title: The organization of the leuC, leuD and leuB genes of the extreme thermophile Thermus thermophilus.
abstract: 3-Isopropylmalate dehydrogenase is encoded by leuB gene while leuC and leuB genes encode the large and small subunits of isopropylmalate isomerase in leucine biosynthetic pathway, respectively. Organization of the leuB, leuC and leuD genes of an extreme thermophile, Thermus thermophilus, was investigated by sequence analysis. Location of the genes was also tested by complementation analysis of leu deficiency of the thermophile and Escherichia coli. The order was the leuC, leuD, and leuB genes and, in contrast to a previous report, they did not overlap with each other. Sequence analysis of the leuC and leuD genes suggested that cysteine residues for iron-sulfur binding and other amino acid residues involved in isomerase activity, which have been inferred from analysis of a related protein, aconitase, were highly conserved.
authors.affiliation: Department of Molecular Biology, Tokyo University of Pharmacy & Life Science, 1432 Horinouchi, Hachioji, Tokyo 192-0392, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Tamakoshi
authors.forename: A
authors.initials: A
authors.lastname: Yamagishi
authors.forename: T
authors.initials: T
authors.lastname: Oshima
mesh_terms: D050539:3-Isopropylmalate Dehydrogenase; D000429:Alcohol Oxidoreductases / Q000096:biosynthesis / Q000235:genetics*; D000595:Amino Acid Sequence; D001483:Base Sequence; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics; D005798:Genes, Bacterial; D005816:Genetic Complementation Test; D005822:Genetic Vectors; D006358:Hot Temperature; D007930:Leucine / Q000096:biosynthesis; D008969:Molecular Sequence Data; D011994:Recombinant Proteins / Q000096:biosynthesis; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D013045:Species Specificity; D016963:Thermus thermophilus / Q000201:enzymology / Q000235:genetics*
chemical_list: D011994:Recombinant Proteins; D000429:Alcohol Oxidoreductases; D050539:3-Isopropylmalate Dehydrogenase; D007930:Leucine