Linked Life Data

6486798

Source:http://linkedlifedata.com/resource/pubmed/id/6486798

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1984-11-1
pubmed:abstractText
The enzymes of the purine nucleotide cycle-AMP deaminase, adenylosuccinate synthetase, and adenylosuccinate lyase-were examined as a functional unit in an in vitro system which simulates the purine nucleotide composition of sarcoplasm. Activity of each cycle enzyme in extracts of rat skeletal muscle was observed to increase as ATP/ADP, reflecting the energy state of the system, was lowered from approximately 50 to 1. The increase in AMP deaminase activity could be attributed to effects of energy state and factors such as AMP concentration, which are obligatorily coupled to energy state. The increases in synthetase and lyase activities were accounted for by increases in the concentration of IMP and adenylosuccinate, respectively. The inhibitory influence of IMP concentration on synthetase activity reported in other systems was not observed in this system; synthetase activity progressively increased as IMP concentration was raised to approximately 4 mM, and apparent saturation occurred at concentrations above 4 mM. Also, adenylosuccinate was found to be an activator of AMP deaminase. The results of this study document that the activities of the enzymes of the purine nucleotide cycle increase in parallel at low energy states, and the components of the cycle function as a coordinated unit with individual enzyme activities linked via concentrations of cycle intermediates.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0003-9861
pubmed:author
pubmed:issnType
Print
pubmed:volume
233
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
515-29
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1984
pubmed:articleTitle
Control of the purine nucleotide cycle in extracts of rat skeletal muscle: effects of energy state and concentrations of cycle intermediates.
pubmed:publicationType
Journal Article, In Vitro, Research Support, U.S. Gov't, P.H.S.