Linked Life Data

9851711

Source:http://linkedlifedata.com/resource/pubmed/id/9851711

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1998-12-28
pubmed:abstractText
The amino acid residues involved in the metal-binding site in the iron-containing dehydrogenase family were characterized by the site-directed mutagenesis of selected candidate residues of propanediol oxidoreductase from Escherichia coli. Based on the findings that mutations H263R, H267A and H277A resulted in iron-deficient propanediol oxidoreductases without catalytic activity, we identified three conserved His residues as iron ligands, which also bind zinc. The Cys362, a residue highly conserved among these dehydrogenases, was considered another possible ligand by comparison with the sequences of the medium-chain dehydrogenases. Mutation of Cys362 to Ile, resulted in an active enzyme that was still able to bind iron, with minor changes in the Km values and decreased thermal stability. Furthermore, in an attempt to produce an enzyme specific only for the zinc ion, three mutations were designed to mimic the catalytic zinc-binding site of the medium-chain dehydrogenases: (1) V262C produced an enzyme with altered kinetic parameters which nevertheless retained a significant ability to bind both metals, (2) the double mutant V262C-M265D was inactive and too unstable to allow purification, and (3) the insertion of a cysteine at position 263 resulted in a catalytically inactive enzyme without iron-binding capacity, while retaining the ability to bind zinc. This mutation could represent a conceivable model of one of the steps in the evolution from iron to zinc-dependent dehydrogenases.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0014-2956
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
258
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
207-13
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
1998
pubmed:articleTitle
Site-directed mutagenesis studies of the metal-binding center of the iron-dependent propanediol oxidoreductase from Escherichia coli.
pubmed:affiliation
Department de Bioquímica Facultat de Farmàcia, Universitat de Barcelona, Spain.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't