Linked Life Data

2164013

Source:http://linkedlifedata.com/resource/pubmed/id/2164013

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
20
pubmed:dateCreated
1990-8-14
pubmed:abstractText
Polyphosphate kinase (PPK) polymerizes the terminal phosphate of ATP to a long chain polyphosphate (poly(P) or (Pi)n) in a freely reversible reaction (Kornberg, S. R. (1957) Biochim. Biophys. Acta 26, 294-300), nATP in equilibrium nADP + (Pi)n, PPK, now purified to homogeneity, is a tetramer of 69-kDa subunits. Addition of a primer in the synthetic reaction is not required, nor does ATP or inorganic orthophosphate (Pi) serve in this role. PPK is autophosphorylated under the conditions of poly(P) synthesis; Pi is linked by a nitrogen-phosphate bond as judged by its acid lability and alkali stability. Incorporation of phosphate from the isolated phosphoenzyme into poly(P) upon the addition of ATP in the synthetic reaction and its incorporation into ATP upon the addition of ADP indicate phosphoenzyme to be an intermediate in the reaction. At an ATP level of 5 microM, well below its Km of 2 mM, a pronounced lag in poly(P) synthesis can be removed by tetrapolyphosphate but not by Pi, PPi, or tripolyphosphate. The basis for this stimulatory effect is not clear inasmuch as tetrapolyphosphate does not promote the dephosphorylation of the presumed phosphoenzyme intermediate.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
265
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
11734-9
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1990
pubmed:articleTitle
Polyphosphate kinase from Escherichia coli. Purification and demonstration of a phosphoenzyme intermediate.
pubmed:affiliation
Department of Biochemistry, Stanford University School of Medicine, California 94305-5307.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S.