Reference - Detail
|Author||Young IG, Leppik RA, Hamilton JA, Gibson F.|
|Title||Biochemical and genetic studies on ubiquinone biosynthesis in Escherichia coli K-12:4-hydroxybenzoate octaprenyltransferase.|
Three ubiquinone-deficient mutants of Escherichia coli unable to convert 4-hydroxybenzoate into 3-octaprenyl-4-hydroxybenzoate were isolated and examined. The results of genetic analysis suggest that each of the mutants carries a mutation in a gene designated ubiA which can be represented at minute 79 on the E. coli chromosome map. The conversion of 4-hydroxybenzoate into 3-octaprenyl-4-hydroxybenzoate, catalyzed by 4-hydroxybenzoate octaprenyltransferase, was studied with a strain of E. coli that is blocked in the common pathway of aromatic biosynthesis and consequently accumulates the precursor of the side chain of ubiquinone. Both the side-chain precursor and 4-hydroxybenzoate octaprenyltransferase were shown to be membrane-bound. The enzyme required Mg(2+) for optimal activity. The ubiA(-) mutants were found to lack 4-hydroxybenozate octaprenyltransferase activity, which suggested that the ubiA gene is the structural gene coding for this enzyme.
|MeSH||Alkyl and Aryl Transferases Benzoates / pharmacology Carbon Isotopes Chromatography, Thin Layer Chromosome Mapping Coliphages Enzyme Activation Escherichia coli / drug effects Escherichia coli / enzymology* Escherichia coli / growth & development Genes Genetics, Microbial Kinetics Magnesium / pharmacology Mutation Subcellular Fractions / drug effects Subcellular Fractions / enzymology Terpenes Transduction, Genetic Transferases* Ubiquinone / biosynthesis*|
|Prokaryotes E. coli||ME5454|