Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
8
pubmed:dateCreated
1977-6-11
pubmed:abstractText
The catalytic subunit of rabbit skeletal muscle cyclic adenosine 3':5'-monophosphate-dependent protein kinase has been isolated in pure form. It has a molecular weight of 41,300, as determined by sedimentation equilibrium, which is in good agreement with the value of 41,000 determined by electrophoresis in the presence of sodium dodecyl sulfate. Sedimentation velocity determinations indicate that the subunit has an S20,w value of 3.12 which is essentially independent of protein concentration. These experiments are interpreted as indicating that the catalytic subunit dissociated from the holoenzyme exists as a monomer in solution. The least abundant amino acid is half-cystine, which was calculated to be present at 2.8 mol/mol of protein. The sulfhydryl reagents, N-ethylmaleimide, p-chloromercuribenzoic acid, and 5,5'-dithiobis(2-nitrobenzoic acid) inhibit the enzymatic activity of the subunit; inhibition by the two latter compounds can be reversed by 2-mercaptoethanol. Binding of 1 mol of N-ethylmaleimide/mol of protein results in almost complete inhibition. The isolated catalytic subunit contains 2.2 mol of tightly bound phosphate/mol of protein. Identification of either O-phosphoserine or O-phosphothreonine after partial acid hydrolysis indicates that at least part of the endogeneous phosphate exists as the phospho ester of one of these amino acids. Two peaks of catalytic activity corresponding to isoelectric points of pH 7.4 and 8.5 were identified by isoelectric focusing. Both forms utilize the same substrates and have similar sedimentation constants.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
25
pubmed:volume
252
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2691-7
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed:year
1977
pubmed:articleTitle
Purification and characterization of catalytic subunit of skeletal muscle adenosine 3':5'-monophosphate-dependent protein kinase.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.