| The role of a disulfide bridge in the stability and folding kinetics of Arabidopsis thaliana cytochrome c(6A). | |
| | |
MedLine Citation:
|
PMID: 22085909 Owner: NLM Status: Publisher |
Abstract/OtherAbstract:
|
Cytochrome c(6A) is a eukaryotic member of the Class I cytochrome c family possessing a high structural homology with photosynthetic cytochrome c(6) from cyanobacteria, but structurally and functionally distinct through the presence of a disulfide bond and a heme mid-point redox potential of +71mV (vs normal hydrogen electrode). The disulfide bond is part of a loop insertion peptide that forms a cap-like structure on top of the core α-helical fold. We have investigated the contribution of the disulfide bond to thermodynamic stability and (un)folding kinetics in cytochrome c(6A) from Arabidopsis thaliana by making comparison with a photosynthetic cytochrome c(6) from Phormidium laminosum and through a mutant in which the Cys residues have been replaced with Ser residues (C67/73S). We find that the disulfide bond makes a significant contribution to overall stability in both the ferric and ferrous heme states. Both cytochromes c(6A) and c(6) fold rapidly at neutral pH through an on-pathway intermediate. The unfolding rate for the C67/73S variant is significantly increased indicating that the formation of this region occurs late in the folding pathway. We conclude that the disulfide bridge in cytochrome c(6A) acts as a conformational restraint in both the folding intermediate and native state of the protein and that it likely serves a structural rather than a previously proposed catalytic role. |
| | |
Authors:
|
Jody M Mason; Derek S Bendall; Christopher J Howe; Jonathan A R Worrall |
Related Documents
:
|
21875799 - Cellular uptake of aib-containing amphipathic helix peptide. 21818369 - Peptide substrates for rho-associated kinase 2 (rho-kinase 2/rock2). 22094809 - Evolution of disulfide-rich peptide aptamers using cdna display. 22051539 - Recombinant medaka (oryzias melastigmus) pro-hepcidin: multifunctional characterization. 18667849 - Cloning, expression, and characterization of a new phytase from the phytopathogenic bac... 21763489 - The conformation and orientation of a 27-residue ccr5 peptide in a ternary complex with... 22543859 - A general solid phase method for the synthesis of sequence independent peptidyl-fluorom... 2887569 - Product inhibition of carboxypeptidase h. 8224239 - Molecular cloning of cdna for the 29 kda proteinase participating in decomposition of t... |
Publication Detail:
|
Type: JOURNAL ARTICLE Date: 2011-10-31 |
Journal Detail:
|
Title: Biochimica et biophysica acta Volume: - ISSN: 0006-3002 ISO Abbreviation: - Publication Date: 2011 Oct |
Date Detail:
|
Created Date: 2011-11-16 Completed Date: - Revised Date: - |
Medline Journal Info:
|
Nlm Unique ID: 0217513 Medline TA: Biochim Biophys Acta Country: - |
Other Details:
|
Languages: ENG Pagination: - Citation Subset: - |
Copyright Information:
|
Copyright © 2011. Published by Elsevier B.V. |
Affiliation:
|
Department of Biological Sciences, University of Essex, Wivenhoe Park, Colchester, CO4 3SQ, UK. |
Export Citation:
|
APA/MLA Format Download EndNote Download BibTex |
| MeSH Terms | |
Descriptor/Qualifier:
|
|
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
Previous Document: A lateral flow biosensor for detection of nucleic acids with high sensitivity and selectivity.
Next Document: DPOFA, a Cl-/HCO3- exchanger antagonist, stimulates fluid absorption across basolateral surface of ...