Linked Life Data

6389541

Source:http://linkedlifedata.com/resource/pubmed/id/6389541

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
22
pubmed:dateCreated
1984-12-27
pubmed:abstractText
To elucidate the role of individual amino acid residues in stabilizing the conformation of a protein, the stabilities of wild-type tryptophan synthase alpha-subunit from Escherichia coli and seven mutant proteins substituted by single amino acid residues at position 49, which is buried in the interior of the protein, were compared. The mutant proteins have Gln, Met, Val, Tyr, Leu, Ser, or Lys in place of Glu in the wild-type protein. The dissociation constant, pK, of the Glu residue at position 49 for the wild-type protein was determined to be 7.5 from a titration curve obtained by comparison of two-dimensional isoelectric focusing electrophoresis of the wild-type and mutant proteins. Our results indicate that 1) the conformational stabilities of the proteins studied increase linearly with hydrophobicity of the substituting residues (except Tyr), with the coefficient of this linear dependence being 2.0, 3.4, or 1.3 at pH 5.5, 7.0, or 9.0, respectively; and 2) Lys or Glu at position 49 serve as a destabilizing factor when ionized.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
25
pubmed:volume
259
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
14076-81
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1984
pubmed:articleTitle
Effect of amino acid residues on conformational stability in eight mutant proteins variously substituted at a unique position of the tryptophan synthase alpha-subunit.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't