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Predicate | Object |
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rdf:type | |
lifeskim:mentions | |
pubmed:issue |
3
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pubmed:dateCreated |
1983-1-19
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pubmed:abstractText |
Human muscle adenylate kinase (ATP:AMP phosphotransferase, EC 2.7.4.3.) was studied by 1H-nuclear magnetic resonance spectroscopy. The C-2 and C-4 proton resonances of the active-center histidine His-36 could be identified; the pK of His-36 was determined as 6.1. The pK of His-189 is very low (4.9) although it is located at the surface of the protein. Other resonance lines are discussed in comparison with NMR spectra of porcine adenylate kinase [McDonald et al. (1975) J. Biol. Chem. 250, 6947-6954]. A pH-dependent structural isomerization as shown by X-ray crystallography in the pig enzyme [Pai et al. (1977) J. Mol. Biol. 114, 37-45] was not observed for human adenylate kinase in solution. However, the binding of adenosine(5')pentaphospho(5')adenosine (Ap5A), a bisubstrate inhibitor, to adenylate kinase causes an overall change of the NMR spectrum indicative of a large conformational change of the enzyme. The exchange rate (koff) for Ap5A was estimated as 10 s-1 and decreases by addition of Mg2+. On the basis of these values and the known dissociation constant it is likely that the binding of Ap5A is a diffusion-controlled process kon being 10(8) M-1 s-1. In conclusion, the system Ap5A/Mg2+/human adenylate kinase, which has been studied by NMR spectroscopy and X-ray diffraction in parallel, is suitable for analyzing the induced fit postulated by Jencks for all kinase-catalyzed reactions.
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pubmed:language |
eng
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pubmed:journal | |
pubmed:citationSubset |
IM
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pubmed:chemical | |
pubmed:status |
MEDLINE
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pubmed:month |
Sep
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pubmed:issn |
0014-2956
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pubmed:author | |
pubmed:issnType |
Print
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pubmed:day |
1
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pubmed:volume |
126
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pubmed:owner |
NLM
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pubmed:authorsComplete |
Y
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pubmed:pagination |
531-6
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pubmed:dateRevised |
2007-7-23
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pubmed:meshHeading |
pubmed-meshheading:6291931-Adenylate Kinase,
pubmed-meshheading:6291931-Animals,
pubmed-meshheading:6291931-Humans,
pubmed-meshheading:6291931-Hydrogen-Ion Concentration,
pubmed-meshheading:6291931-Magnetic Resonance Spectroscopy,
pubmed-meshheading:6291931-Muscles,
pubmed-meshheading:6291931-Phosphotransferases,
pubmed-meshheading:6291931-Species Specificity,
pubmed-meshheading:6291931-Stereoisomerism,
pubmed-meshheading:6291931-Structure-Activity Relationship,
pubmed-meshheading:6291931-Swine
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pubmed:year |
1982
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pubmed:articleTitle |
The structural isomerisation of human-muscle adenylate kinase as studied by 1H-nuclear magnetic resonance.
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pubmed:publicationType |
Journal Article,
Research Support, Non-U.S. Gov't
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