism of strain-specific infection by characterizing phage AP1 and its susceptible (RS-2) and resistant (RS-1) strains.
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