title: A Glycopeptidyl-Glutamate Epimerase for Bacterial Peptidoglycan Biosynthesis.
abstract: d-Glutamate (Glu) supplied by Glu racemases or d-amino acid transaminase is utilized for peptidoglycan biosynthesis in microorganisms. Comparative genomics has shown that some microorganisms, including Xanthomonas oryzae, perhaps have no orthologues of these genes. We performed shotgun cloning experiments with a d-Glu auxotrophic Escherichia coli mutant as the host and X. oryzae as the DNA donor. We obtained complementary genes, XOO_1319 and XOO_1320, which are annotated as a hypothetical protein and MurD (UDP-MurNAc-l-Ala-d-Glu synthetase), respectively. By detailed in vitro analysis, we revealed that XOO_1320 is an enzyme to ligate l-Glu to UDP-MurNAc-l-Ala, providing the first example of MurD utilizing l-Glu, and that XOO_1319 is a novel enzyme catalyzing epimerization of the terminal l-Glu of the product in the presence of ATP and Mg2+. We investigated the occurrence of XOO_1319 orthologues and found that it exists in some categories of microorganisms, including pathogenic ones.
authors.affiliation: Graduate School of Chemical Sciences and Engineering, Hokkaido University , N13 & W8, Kita-ku, Sapporo, Hokkaido 060-8628, Japan.
authors.forename: Ruoyin
authors.initials: R
authors.lastname: Feng
authors.affiliation: Graduate School of Engineering, Hokkaido University , N13 & W8, Kita-ku, Sapporo, Hokkaido 060-8628, Japan.
authors.forename: Yasuharu
authors.identifier: 0000-0001-6671-7758
authors.initials: Y
authors.lastname: Satoh
authors.affiliation: Graduate School of Engineering, Hokkaido University , N13 & W8, Kita-ku, Sapporo, Hokkaido 060-8628, Japan.
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Ogasawara
authors.affiliation: Graduate School of Bioagricultural Sciences, Nagoya University , Furou-chou, Chikusa-ku, Nagoya, Aichi 464-8601, Japan.
authors.forename: Tohru
authors.initials: T
authors.lastname: Yoshimura
authors.affiliation: Graduate School of Engineering, Hokkaido University , N13 & W8, Kita-ku, Sapporo, Hokkaido 060-8628, Japan.
authors.forename: Tohru
authors.identifier: 0000-0002-3406-7970
authors.initials: T
authors.lastname: Dairi
mesh_terms: D020563:Gammaproteobacteria / Q000737:chemistry / Q000378:metabolism*; D018698:Glutamic Acid / Q000737:chemistry / Q000378:metabolism*; D006020:Glycopeptides / Q000737:chemistry / Q000378:metabolism*; D010457:Peptidoglycan / Q000096:biosynthesis* / Q000737:chemistry; D019998:Racemases and Epimerases / Q000378:metabolism*
chemical_list: D006020:Glycopeptides; D010457:Peptidoglycan; D018698:Glutamic Acid; D019998:Racemases and Epimerases