Linked Life Data

7824524

Source:http://linkedlifedata.com/resource/pubmed/id/7824524

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1995-2-10
pubmed:abstractText
Theoretical estimations of changes in side chain configurational entropy are essential for understanding the different contributions to the overall thermodynamic behavior of important biological processes like folding and binding. The configurational entropy of any given side chain in any particular protein can be evaluated from the complete energy profile of the side chain. Calculations of the energy profiles can be performed using the side chain single bond dihedrals as the only independent variables as long as the structures at each value of the dihedrals are allowed to relax through small changes in the valence bond angles. The probabilities of different side chain conformers obtained from these energy profiles are very similar to the conformer populations obtained by analysis of side chain preferences in the proteins of the Protein Data Bank. Also, side chain conformational entropies obtained from the energy profiles agree extremely well with those obtained from the Protein Data Bank conformer populations. Changes in side chain configurational entropy in binding and folding can be computed as differences in conformational entropy because, in most cases, the frequency of the rotational oscillation around the energy minimum of any given conformer does not appear to change significantly in the reactions. Changes of side chain conformational entropy calculated in this way were compared with experimental values. The only available experimental data--the effect of side chain substitution on the stability of alpha-helices--were used for this comparison. The experimental values were corrected to subtract the solvent contributions. This comparison yields an excellent agreement between calculated and experimental values, validating not only the theoretical estimates but also the separability of the entropic contributions into configurational terms and solvation related terms.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0887-3585
pubmed:author
pubmed:issnType
Print
pubmed:volume
20
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
68-84
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1994
pubmed:articleTitle
Estimation of changes in side chain configurational entropy in binding and folding: general methods and application to helix formation.
pubmed:affiliation
Department of Biophysics, School of Medicine, Johns Hopkins University, Baltimore, Maryland 21218.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.