Linked Life Data

16826551

Source:http://linkedlifedata.com/resource/pubmed/id/16826551

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:dateCreated
2006-8-21
pubmed:abstractText
Cold-induced conformational transition of ubiquitin was studied at pH 4.5 under a constant pressure of 2 kbar using variable pressure one-dimensional 1H and two-dimensional 15N/1H NMR spectroscopy as well as IR spectroscopy. Although a tendency for preferential stabilization of a peculiar locally disordered and partially hydrated conformer I, identical with that previously found with variable-pressure NMR at 0 degrees C, is recognized, the transition of the folded conformer N to the unfolded conformer U occurs largely cooperatively with decreasing temperature, reaching near completion at - 21 degrees C. NMR spectral features as well as the analysis of NMR relaxation parameters indicate that the polypeptide chain is almost fully unfolded, fairly well-hydrated and floppy at - 21 degrees C, whereas the IR spectrum shows a substantial decrease of the beta-sheet. The Gibbs energy change from the folded state (a mixture of N and I) to the unfolded state at 2 kbar obtained from the 1H NMR data is fitted well with a single DeltaCp value of 2.43 +/- 0.13 (kJ/K mol) for the entire temperature range between - 21 and 90 degrees C, covering both the cold denaturation and heat denaturation, showing that the two denatured states actually belong to a single thermodynamic phase of the protein. The DeltaCp value determined at 2 kbar is substantially smaller than the DeltaCp determined at 1 bar (3.8-5.8 (kJ/Kmol), which is consistent with the fact that the denaturation takes place from a mixture of N and I at 2 kbar rather than from pure N at 1 bar.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0749-1581
pubmed:author
pubmed:copyrightInfo
Copyright 2006 John Wiley & Sons, Ltd.
pubmed:issnType
Print
pubmed:volume
44 Spec No
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
S108-13
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
2006
pubmed:articleTitle
Cold denaturation of ubiquitin at high pressure.
pubmed:affiliation
RIKEN SPring-8 Center, RIKEN Harima Institute, 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5148, Japan.
pubmed:publicationType
Journal Article