Linked Life Data

8688416

Source:http://linkedlifedata.com/resource/pubmed/id/8688416

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
27
pubmed:dateCreated
1996-8-26
pubmed:abstractText
The dimeric calcium-binding protein S100b is proposed to undergo a calcium-induced structural change allowing it to interact, via a hydrophobic surface, with other proteins. Previously it has been suggested that calcium binding to S100b leads to the exposure of at least one phenylalanine residue (Mani et al., 1982, 1983). This effect appears to be "reversed" at higher ionic strength, leading to a possible reburying of phenylalanine residues (Mani et al., 1982, 1983). To study these effects, we monitored calcium binding to recombinant human S100b by NMR spectroscopy under different salt (KCI) conditions. 15N-Labeled glycine residues in S100b showed calcium-induced chemical shift changes similar to those reported for the related monomeric protein calbindin D9k, suggesting similar conformational changes are occurring in the calcium-binding loops of these two proteins. Calcium binding to S100b also resulted in a shifting and broadening of several 1H resonances from the Ca-S100b form only including those from the side chains of residues F14, F70, and F73 but not those of residue Y17. This broadening was enhanced with increased ionic strength (KCI). However, small additions ( < 15% v/v) of the hydrophobic solvent trifluoroethanol relieved this phenomenon, leading to narrower line widths. These observations are consistent with the calcium-induced exposure of at least one of these hydrophobic residues, resulting in self-association of the S100b dimer. Trifluoroethanol serves to dissociate these complexes back to the dimeric calcium species. We propose that this cluster of hydrophobic residues which include F14, F73, and F88 may be important for interactions with a target protein.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
9
pubmed:volume
35
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
8805-14
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1996
pubmed:articleTitle
Structural influence of cation binding to recombinant human brain S100b: evidence for calcium-induced exposure of a hydrophobic surface.
pubmed:affiliation
Department of Biochemistry, University of Western Ontario, London, Canada.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't