Linked Life Data

1654322

Source:http://linkedlifedata.com/resource/pubmed/id/1654322

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
26
pubmed:dateCreated
1991-10-21
pubmed:abstractText
A recombinant protein-tyrosine-phosphatase has been expressed in Escherichia coli and purified to a single band by sodium dodecyl sulfate-polyacrylamide gel electrophoresis using affinity chromatography. When the phosphatase was allowed to react with 32P-labeled substrates and then rapidly denaturated, a 32P-labeled phosphoprotein could be visualized by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Transient formation of a 32P-labeled phosphoprotein was observed, and the 32P-labeled protein disappeared as substrate was consumed. In the presence of 32P-labeled p-nitrophenyl phosphate, 0.27 mol of phosphate was incorporated per mol of protein-tyrosine-phosphatase. Site-directed mutagenesis of a catalytically essential cystine residue (position 215) in the recombinant protein resulted in an inactive enzyme, and no phosphoprotein was formed. The 32P-labeled phosphoprotein showed a maximum lability between pH 2.5 and 3.5 and was rapidly decomposed in the presence of iodine. These properties, along with additional site-directed mutations, suggest that the protein-tyrosine-phosphatase forms a covalent thiol phosphate linkage between Cys215 and phosphate.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
266
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
17026-30
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:year
1991
pubmed:articleTitle
Evidence for protein-tyrosine-phosphatase catalysis proceeding via a cysteine-phosphate intermediate.
pubmed:affiliation
Department of Biochemistry, Purdue University, West Lafayette, Indiana 47907.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't