The functionality of regions within the equatorial domain of Group II chaperonins is poorly understood. Previously we showed that a 70 amino acid sequence within this domain on the single-subunit recombinant thermosome from Methanocaldococcus jannaschii (rTHS) contains residues directly responsible for refolding protein substrates [L.M. Bergeron, C. Lee, D.S. Clark, Identification of a critical chaperoning region on an archaeal recombinant thermosome, Biochem. Biophys. Res. Commun. 369 (2008) 707-711]. In the present study, 6-aminopenicillanic acid (6-APA) was found to bind to rTHS and inhibit it from refolding proteins. Fluorescence anisotropy was used to measure a 6-APA/rTHS dissociation constant of 17.1 microM and verify that the binding site is within the first 70 amino-terminal rTHS residues. Docking simulations point to a specific loop region at residues 53-57 on rTHS as the most likely binding region. This loop region is located within the oligomeric association sites of the wild-type thermosome. These results implicate a specific equatorial region of Group II chaperonins in the refolding of proteins, and suggest its importance in conformational changes that accompany chaperone function.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.abb.2008.10.016 | DOI Listing |
J Biomol Struct Dyn
December 2024
Department of Bioinformatics, School of Life Sciences Pondicherry University, Puducherry, India.
Flavin adenine nucleotide (FAD)-dependent oxidoreductase enzyme Alcohol oxidase (AOX) facilitates the growth of methylotrophic yeast C. boidinii by catabolizing methanol, producing formaldehyde and hydrogen peroxide. Vacuolar Protease-A (PrA) from C.
View Article and Find Full Text PDFJ Biol Chem
December 2024
Physiology & Biomedical Engineering, Mayo Clinic College of Medicine & Science, Rochester, MN, 55906; Nephrology & Hypertension, Mayo Clinic College of Medicine & Science, Rochester, MN, 55906. Electronic address:
The chloride transporter-channel SLC26A9 is mediated by a reciprocal regulatory mechanism through the interaction between its cytoplasmic STAS domain and the R domain of CFTR. In vertebrate Slc26a9s, the STAS domain structures are interrupted by a disordered loop which is conserved in mammals but is variable in non-mammals. Despite the numerous studies involving the STAS domains in SLC26 proteins, the role of the disordered loop region has not been identified.
View Article and Find Full Text PDFSci Rep
December 2024
Department Gynecological Oncology, Sichuan Clinical Research Center for Cancer, Sichuan Cancer Hospital & Institute, Sichuan Cancer Center, Affiliated Cancer Hospital of University of Electronic Science and Technology of China, No. 55, Section 4, South People's Road, Chengdu, 610041, China.
MYD88 is an IL-6 primary response gene and, its upregulation of expression has been shown to be a poor prognostic factor in epithelial ovarian cancer (EOC). We investigated the effects of CpG methylation at the proximal promoter/5'UTR and IL-6/SP1/IRF1 signaling on upregulation of MYD88 and prognosis in EOC. We assessed CpG methylation at the proximal promoter/5'UTR of MYD88 using bisulfite sequencing/PCR in 103 EOC patients, 28 normal ovarian tissues and two EOC cell lines with differential expression of MYD88 and identified the impact of the level of CpG methylation on MYD88 upregulation by SP1/IRF1 with knockdown or blockade of IL-6.
View Article and Find Full Text PDFJ Fungi (Basel)
November 2024
Sir John Walsh Research Institute, Faculty of Dentistry, University of Otago, Dunedin 9016, New Zealand.
is intrinsically resistant to the widely used antifungal fluconazole, and therapeutic failure can result from acquired resistance to voriconazole, the primary treatment for invasive aspergillosis. The molecular basis of substrate specificity and innate and acquired resistance of to azole drugs were addressed using crystal structures, molecular models, and expression in of the sterol 14α-demethylase isoforms AfCYP51A and AfCYP51B targeted by azole drugs, together with their cognate reductase AfCPRA2 and AfERG6 (sterol 24-C-methyltransferase). As predicted by molecular modelling, functional expression of CYP51A and B required eburicol and not lanosterol.
View Article and Find Full Text PDFBiosensors (Basel)
December 2024
CUHKSZ-Boyalife Regenerative Medicine Engineering Joint Laboratory, School of Medicine, The Chinese University of Hong Kong, Shenzhen 518172, China.
The Phi29 DNA polymerase is renowned for its processivity in synthesizing single-stranded DNA amplicons by rolling around a circularized DNA template. However, DNA synthesis rolling circle amplification (RCA) is significantly hindered by the secondary structure in the circular template. To overcome this limitation, an engineered circular template without secondary structure could be utilized to improve the sensitivity of RCA-based assays without increasing its complexity.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!