Linked Life Data

6415289

Source:http://linkedlifedata.com/resource/pubmed/id/6415289

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1983-12-17
pubmed:abstractText
The binding sites for the allosteric activator, AMP, to glycogen phosphorylase b are described in detail utilizing the more precise knowledge of the native structure obtained from crystallographic restrained least-squares refinement than has hitherto been available. Localized conformational changes are seen at the allosteric effector site that include shifts of between 1 and 2 A for residues Tyr75 and Arg309 and very small shifts for the region of residues 42 to 44 from the symmetry-related subunit. Kinetic studies demonstrate that NADH inhibits the AMP activation of glycogen phosphorylase b. Crystallographic binding studies at 3.5 A resolution show that NADH binds to the same sites on the enzyme as AMP, i.e. the allosteric effector site N, which is close to the subunit-subunit interface, and the nucleoside inhibitor site I, which is some 12 A from the catalytic site. The conformations of NADH at the two sites are different but both conformations are "folded" so that the nicotinamide ring is close (approx. 6 A) to the adenine ring. These conformations are compared with those suggested from solution studies and with the extended conformations observed in the single crystal structure of NAD+ and for NAD bound to dehydrogenases. Possible mechanisms for NADH inhibition of phosphorylase activation are discussed.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0022-2836
pubmed:author
pubmed:issnType
Print
pubmed:day
25
pubmed:volume
170
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
529-65
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1983
pubmed:articleTitle
Comparison of AMP and NADH binding to glycogen phosphorylase b.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't