Linked Life Data

10660568

Source:http://linkedlifedata.com/resource/pubmed/id/10660568

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
2000-3-16
pubmed:abstractText
Heparin regulates the inhibitory activity of antithrombin. It has been proposed that residues P15 and P14 are expelled from beta-sheet A of antithrombin by heparin binding, permitting better interaction of the reactive center loop with factor Xa. We have made a P14 antithrombin variant (S380E) to create an activated inhibitory form of antithrombin in which P14 is already expelled from beta-sheet A. S380E antithrombin fluorescence is enhanced 35 +/- 5% compared with control antithrombin. There is minimal further increase in antithrombin fluorescence upon heparin binding. The variant has a 5 degrees C lower T(m) than control antithrombin. The variant is an inhibitor of proteinases and has a nearly 200-fold increased basal rate of inhibition of factor Xa, after correction for an increased stoichiometry of inhibition. This is comparable to that of antithrombin activated by high affinity heparin pentasaccharide. Full-length high affinity heparin causes only a 7-fold additional increase in rate and a large increase in stoichiometry of inhibition. In contrast, the basal rate of inhibition of thrombin is similar to that of control antithrombin but is increased 300-fold by heparin. These findings suggest that the native state of the S380E variant exists in a loop-expelled conformation that is consequently highly reactive toward factor Xa.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
11
pubmed:volume
275
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
4092-8
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
2000
pubmed:articleTitle
Serine 380 (P14) --> glutamate mutation activates antithrombin as an inhibitor of factor Xa.
pubmed:affiliation
Department of Biochemistry and Molecular Biology, University of Illinois at Chicago, Chicago, Illinois 60612, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.