title: A single membrane-bound enzyme catalyzes the conversion of 2,5-diketo-d-gluconate to 4-keto-d-arabonate in d-glucose oxidative fermentation by Gluconobacter oxydans NBRC 3292.
abstract: 4-Keto-d-arabonate synthase (4KAS), which converts 2,5-diketo-d-gluconate (DKGA) to 4-keto-d-arabonate (4KA) in d-glucose oxidative fermentation by some acetic acid bacteria, was solubilized from the Gluconobacter oxydans NBRC 3292 cytoplasmic membrane, and purified in an electrophoretically homogenous state. A single membrane-bound enzyme was found to catalyze the conversion from DKGA to 4KA. The 92-kDa 4KAS was a homodimeric protein not requiring O2 or a cofactor for the conversion, but was stimulated by Mn(2+). N-terminal amino acid sequencing of 4KAS, followed by gene homology search indicated a 1,197-bp open reading frame (ORF), corresponding to the GLS_c04240 locus, GenBank accession No. CP004373, encoding a 398-amino acid protein with a calculated molecular weight of 42,818 Da. An Escherichia coli transformant with the 4kas plasmid exhibited 4KAS activity. Furthermore, overexpressed recombinant 4KAS was purified in an electrophoretically homogenous state and had the same molecular size as the natural enzyme.
authors.affiliation: a Micology and Metabolic Diversity Research Center , Tamagawa University Research Institute , Machida , Japan.
authors.forename: Masaaki
authors.initials: M
authors.lastname: Tazoe
authors.affiliation: b Department of Life Science , Tamagawa University , Machida , Japan.
authors.forename: Hiromi
authors.initials: H
authors.lastname: Oishi
authors.affiliation: c HyphaGenesis Inc. , Machida , Japan.
authors.forename: Setsuko
authors.initials: S
authors.lastname: Kobayashi
authors.affiliation: a Micology and Metabolic Diversity Research Center , Tamagawa University Research Institute , Machida , Japan.
authors.forename: Tatsuo
authors.initials: T
authors.lastname: Hoshino
mesh_terms: D000595:Amino Acid Sequence; D001089:Arabinose / Q000031:analogs & derivatives / Q000378:metabolism*; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D002413:Cations, Divalent; D002462:Cell Membrane / Q000737:chemistry / Q000378:metabolism; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D005285:Fermentation; D015870:Gene Expression; D005942:Gluconates / Q000737:chemistry / Q000378:metabolism*; D020600:Gluconobacter oxydans / Q000201:enzymology* / Q000235:genetics; D005947:Glucose / Q000378:metabolism*; D008025:Ligases / Q000235:genetics / Q000378:metabolism*; D008345:Manganese / Q000737:chemistry / Q000378:metabolism; D008970:Molecular Weight; D016366:Open Reading Frames; D010084:Oxidation-Reduction; D010957:Plasmids / Q000737:chemistry / Q000378:metabolism; D011485:Protein Binding; D055503:Protein Multimerization; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid
chemical_list: D001426:Bacterial Proteins; D002413:Cations, Divalent; D005942:Gluconates; D011994:Recombinant Proteins; D008345:Manganese; C063875:2,5-diketogluconate; D001089:Arabinose; D008025:Ligases; D005947:Glucose
keywords: 2,5-diketo-d-gluconate; Gluconobacter oxydans; d-tartaric acid; membrane-bound 4-keto-d-arabonate synthase