Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
2001-5-7
pubmed:abstractText
Molecular dynamics simulations were conducted to estimate the free energy barrier of unfolding surfactant-associated polypeptide C (SP-C) from an alpha-helical conformation. Experimental studies indicate that while the helical fold of SP-C is thermodynamically stable in phospholipid micelles, it is metastable in a mixed organic solvent of CHCl3/CH3OH/0.1 M HCl at 32:64:5 (v/v/v), in which it undergoes an irreversible transformation to an insoluble aggregate that contains beta-sheet. On the basis of experimental observations, the free energy barrier was estimated to be approximately 100 kJ/mole by applying Eyring's transition state theory to the experimental rate of unfolding [Protein Sci 1998;7:2533-2540]. These studies prompted us to carry out simulations to investigate the unwinding process of two helical turns encompassing residues 25-32 in water and in methanol. The results give an upper bound estimation for the free energy barrier of unfolding of SP-C of approximately 20 kJ/mole. The results suggest a need to reconsider the applicability of a single-mode activated process theory to protein unfolding.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0887-3585
pubmed:author
pubmed:copyrightInfo
Copyright 2001 Wiley-Liss, Inc.
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
43
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
395-402
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2001
pubmed:articleTitle
Free energy barrier estimation of unfolding the alpha-helical surfactant-associated polypeptide C.
pubmed:affiliation
Groningen Biomolecular Sciences and Biotechnology Institute, Department of Biophysical Chemistry, University of Groningen, Groningen, The Netherlands.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't