Linked Life Data

2684979

Source:http://linkedlifedata.com/resource/pubmed/id/2684979

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
34
pubmed:dateCreated
1990-1-8
pubmed:abstractText
The entC and entA genes, coding for the enzymes isochorismate synthase and 2,3-dihydro-2,3-dihydroxybenzoate dehydrogenase, respectively, were subcloned behind the T7 promoter in the expression plasmid pGEM3Z. Their protein products were overproduced and partially purified for in vitro analysis of the conversion of chorismate to isochorismate. Whereas previous genetic experiments suggested that the EntA enzyme has a role in this conversion, this study clearly indicates that EntC alone catalyzes the reaction. Addition of EntA had no effect on isochorismate synthase activity. As a result, the mutation (previously designated entC401) in strain AN191 was characterized by nucleotide sequence analysis. The lesion is a single base substitution in the entA gene, resulting in a glutamic acid-for-glycine substitution at the penultimate amino acid (residue 247) of the EntA enzyme. The mutant protein was partially purified and shown to be devoid of 2,3-dihydro-2,3-dihydroxybenzoate dehydrogenase activity, whereas the entC gene product from strain AN191 exhibited normal isochorismate synthase function. These results conflict with the earlier characterization of the entC401 mutation in a different genetic background. The data presented herein establish that the EntA protein does not contribute to isochorismate synthase activity and that the mutant strain that led to this suggestion harbors a defective allele of entA rather than entC.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
5
pubmed:volume
264
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
20547-51
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed-meshheading:2684979-Base Sequence, pubmed-meshheading:2684979-Chorismic Acid, pubmed-meshheading:2684979-Cyclohexanecarboxylic Acids, pubmed-meshheading:2684979-Cyclohexenes, pubmed-meshheading:2684979-Escherichia coli, pubmed-meshheading:2684979-Escherichia coli Proteins, pubmed-meshheading:2684979-Genes, Bacterial, pubmed-meshheading:2684979-Genotype, pubmed-meshheading:2684979-Intramolecular Transferases, pubmed-meshheading:2684979-Isomerases, pubmed-meshheading:2684979-Isomerism, pubmed-meshheading:2684979-Kinetics, pubmed-meshheading:2684979-Molecular Sequence Data, pubmed-meshheading:2684979-Oxidoreductases, pubmed-meshheading:2684979-Oxidoreductases Acting on CH-CH Group Donors, pubmed-meshheading:2684979-Promoter Regions, Genetic, pubmed-meshheading:2684979-Restriction Mapping, pubmed-meshheading:2684979-Species Specificity
pubmed:year
1989
pubmed:articleTitle
The in vitro conversion of chorismate to isochorismate catalyzed by the Escherichia coli entC gene product. Evidence that EntA does not contribute to isochorismate synthase activity.
pubmed:affiliation
Department of Microbiology, School of Medicine, University of Missouri, Columbia 65212.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S.