Linked Life Data

21557325

Source:http://linkedlifedata.com/resource/pubmed/id/21557325

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
7
pubmed:dateCreated
2011-6-14
pubmed:abstractText
Protecting osmolytes are widespread small organic molecules able to stabilize the folded state of most proteins against various denaturing stresses in vivo. The osmophobic model explains thermodynamically their action through a preferential exclusion of the osmolyte molecules from the protein surface, thus favoring the formation of intrapeptide hydrogen bonds. Few works addressed the influence of protecting osmolytes on the protein unfolding transition state and kinetics. Among those, previous single molecule force spectroscopy experiments evidenced a complexation of the protecting osmolyte molecules at the unfolding transition state of the protein, in apparent contradiction with the osmophobic nature of the protein backbone. We present single-molecule evidence that glycerol, which is a ubiquitous protecting osmolyte, stabilizes a globular protein against mechanical unfolding without binding into its unfolding transition state structure. We show experimentally that glycerol does not change the position of the unfolding transition state as projected onto the mechanical reaction coordinate. Moreover, we compute theoretically the projection of the unfolding transition state onto two other common reaction coordinates, that is, the number of native peptide bonds and the weighted number of native contacts. To that end, we augment an analytic Ising-like protein model with support for group-transfer free energies. Using this model, we find again that the position of the unfolding transition state does not change in the presence of glycerol, giving further support to the conclusions based on the single-molecule experiments.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
1097-0134
pubmed:author
pubmed:copyrightInfo
Copyright © 2011 Wiley-Liss, Inc.
pubmed:issnType
Electronic
pubmed:volume
79
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2214-23
pubmed:meshHeading
pubmed:year
2011
pubmed:articleTitle
Observing the osmophobic effect in action at the single molecule level.
pubmed:affiliation
Department of Biochemistry G.Moruzzi, University of Bologna, Via Irnerio 48, 40126 Bologna, Italy.
pubmed:publicationType
Journal Article