Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
1977-4-15
pubmed:abstractText
Acetimidylation of the amino groups of alcohol dehydrogenase from human and horse liver yields several modified enzyme forms, which differ in electrophoretic mobility and can be separated by ion exchange chromatography, but which are similar in kinetic characteristics. The acetimidylated, as well as the methylated, enzymes from human livers of the normal phenotype have increased activity and larger Michaelis and inhibition constants. These results suggest that the human enzyme has amino groups at the active sites, as was shown previously for the horse enzyme. The variant subunit occuring in the enzyme isolated from atypical human livers does not seem to be activated by acetimidylation, which may indicate that substitution of proline for Ala-230 or modifiction of Lys-228 is sufficient to fully activate the enzyme. Results of product inhibition studies of native and modified human enzymes are consistent with an Ordered Bi Bi mechanism. However, the major isoenzyme of native human liver alcohol, dehydrogenase exhibits nonlinear kinetics over a wide range of ethanol concentrations. This result may indicate that subunits with different kinetic characteristics are present or that there is negative cooperativity between subunits. After chemical modification, the kinetic patterns become linear, suggesting that the mechanism is altered.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
25
pubmed:volume
252
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1464-70
pubmed:dateRevised
2009-10-27
pubmed:meshHeading
pubmed:year
1977
pubmed:articleTitle
Characterization and kinetics of native and chemically acitvated human liver alcohol dehydrogenases.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, Non-P.H.S.