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Predicate | Object |
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rdf:type | |
lifeskim:mentions | |
pubmed:issue |
14
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pubmed:dateCreated |
1975-10-10
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pubmed:abstractText |
The equilibrium constant (KX) for the reaction D-serine dehydratase + pyridoxamine-P in equilibrium KX D-serine apodehydratase: pyridoxamine-P + pyridoxal-P was determined. At 25 degreees, pH 7.80, KX increases from 5.4 times 10-minus 5 to 21 times 10-minus 5 as T/2 is increased from 0.33 to 0.66. A value of 1.3 times 10-minus 4 M at 25 degrees, pH 7.80, T/2 0.33 for the equilibrium constant (KPMP) for dissociation of pyridoxamine-P from D-serine apodehydratase was determined from the ratio of the equilibrium constant for dissociation of pyridoxal-P from holoenzyme to KX. Pyridoxamine-P and the thiazolidine, formed from pyridoxal-P and cysteine, were found to have similar affinities for D-serine apodehydratase. Using the affinities of these derivatives as a measure of the noncovalent interactions between cofactor and protein, it was possible to estimate the contribution of the Schiff base linkage to the stability of the complex formed between pyridoxal-P and protein. The covalent Schiff base linkage in the holoenzyme was found to be no more stable than the Schiff base linkage formed between 6-aminocaproic acid and pyridoxal-P. The contribution of noncovalent interactions to the stability of the cofactor-protein complex was shown to be at least 20 to 40 times greater than the contribution of the covalent Schiff base linkage.
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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/L-Serine Dehydratase,
http://linkedlifedata.com/resource/pubmed/chemical/Organophosphorus Compounds,
http://linkedlifedata.com/resource/pubmed/chemical/Potassium Chloride,
http://linkedlifedata.com/resource/pubmed/chemical/Pyridoxal Phosphate,
http://linkedlifedata.com/resource/pubmed/chemical/Pyridoxamine,
http://linkedlifedata.com/resource/pubmed/chemical/Schiff Bases
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pubmed:status |
MEDLINE
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pubmed:month |
Jul
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pubmed:issn |
0021-9258
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pubmed:author | |
pubmed:issnType |
Print
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pubmed:day |
25
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pubmed:volume |
250
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pubmed:owner |
NLM
|
pubmed:authorsComplete |
Y
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pubmed:pagination |
5359-63
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pubmed:dateRevised |
2006-11-15
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pubmed:meshHeading |
pubmed-meshheading:1141234-Chromatography, Gel,
pubmed-meshheading:1141234-Kinetics,
pubmed-meshheading:1141234-L-Serine Dehydratase,
pubmed-meshheading:1141234-Organophosphorus Compounds,
pubmed-meshheading:1141234-Osmolar Concentration,
pubmed-meshheading:1141234-Potassium Chloride,
pubmed-meshheading:1141234-Pyridoxal Phosphate,
pubmed-meshheading:1141234-Pyridoxamine,
pubmed-meshheading:1141234-Schiff Bases,
pubmed-meshheading:1141234-Spectrophotometry, Ultraviolet
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pubmed:year |
1975
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pubmed:articleTitle |
Separation and evaluation of the covalent and noncovalent interactions which contribute to the binding of pyridoxal 5'-phosphate to D-serine apodehydratase.
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pubmed:publicationType |
Journal Article,
Research Support, U.S. Gov't, P.H.S.,
Research Support, U.S. Gov't, Non-P.H.S.
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