Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
32
pubmed:dateCreated
1999-9-8
pubmed:abstractText
The NAD-malic enzyme cDNA has been subcloned into the pQE expression vector, expressed with a six-His tag, and purified. The His-tagged enzyme is purified by a combination of Ni-NTA and orange A agarose column chromatography with a yield of 45% and an estimated purity of >90%. The tag and linker have no effect on the kinetic parameters of the enzyme compared to the wild-type enzyme. Alanine-scanning site-directed mutagenesis has been carried out on all of the conserved neutral acid residues of the NAD-malic enzyme from Ascaris suum. Data obtained confirm the predicted role of D178 and D295 in metal ion binding, the likely role of D294, D361, and E440 in the NAD binding site, and the role of E58 and D272 in malate binding. Decreases in V/E(t) by 10(4)-fold and in V/K(malate)E(t) by 10(7)-fold, when D295 is changed to alanine, suggest that it is a likely candidate for the general base that accepts a proton from the malate hydroxyl in the oxidation step.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
10
pubmed:volume
38
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
10527-32
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1999
pubmed:articleTitle
Mapping the active site topography of the NAD-malic enzyme via alanine-scanning site-directed mutagenesis.
pubmed:affiliation
Department of Chemistry and Biochemistry, University of Oklahoma, Norman 73019, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't