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Predicate | Object |
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rdf:type | |
lifeskim:mentions | |
pubmed:issue |
3
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pubmed:dateCreated |
1983-6-10
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pubmed:abstractText |
Sodium cholate at millimolar concentration is able to induce activity in rabbit muscle phosphorylase b in the absence of AMP. The maximum activation of the enzyme in presence of 7 mM sodium cholate was 24% of that achieved by 1 mM AMP. Other bile salts tested showed a negligible activating effect. The Ka for AMP was lowered fivefold by 5 mM of the steroid detergent, while the cooperative binding of the nucleotide was abolished. Phosphorylase b', a modified form of phosphorylase in which the phosphorylation site has been removed by limited tryptic attack, presented an activation profile similar to that of phosphorylase b. In contrast, phosphorylase a was inhibited by the bile salt, while the activity of liver phosphorylase b was not significantly affected. Modification of the AMP site of the enzyme with 2,3-butanedione could not inhibit sodium-cholate-induced activity. tert-Butanol, an organic solvent activator of phosphorylase b, was found to enhance the activity induced by sodium cholate. The interaction of sodium cholate and phosphorylase b was also followed by difference spectroscopy using a fluorescein isothiocyanate--phosphorylase b conjugate. Furthermore, measurements of electron spin resonance demonstrated that the mobility of a spin-label bound at buried--NH2 groups of phosphorylase b decreases cooperatively with increasing bile salt concentration.
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pubmed:language |
eng
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pubmed:journal | |
pubmed:citationSubset |
IM
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pubmed:chemical |
http://linkedlifedata.com/resource/pubmed/chemical/Adenosine Monophosphate,
http://linkedlifedata.com/resource/pubmed/chemical/Cholic Acid,
http://linkedlifedata.com/resource/pubmed/chemical/Cholic Acids,
http://linkedlifedata.com/resource/pubmed/chemical/Phosphorylase b,
http://linkedlifedata.com/resource/pubmed/chemical/Phosphorylases
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pubmed:status |
MEDLINE
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pubmed:month |
Apr
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pubmed:issn |
0014-2956
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pubmed:author | |
pubmed:issnType |
Print
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pubmed:day |
5
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pubmed:volume |
131
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pubmed:owner |
NLM
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pubmed:authorsComplete |
Y
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pubmed:pagination |
625-31
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pubmed:dateRevised |
2008-11-21
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pubmed:meshHeading |
pubmed-meshheading:6404625-Adenosine Monophosphate,
pubmed-meshheading:6404625-Animals,
pubmed-meshheading:6404625-Binding Sites,
pubmed-meshheading:6404625-Catalysis,
pubmed-meshheading:6404625-Chemical Phenomena,
pubmed-meshheading:6404625-Chemistry,
pubmed-meshheading:6404625-Cholic Acid,
pubmed-meshheading:6404625-Cholic Acids,
pubmed-meshheading:6404625-Enzyme Activation,
pubmed-meshheading:6404625-Kinetics,
pubmed-meshheading:6404625-Muscles,
pubmed-meshheading:6404625-Phosphorylase b,
pubmed-meshheading:6404625-Phosphorylases,
pubmed-meshheading:6404625-Rabbits
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pubmed:year |
1983
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pubmed:articleTitle |
Effect of sodium cholate on the catalytic and structural properties of phosphorylase b.
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pubmed:publicationType |
Journal Article
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