Unlabelled: Incomplete oxidation of glucose by sp. strain CHM43 produces gluconic acid and then 2- or 5-ketogluconic acid. Although 2-keto-D-gluconate (2KG) is a valuable compound, it is sometimes consumed by itself via an unknown metabolic pathway.
View Article and Find Full Text PDFBiosci Biotechnol Biochem
September 2022
3-Dehydroshikimate (3-DHS) is a key intermediate for the synthesis of various compounds, including the antiviral drug oseltamivir. The Gluconobacter oxydans strain NBRC3244 intrinsically oxidizes quinate to produce 3-dehydroquinate (3-DHQ) in the periplasmic space. Even though a considerable activity is detected in the recombinant G.
View Article and Find Full Text PDFsp. strain CHM43 oxidizes mannitol to fructose and then oxidizes fructose to 5-keto-d-fructose (5KF) in the periplasmic space. Since NADPH-dependent 5KF reductase was found in the soluble fraction of spp.
View Article and Find Full Text PDFWe characterized the pyrroloquinoline quinone (PQQ)-dependent dehydrogenase 9 (PQQ-DH9) of Gluconobacter sp. strain CHM43, which is a homolog of PQQ-dependent glycerol dehydrogenase (GLDH). We used a plasmid construct to express PQQ-DH9.
View Article and Find Full Text PDFDihydroxyacetone (DHA), a chemical suntan agent, is produced by the regiospecific oxidation of glycerol with Gluconobacter thailandicus NBRC3255. However, this microorganism consumes DHA produced in the culture medium. Here, we attempted to understand the pathway for DHA metabolism in NBRC3255 to minimize DHA degradation.
View Article and Find Full Text PDFBiosci Biotechnol Biochem
October 2020
Due to the indigestibility, utilization of konjac taro, has been limited only to the Japanese traditional konjac food. preparation with konjac taro was examined to utilize konjac taro as a source of utilizable carbohydrates. AKU 3302 was selected as a favorable strain for preparation, while used extensively in brewing industry was not so effective.
View Article and Find Full Text PDFBiosci Biotechnol Biochem
August 2020
CHM 43 have D-mannitol dehydrogenase (quinoprotein glycerol dehydrogenase) and flavoprotein D-fructose dehydrogenase in the membranes. When the two enzymes are functional, D-mannitol is converted to 5-keto-D-fructose with 65% yield when cultivated on D-mannitol. 5-Keto-D-fructose production with almost 100% yield was realized with the resting cells.
View Article and Find Full Text PDFMembrane-bound sorbosone dehydrogenase (SNDH) of Gluconacetobacter liquefaciens oxidizes l-sorbosone to 2-keto-l-gulonic acid (2KGLA), a key intermediate in vitamin C production. We constructed recombinant Escherichia coli and Gluconobacter strains harboring plasmids carrying the sndh gene from Ga. liquefaciens strain RCTMR10 to identify the prosthetic group of SNDH.
View Article and Find Full Text PDFMembrane-bound, pyrroloquinoline quinone (PQQ)-dependent glycerol dehydrogenase (GLDH, or polyol dehydrogenase) of Gluconobacter sp. oxidizes various secondary alcohols to produce the corresponding ketones, such as oxidation of D-sorbitol to L-sorbose in vitamin C production. Substrate specificity of GLDH is considered limited to secondary alcohols in the D-erythro configuration at the next to the last carbon.
View Article and Find Full Text PDFGluconobacter oxydans produces 3-dehydroquinate by oxidation of quinate through a reaction catalyzed by the quinate dehydrogenase (QDH), membrane-bound, pyrroloquinoline quinone (PQQ)-dependent dehydrogenase. We previously reported the nucleotide and deduced amino acid sequence of QDH and constructed a heterologous expression system of QDH in Pseudomonas sp. (A.
View Article and Find Full Text PDFA novel oxidation of D-pentonates to 4-keto-D-pentonates was analyzed with Gluconobacter thailandicus NBRC 3258. D-Pentonate 4-dehydrogenase activity in the membrane fraction was readily inactivated by EDTA and it was reactivated by the addition of PQQ and Ca. D-Pentonate 4-dehydrogenase was purified to two different subunits, 80 and 14 kDa.
View Article and Find Full Text PDFAcetic acid bacteria are gram-negative obligate aerobic bacteria assigned to the family Acetobacteraceae of Alphaproteobacteria. They are members of the genera Acetobacter, Gluconobacter, Gluconacetobacter, Acidomonas, Asaia, Kozakia, Swaminathania, Saccharibacter, Neoasaia, Granulibacter, Tanticharoenia, Ameyamaea, Neokomagataea, and Komagataeibacter. Many strains of Acetobacter and Komagataeibacter have been known to possess high acetic acid fermentation ability as well as the acetic acid and ethanol resistance, which are considered to be useful features for industrial production of acetic acid and vinegar, the commercial product.
View Article and Find Full Text PDFThe bacterial aerobic respiratory chain has a terminal oxidase of the heme-copper oxidase superfamily, comprised of cytochrome c oxidase (COX) and ubiquinol oxidase (UOX); UOX evolved from COX. Acetobacter pasteurianus, an α-Proteobacterial acetic acid bacterium (AAB), produces UOX but not COX, although it has a partial COX gene cluster, ctaBD and ctaA, in addition to the UOX operon cyaBACD. We expressed ctaB and ctaA genes of A.
View Article and Find Full Text PDFShikimate and 3-dehydroshikimate are useful chemical intermediates for the synthesis of various compounds, including the antiviral drug oseltamivir. Here, we show an almost stoichiometric biotransformation of quinate to 3-dehydroshikimate by an engineered Gluconobacter oxydans strain. Even under pH control, 3-dehydroshikimate was barely detected during the growth of the wild-type G.
View Article and Find Full Text PDFBiosci Biotechnol Biochem
December 2013
D-Ribose and 2-deoxy-D-ribose were oxidized to 4-keto-D-ribonate and 2-deoxy-4-keto-D-ribonate respectively by oxidative fermentation, and the chemical structures of the oxidation products were confirmed to be as expected. Both pentoses are important sugar components of nucleic acids. When examined, purine nucleosidase activity predominated in the membrane fraction of acetic acid bacteria.
View Article and Find Full Text PDFHere, we report the draft genome sequence of the acetic acid bacterium Glucnobacter thailandicus strain NBRC 3255. The draft genome sequence is composed of 109 contigs in 3,305,227 bp and contains 3,225 protein-coding genes. Two paralogous sets of sldAB operons, which are responsible for dihydroxyacetone production from glycerol, were identified.
View Article and Find Full Text PDFFurther upstream of sldSLC, genes for FAD-dependent D-sorbitol dehydrogenase in Gluconobacter frateurii, three additional genes (sldR, xdhA, and perA) are found: for a transcriptional regulator, NAD(P)-dependent xylitol dehydrogenase, and a transporter protein, a member of major facilitator superfamily, respectively. xdhA and perA but not sldR were found to be in the same transcriptional unit. Disruption of sldR resulted in a dramatic decrease in sldSLC promoter activity, indicating that it is an activator for sldSLC expression.
View Article and Find Full Text PDFWe succeeded in obtaining a strain adapted to higher temperature from a thermotolerant strain, Gluconobacter frateurii CHM43, for sorbose fermentation. The adapted strain showed higher growth and L-sorbose production than original CHM43 strain at higher temperature around 38.5-40 °C.
View Article and Find Full Text PDF4-Keto-D-arabonate (D-threo-pent-4-ulosonate) and 4-keto-D-ribonate (D-erythro-pent-4-ulosonate) were prepared from D-arabinose and D-ribose by two successive reactions of membrane-bound enzymes, D-aldopentose 4-dehydrogenase and 4-keto-D-aldopentose 1-dehydrogenase of Gluconobacter suboxydans IFO 12528. Alternatively, they were prepared from D-arabonate and D-ribonate with another membrane-bound enzyme, D-pentonate 4-dehydrogenase. Analytical data confirmed the chemical structures of the 4-pentulosonates prepared.
View Article and Find Full Text PDFAcetobacter tropicalis SKU1100 is a thermotolerant acetic acid bacterium that grows even at 42 °C, a much higher temperature than the limit for the growth of mesophilic strains. To elucidate the mechanism underlying the thermotolerance of this strain, we attempted to identify the genes essential for growth at high temperature by transposon (Tn10) mutagenesis followed by gene or genome analysis. Among the 4,000 Tn10-inserted mutants obtained, 32 exhibited a growth phenotype comparable to that of the parent strain at 30 °C but not at higher temperatures.
View Article and Find Full Text PDFIn our previous study, a new microbial reaction yielding 4-keto-D-arabonate from 2,5-diketo-D-gluconate was identified with Gluconacetobacter liquefaciens RCTMR 10. It appeared that decarboxylation and dehydrogenation took place together in the reaction. To analyze the nature of the reaction, investigations were done with the membrane fraction of the organism, and 4-keto-D-arabinose was confirmed as the direct precursor of 4-keto-D-arabonate.
View Article and Find Full Text PDFBiosci Biotechnol Biochem
August 2011
Selective, high-yield production of 5-keto-D-gluconate (5KGA) from D-glucose by Gluconobacter was achieved without genetic modification. 5KGA production by Gluconobacter suffers byproduct formation of 2-keto-D-gluconate (2KGA). By controlling the medium pH strictly in a range of pH 3.
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