title: The ispB gene encoding octaprenyl diphosphate synthase is essential for growth of Escherichia coli.
abstract: The Escherichia coli ispB gene encoding octaprenyl diphosphate synthase is responsible for the synthesis of the side chain of isoprenoid quinones. We tried to construct an E. coli ispB-disrupted mutant but could not isolate the chromosomal ispB disrupted mutant unless the ispB gene or its homolog was supplied on a plasmid. The chromosomal ispB disruptants that harbored plasmids carrying the ispB homologs from Haemophilus influenzae and Synechocystis sp. strain PCC6803 produced mainly ubiquinone 7 and ubiquinone 9, respectively. Our results indicate that the function of the ispB gene is essential for normal growth and that this function can be substituted for by homologs of the ispB gene from other organisms that produce distinct forms of ubiquinone.
authors.affiliation: Department of Applied Bioscience and Biotechnology, Faculty of Life and Environmental Science, Shimane University, Matsue, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Okada
authors.forename: M
authors.initials: M
authors.lastname: Minehira
authors.forename: X
authors.initials: X
authors.lastname: Zhu
authors.forename: K
authors.initials: K
authors.lastname: Suzuki
authors.forename: T
authors.initials: T
authors.lastname: Nakagawa
authors.forename: H
authors.initials: H
authors.lastname: Matsuda
authors.forename: M
authors.initials: M
authors.lastname: Kawamukai
mesh_terms: D019883:Alkyl and Aryl Transferases; D000595:Amino Acid Sequence; D002876:Chromosomes, Bacterial; D000458:Cyanobacteria / Q000201:enzymology / Q000235:genetics; D004926:Escherichia coli / Q000201:enzymology* / Q000235:genetics* / Q000254:growth & development; D005798:Genes, Bacterial; D006193:Haemophilus influenzae / Q000201:enzymology / Q000235:genetics; D008969:Molecular Sequence Data; D016296:Mutagenesis; D010957:Plasmids; D017386:Sequence Homology, Amino Acid; D014166:Transferases / Q000096:biosynthesis / Q000737:chemistry / Q000235:genetics*; D014451:Ubiquinone / Q000378:metabolism
chemical_list: D014451:Ubiquinone; D014166:Transferases; D019883:Alkyl and Aryl Transferases; C048987:octaprenyl pyrophosphate synthetase