Linked Life Data

17034927

Source:http://linkedlifedata.com/resource/pubmed/id/17034927

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2006-12-25
pubmed:abstractText
17beta-Hydroxysteroid dehydrogenase from the fungus Cochliobolus lunatus (17beta-HSDcl) is an NADPH-dependent member of the short-chain dehydrogenase/ reductase superfamily. To study the catalytic properties of this enzyme, we prepared several specific mutations of 17beta-HSDcl (Tyr167Phe, His164Trp/Gly, Tyr212Ala). Wild-type 17beta-HSDcl and the 17beta-HSDcl mutants were evaluated by chromatographic, kinetic and thermodynamic means. The Tyr167Phe mutation resulted in a complete loss of enzyme activity, while substitution of His164 with Trp and Gly both resulted in higher specificity number (V/K) for the steroid substrates, which are mainly a consequence of easier accessibility of steroid substrates to the active-site hollow under optimized conditions. The Tyr212Ala mutant showed increased activity in the oxidative direction, which appears to be a consequence of increased NADPH dissociation. The kinetic characterizations and thermodynamic analyses also suggest that His164 and Tyr212 in 17beta-HSDcl have a role in the opening and closing of the active site of this enzyme and in the discrimination between oxidized and reduced coenzyme.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0300-9084
pubmed:author
pubmed:issnType
Print
pubmed:volume
89
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
63-71
pubmed:meshHeading
pubmed:year
2007
pubmed:articleTitle
His164 regulates accessibility to the active site in fungal 17beta-hydroxysteroid dehydrogenase.
pubmed:affiliation
Institute of Biochemistry, Medical Faculty, University of Ljubljana, Vrazov trg 2, 1000 Ljubljana, Slovenia.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't