Linked Life Data

10362535

Source:http://linkedlifedata.com/resource/pubmed/id/10362535

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1999-6-28
pubmed:abstractText
Human estrogenic 17beta-hydroxysteroid dehydrogenase (17beta-HSD1) plays a crucial role in the last step of the synthesis of estrogens. A detailed kinetic study demonstrated that the enzyme shows about 240 fold higher specificity towards estrone reduction than estradiol oxidation at physiological pH using tri-phosphate cofactors. The kcat/Km values are 96 +/- 10 and 0.4 +/- 0.1 s-1 (microM)-1 respectively for the above two reactions. However, it has been shown that this difference is closely linked to the use of NADPH and NADP cofactors. A binding study using equilibrium dialysis indicated similar KD (equilibrium dissociation constant) of 11 +/- 1 and 4.7 +/- 0.9 microM for estrone and estradiol, respectively. The binding affinity of 17beta-HSD1 to estrone was significantly increased with a KD of 1.6 +/- 0.2 microM in the presence of NADP, the latter used as an analogue of the NADPH. The results of binding studies agree with the steady-state kinetics, which showed that the Km of estrone is 12-fold lower when using NADPH as a cofactor than when using NADH. These results strongly suggest that the cofactor plays a crucial role in the stimulation of the specificity for estrogen reduction.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0006-291X
pubmed:author
pubmed:copyrightInfo
Copyright 1999 Academic Press.
pubmed:issnType
Print
pubmed:day
7
pubmed:volume
259
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
489-93
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1999
pubmed:articleTitle
Human estrogenic 17beta-hydroxysteroid dehydrogenase: predominance of estrone reduction and its induction by NADPH.
pubmed:affiliation
CHUL Research Center, Laval University, Quebec, Quebec, G1V 4G2, Canada.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't