| coenzyme-induced slow transitions of nadp-sorbitol dehydrogenase from gluconobacter oxydans. | the kinetic properties of nadp-dependent sorbitol dehydrogenase from g. oxydans cell extract were studied at ph 8.8 and 9.3 in the direction of d-sorbitol oxydation. it was shown that the shape of the kinetic curves of nadph accumulation in time is characterised by initial burst whose magnitude depends on the concentration of the enzyme extract used. preincubation of the enzyme with nadp or d-sorbitol eliminated the initial burst on these curves and transformed them into straight lines coming fr ... | 1978 | 27247 |
| [efficiency of glucose utilization by gluconobacter oxydans]. | the dynamics of growth and acid production in gluconobacter oxydans cultures at various glucose concentrations has been investigated. dinitrophenol (10-4 m) was shown to have effect on hexonic acids formation by the growing culture and resting cells of g. oxydans, as well as on the values of y0. g. oxydans molar growth yield for glucose have been calculated. oxidative transformation of glucose was shown to be not involved in energy supply of processes connected with the reproduction of g. oxydan ... | 1979 | 470626 |
| lipid and fatty acid composition of gluconobacter oxydans before and after intracytoplasmic membrane formation. | gluconobacter oxydans differentiates by forming quantities of intracytoplasmic membranes at the end of exponential growth, and this formation occurs concurrently with a 60% increase in cellular lipid. the present study was initiated to determine whether this newly synthesized lipid differed from that extracted before intracytoplasmic membrane synthesis. undifferentiated exponential-phase cells were found to contain 30% phosphatidylcholine, 27.1% caridolipin, 25% phosphatidylethanolamine, 12.5% p ... | 1978 | 649571 |
| [effect of aeration on the biosynthesis of levansucrase by gluconobacter oxydans l-1]. | | 1978 | 724669 |
| myo-inositol dehydrogenase(s) from acetomonas oxydans. | experimental studies have been undertaken with a view of isolation of the enzyme(s) responsible for the stereospecific oxidation of myo-inositol. a partial fractionation has been achieved and the properties of this extract examined. results show that the active enzyme may well have a cytochrome component and there is indication that the stereospecificity of acetomonas oxydans results from permease as opposed to dehydrogenase activity. kinetic experiments suggest that only one type of active enzy ... | 1977 | 887081 |
| 5-deoxy-5-fluoro-l-sorbose originating from 2-deoxy-2-fluoro-d-glucitol by fermentation with acetomonas oxydans. | using fermentation with a selected strain of acetomonas oxydans it was possible to convert 2-deoxy-2-fluro-d-glucitol to 5-deoxy-5-fluoro-l-sorbose, in agreement with bertrand's and hudson's rule. the last-named compound was isolated in a yield of 88%. both compounds were little toxic against acetomonas oxydans. | 1977 | 892670 |
| biochemical dehydrogenations of saccharides. ix. d-lyxo-5-hexulosonic acid from d-mannose by acetomonas oxydans fermentation. | fermentation of nutrient media by a selected strain of acetomonas oxydans with a continuous ph control gave d-lyxo-5-hexulosonate in the form of a calcium or potassium salt with a yield equal to 95% of theory. the media contained up to 20 g d-mannose per 100 ml and a small amount of a readily assimilated monosaccharide. | 1977 | 924277 |
| [raffinose metabolism in gluconobacter oxydans]. | metabolism of raffinose has been examined in experiments with the growing culture and washed cells of gluconobacter oxydans l-1. degradtion of the trisaccharide was found to be catalyzed by levansucrase, levan being synthesized, and melibiose and small quantitites of fructose being liberated in the reaction. melibiose is not hydrolyzed and is not used by the bacterium as a source of carbon, but is oxidized to melibionic acid. fructose is assimilated by the bacterium in constructive metabolism, b ... | 1976 | 933868 |
| [effect on glucose on levansucrase synthesis by gluconobacter oxydans]. | the effect of glucose on synthesis of levansucrase was studied with gluconobacter oxydans l-1. glucose added to the nutritional medium containing sucrose was found to supress its degradation by g. oxydans l-1. at the same time, the lag phase became shorter. synthesis of levansucrase was inhibited in the nutritional medium containing glucose while the enzymatic activity increased proportionally to the amount of bacterial biomass in the medium containing sorbitol. addition of glucose to the nutrit ... | 1976 | 1032986 |
| intracytoplasmic membrane formation and increased oxidation of glycerol growth of gluconobacter oxydans. | gluconobacter oxydans is well known for the limited oxidation of compounds and rapid excretion of industrially important oxidation products. the dehydrogenases responsible for these oxidations are reportedly bound to the cell's plasma membrane. this report demonstrates that fully viable g. oxydans differentiates at the end of exponential growth by forming dense regions at the end of each cell observed with the light microscope. when these cells were thin sectioned, their polar regions contained ... | 1975 | 1158848 |
| change in quantity of lipids and cell size during intracytoplasmic membrane formation in gluconobacter oxydans. | electron microscopy previously revealed that gluconobacter oxydans differentiates by forming quantities of intracytoplasmic membranes at the end of exponential growth. it was also shown that the formation of these membranes appears concurrently with an increased rate of polyol oxidation. in the present study, exponential-phase cells devoid of intracytoplasmic membranes were harvested and the quantity of free lipid was determined. this quantity was compared with that extracted from cells harveste ... | 1976 | 1254552 |
| production of cephalexin by gluconobacter oxydans ccrc 10383. | intact cells of gluconobacter oxydans ccrc 10383 produced cephalexin from 7-amino-3-deacetoxy cephalosporanic acid (7-adca) and d-alpha-phenylglycine methylester hc1 (pgm). factors affecting the production of cephalexin by g. oxydans ccrc 10383 were studied. the optimum ph and temperature for the synthetic reaction of cephalexin were 6.0 and 42 degrees c, respectively. a higher concentration of pgm than 7-adca was required to obtain a good yield of cephalexin. | 1992 | 1305772 |
| mediated amperometric determination of xylose and glucose with an immobilized aldose dehydrogenase electrode. | an enzyme electrode was constructed for amperometric determination of xylose and glucose. the electrode is based on the pqq-dependent membrane-bound aldose dehydrogenase (aldh) from gluconobacter oxydans. aldh was covalently immobilized on a graphite electrode. immobilized dimethylferrocene, soluble ferrocene carboxylic acid and phenazine methosulphate were used as electron transfer mediators. when xylose was measured electrochemically using an electrode modified with aldh and dimethylferrocene, ... | 1992 | 1337972 |
| influence of constant and oscillating dissolved oxygen concentrations on keto acid production by gluconobacter oxydans subsps. melanogenum. | gluconobacter species are known to oxidise glucose via a direct oxidation pathway which is distinct from the pentose phosphate pathway. in the present communication results of an investigation on the influence of different dissolved oxygen concentrations (do) on the production of 2,5-diketogluconic acid in batch and chemostat cultures are given. do of 30% relative to air at 1 bar was found as a threshold level for optimum productivity. the positive influence of continuous availability of dissolv ... | 1992 | 1369152 |
| intergeneric protoplast fusion between gluconobacter oxydans and corynebacterium species. | intergeneric protoplast fusion between 2,5-diketo-gluconic acid producing gluconobacter oxydans (atcc 9937) and a mutant strain of corynebacterium species (atcc 31090), capable of reducing 2,5-diketo-gluconic acid to 2-keto-l-gulonic acid, a penultimate step in vitamin c production) resulted in viable recombinants. some of the fusion products exhibited the capacity to convert d-glucose to 2-keto-l-gulonic acid, but the conversion rate is low. | 1992 | 1369157 |
| a single amino acid substitution changes the substrate specificity of quinoprotein glucose dehydrogenase in gluconobacter oxydans. | gluconobacter oxydans contains pyrroloquinoline quinone-dependent glucose dehydrogenase (gdh). two isogenic g. oxydans strains, p1 and p2, which differ in their substrate specificity with respect to oxidation of sugars have been analysed. p1 can oxidize only d-glucose, whereas p2 is also capable of the oxidation of the disaccharide maltose. to investigate the nature of this maltose-oxidizing property we cloned the gene encoding gdh from p2. expression of p2 gdh in p1 enables the latter strain to ... | 1991 | 1833618 |
| a fast spheroplast formation procedure in some 2,5-diketo-d-gluconate- and 2-keto-l-gulonate- producing bacteria. | calcium 2-keto-l-gulonate (ca-2-klg, a key intermediate in vitamin c synthesis) is produced from calcium 2,5-diketo d-gluconate (ca-2,5-dkg) by a variety of bacteria. a few bacterial species which efficiently convert glucose to ca-2,5-dkg have been isolated in our laboratory. our bacterial collection included species that possess the genes for production of ca-2-klg from ca-2,5-dkg; however, the yield of the former is poor. a procedure for the preparation of spheroplasts in ca-2,5-dkg- and ca-2- ... | 1989 | 2517394 |
| the response of gluconobacter oxydans to sorbic and benzoic acids. | the minimal inhibitory concentrations (mic) of sorbic and benzoic acids for gluconobacter oxydans were 1000 mg/l and 900 mg/l respectively at ph 3.8. a reduction in the ph of the test medium to 3.3 reduced the mic of both preservatives by about 300 mg/l. when g. oxydans was grown in the presence of sublethal concentrations of sorbic or benzoic acids before the mic was determined, the mic of both compounds increased substantially within 1 h. growth of g. oxydans was modified in several ways by th ... | 1989 | 2641685 |
| purification and characterization of quinoprotein glucose dehydrogenase from acinetobacter calcoaceticus l.m.d. 79.41. | quinoprotein glucose dehydrogenase (ec 1.1.99.17) from acinetobacter calcoaceticus l.m.d. 79.41 was purified to homogeneity. it is a basic protein with an isoelectric point of 9.5 and an mr of 94,000. denaturation yields two molecules of pqq/molecule and a protein with an mr of 48000, indicating that the enzyme consists of two subunits, which are probably identical because even numbers of aromatic amino acids were found. the oxidized enzyme form has an absorption maximum at 350 nm, and the reduc ... | 1986 | 3800975 |
| myo-inositol dehydrogenase(s) from acetomonas oxydans. optimization of conditions for solubilization of membrane-bound enzyme. | methods are described for the first reported successful isolation of the soluble form of the membrane-bound myo-inositol dehydrogenase(s) from acetomonas oxydans. conditions for optimum yields of active enzyme in a crude membrane-free protein extract were established. the relevant conditions are (a) cell rupture by solid-shearing, (b) solubilization of the complete 60000g pellet with sodium deoxycholate at ph7.2, (c) rapid separation of the released protein from sodium deoxycholate by gel chroma ... | 1974 | 4214535 |
| [ethanol as source of energy but not of carbon in acetomonas oxydans]. | | 1967 | 5591329 |
| [utilization of ethanol by acetomonas oxydans]. | | 1968 | 5727910 |
| the oxidation of d-quinate and related acids by acetomonas oxydans. | 1. growing cells of a small number of strains of acetomonas oxydans oxidized d-quinate to 5-dehydroquinate. 2. d-shikimate was oxidized to 4,5-dihydroxy-3-oxocyclohex-1-ene-1-carboxylate (3-dehydroshikimate, formerly 5-dehydroshikimate). 3. d-dihydroshikimate was oxidized to the corresponding 5-dehydro compound, but epidihydroshikimate oxidation by growing cells was not observed. 4. cell-free extracts oxidized d-quinate to 5-dehydroquinate with the consumption of the stoicheiometric amount of ox ... | 1967 | 6030289 |
| [effect of cyclic adenosine-3',5'-monophosphate, chloramphenicol and actinomycin d on gluconobacter oxydans biosynthesis of extracellular levansaccharase]. | the biosynthesis of levansucrase by gluconobacter oxydans was shown to be induced in media containing sorbitol or fructose. an addition of glucose at a concentration of 0.1% to the culture growing in a medium with sorbitol stimulated the biosynthesis of levansucrase, whereas glucose at a concentration of 0.5-0.6% inhibited the enzyme synthesis by 20-30%. gluconic acid, a product of glucose metabolism, also repressed the synthesis of levansucrase, but to a lesser degree than glucose. cyclic adeno ... | 1982 | 6289057 |
| presence of a new cytochrome b - like pigment with a peak at 567 nm in various aerobic bacteria. | several physiological groups of bacteria were examined for the presence of a cytochrome b - like pigment which is demonstrable in dithionite-reduced minus substrate-reduced difference spectra. this pigment is characterized by an unusually high alpha band at 567 nm, a low concentration relative to conventional cytochromes, and an inability to be fully reduced by endogenous substrates or nadh. previous studies with one denitrifying and nondenitrifying species of the genus pseudomonas, in paracoccu ... | 1983 | 6652580 |
| [study of the pathways regulating the biosynthesis of gluconobacter oxydans levansucrase]. | the synthesis of levansucrase is derepressed during the growth of gluconobacter oxydans l-1 in media with mannitol, sorbitol or fructose. the level of levansucrase activity under these conditions is 20-30 times higher than in cultures growing in the presence of xylite, galactose or glucose. addition of mannitol or sucrose to the culture grown in a medium with xylite increases the differential rate of levansucrase synthesis. addition of glucose at a concentration of 1% to the culture growing in a ... | 1981 | 6783820 |
| effect of intracytoplasmic membrane development on oxidation of sorbitol and other polyols by gluconobacter oxydans. | by using membrane-bound dehydrogenases, gluconobacter oxydans characteristically accomplishes single-step oxidation of many polyols and quantitative release of the oxidation product into the medium. these cells typically differentiate by forming intracytoplasmic membranes (icm) after exponential growth on glycerol. earlier experiments demonstrated that glycerol-grown cells containing icm oxidized glycerol more rapidly than cells which were harvested during exponential growth and lacked icm (clau ... | 1982 | 7068538 |
| [purification and properties of levansucrase of gluconobacter oxydans l-1]. | levansucrase of g. oxydans l-1 which catalyzes the synthesis of the polysaccharide levan from the fructofuranosyl residues of sucrose has been isolated from the culture fluid and purified by chromatography on hydroxyapatite and gel-filtration on sephadex g-100. the molecular weight of levansucrase as measured by ds-na polyacrylamide gel electrophoresis is about 58000. the enzyme contains 25.86% of acidic amino acids, 13.74% of basic amino acids and 12.77% of aromatic amino acids. no cystine or c ... | 1980 | 7213834 |
| [role of the nutrient medium components in regulating levansaccharase synthesis in gluconobacter oxydans]. | the effect of phosphate and acetate buffer systems on the growth of gluconobacter oxydans and its synthesis of levansucrase was studied in nutrient media containing sorbitol. the intensification of constructive processes in media with an increased content of phosphate did not accelerate the enzyme biosynthesis by g. oxydans. as was shown in experiments with the intact cells of g. oxydans, the respiratory activity of the bacterium was stimulated in phosphate buffer supplemented with fructose. in ... | 1980 | 7402121 |
| nutritional requirements and biochemical activities of pineapple pink disease bacterial strains from hawaii. | bacteria which cause pink disease of pineapple, identified on the basis of their nutritional and biochemical activities, were found to belong to three genera. these bacteria include the following species: gluconobacter oxydans, acetobacter aceti, and erwinia herbicola. several pink disease strains required one to three vitamins for growth. both g. oxydans strains 303d and 180 required biotin, nicotinic acid, and pantothenic acid for growth; e. herbicola 189 required only nicotinic acid; however, ... | 1980 | 7436404 |
| cloning and nucleotide sequencing of the membrane-bound l-sorbosone dehydrogenase gene of acetobacter liquefaciens ifo 12258 and its expression in gluconobacter oxydans. | cloning and expression of the gene encoding acetobacter liquefaciens ifo 12258 membrane-bound l-sorbosone dehydrogenase (sndh) were studied. a genomic library of a. liquefaciens ifo 12258 was constructed with the mobilizable cosmid vector pvk102 (mob+) in escherichia coli s17-1 (tra+). the library was transferred by conjugal mating into gluconobacter oxydans ox4, a mutant of g. oxydans ifo 3293 that accumulates l-sorbosone in the presence of l-sorbose. the transconjugants were screened for sndh ... | 1995 | 7574579 |
| biochemical characterization and sequence analysis of the gluconate:nadp 5-oxidoreductase gene from gluconobacter oxydans. | gluconate:nadp 5-oxidoreductase (gno) from the acetic acid bacterium gluconobacter oxydans subsp. oxydans dsm3503 was purified to homogeneity. this enzyme is involved in the nonphosphorylative, ketogenic oxidation of glucose and oxidizes gluconate to 5-ketogluconate. gno was localized in the cytoplasm, had an isoelectric point of 4.3, and showed an apparent molecular weight of 75,000. in sodium dodecyl sulfate gel electrophoresis, a single band appeared corresponding to a molecular weight of 33, ... | 1995 | 7751271 |
| large-scale applicable purification and characterization of a membrane-bound pqq-dependent aldose dehydrogenase. | a membrane-bound xylose oxidizing pqq-dependent dehydrogenase from gluconobacter oxydans was purified with a simple large-scale applicable purification procedure. the activity recovery from membrane extract was 33% with 130-fold purification. important characteristic with respect to the application of the dehydrogenase in biosensor technology were studied. the purified enzyme was most stable in the ph range 3.5-6.5. the ph optimum for xylose oxidation was in the range 7.5-8 for the solubilized e ... | 1993 | 7763900 |
| characterisation of plasmids from diketogluconic acid producing strains of gluconobacter oxydans. | gluconobacter oxydans atcc 9937, which produces 2,5-diketogluconic acid, an intermediate in vitamin c synthesis, has three plasmids of sizes 27.7 kb (pvj1), 12.3 kb (pvj2) and 18 kb (pvj4). a restriction map was constructed of pvj1. a potential glucose dehydrogenase gene was located on pvj1 using the polymerase chain reaction with heterologous primers. two other g. oxydans strains had no detectable plasmid dna (ifo 12258) and a plasmid (pvj3) of 9.4 kb (ifo 3293), respectively. | 1994 | 7765162 |
| [biosensor models based on potentiometric and amperometric transducers for use in medicine, biotechnology, and environmental monitoring (review)]. | various types of potentiometric and amperometric biosensors are characterized: microbial sensors with gluconobacter oxydans cells with potentiometric (ph-sensitive field-effect transistor) and amperometric (clark-type) electrodes for determining glucose; a potentiometric enzymatic electrode with butyrylcholinesterase, which is used in the biosensor designed to detect pesticides; immunosensors with ph-sensitive field-effect transistors which detect the herbicide 2, 4-d; a biosensor for human immu ... | 1996 | 8637842 |
| [sensor for rapid measurement of blood glucose]. | bacterial biosensor consisting of gluconobacter oxydans cells immobilized on the surface of oxygen electrode was used for measuring glucose concentration in human blood serum. the results were compared with those of standard clinical method (color reaction with ortho-toluidine). the proposed biosensor permits highly accurate measurements (mean quadratic deviation no more than 2% of the mean arithmetic), the coefficient of correlation with the results of standard method being 0.970. | 1996 | 8680764 |
| fet-microbial sensor for xylose detection based on gluconobacter oxydans cells. | a potentiometric biosensor for xylose was devised utilizing gluconobacter oxydans whole cells. immobilization methods based on physical adsorption were used for g. oxydans cells and extracellular ph changes resulting from xylose dehydrogenation were monitored by a field effect transistor (fet). the g. oxydans, fet-based sensor detected xylose at a lower limit of 0.5 mm. from 5.0 to 30 mm xylose, the response of the sensor was linear. expectedly, output signals were significantly suppressed by bu ... | 1996 | 8746186 |
| identification and characterization of a pantoea citrea gene encoding glucose dehydrogenase that is essential for causing pink disease of pineapple. | pantoea citrea, a member of the family enterobacteriaceae, causes pink disease of pineapple, whose symptom is characterized by the formation of pink to brown discolorations of the infected portions of the pineapple fruit cylinder upon canning. molecular genetic approaches were applied to elucidate the mechanism responsible for this fruit discoloration. a p. citrea mutant strain, cmc6, defective in its ability to cause pink disease and fruit discoloration, was generated by nitrosoguanidine mutage ... | 1997 | 8979341 |
| cloning of genes coding for l-sorbose and l-sorbosone dehydrogenases from gluconobacter oxydans and microbial production of 2-keto-l-gulonate, a precursor of l-ascorbic acid, in a recombinant g. oxydans strain. | we have purified l-sorbose dehydrogenase (sdh) and l-sorbosone dehydrogenase (sndh) from gluconobacter oxydans t-100 that showed an ability to convert d-sorbitol to 2-keto-l-gulonate (2-klga). a genomic library of gluconobacter oxydans t-100 was screened with a probe, a 180-bp pcr product which was obtained from degenerate oligodeoxyribonucleotides based on the elucidated sequence of the purified sdh (used as primers) and the genomic dna of g. oxydans t-100 (used as a template). from sequencing ... | 1997 | 9023923 |
| transposon induced mutation in gluconobacter oxydans with special reference to its direct-glucose oxidation metabolism. | transposons are important genetic tools for mutation studies and for location of genes in prokaryotes. however, very little published work is available on transposon mutagenesis in gluconobacter oxydans. we report here tn5-induced mutation in a keto acid-producing strain of g. oxydans atcc 9937 with special reference to the direct-glucose oxidation pathway operative in this organism. in this study, a mutant deficient in glucose dehydrogenase (gdh) activity has been developed by tn5 mutagenesis. ... | 1997 | 9119191 |
| the phylogeny of acetic acid bacteria based on the partial sequences of 16s ribosomal rna: the elevation of the subgenus gluconoacetobacter to the generic level. | thirty-six strains of acetic acid bacteria classified in the genera acetobacter, gluconobacter, and acidomonas were examined for their partial base sequences in positions 1220 through 1375, 156 bases, of 16s rrna. the strains of the q10-equipped gluconobacter species examined were divided into two subgroups, which included the type strains of gluconobacter oxydans, the type species of the genus gluconobacter, and of a second species, gluconobacter cerinus, respectively. the base differences numb ... | 1997 | 9301103 |
| biotransformation in organic media by enzymes and whole cells. | biotransformation of poorly water soluble compounds in organic media by immobilized enzyme and whole cells is illustrated in this paper taking the following examples from the author's laboratory: (1) controlled hydrolysis of triglycerides and synthesis reactions by a recombinant lipolytic enzyme (cutinase); (2) enzymatic synthesis of dipeptides; (3) continuous production of isovaleraldehyde by gluconobacter oxydans in isooctane; and (4) sitosterol side chain cleavage by mycobacterium sp. the rol ... | 1997 | 9487721 |
| molecular characterization of gluconobacter oxydans reca gene and its inhibitory effect on the function of the host wild-type reca gene. | a dna fragment containing the reca gene of gluconobacter oxydans was isolated and further characterized for its nucleotide sequence and ability to functionally complement various reca mutations. when expressed in an escherichia coli reca host, the g. oxydans reca protein could efficiently function in homologous recombination and dna damage repair. the reca gene's nucleotide sequence analysis revealed a protein of 344 amino acids with a molecular mass of 38 kda. we observed an e. coli-like lexa r ... | 1998 | 9543716 |
| cocoa fermentations conducted with a defined microbial cocktail inoculum. | cocoa fermentations were performed in wooden boxes under the following four experimental regimens: beans naturally fermented with wild microflora; aseptically prepared beans with no inoculum; and beans inoculated with a defined cocktail containing microorganisms at a suitable concentration either at zero time or by using phased additions at appropriate times. the cocktail used consisted of a yeast, saccharomyces cerevisiae var. chevalieri, two lactic acid bacterial species, lactobacillus lactis ... | 1998 | 9546184 |
| [electrocatalytic oxidation of substrates by immobilized gluconobacter oxydans cells in the presence of an electron transport mediator]. | | 1998 | 9551324 |
| microbial cell-based biosensor for sensing glucose, sucrose or lactose. | biosensors for the determination of glucose, sucrose and lactose were based on a clark-type oxygen electrode covered with a membrane containing microbial cells. the glucose-sensing membrane was prepared with intact cells of gluconobacter oxydans immobilized in gelatin cross-linked with glutardialdehyde. the disaccharide-sensing membranes were prepared by co-immobilization of g. oxydans with cells of saccharomyces cerevisiae containing invertase for sucrose determination and with permeabilized ce ... | 1998 | 9569611 |
| what's for dinner?: entner-doudoroff metabolism in escherichia coli. | | 1998 | 9657988 |
| sequence analysis of the gntii (subsidiary) system for gluconate metabolism reveals a novel pathway for l-idonic acid catabolism in escherichia coli. | the presence of two systems in escherichia coli for gluconate transport and phosphorylation is puzzling. the main system, gnti, is well characterized, while the subsidiary system, gntii, is poorly understood. genomic sequence analysis of the region known to contain genes of the gntii system led to a hypothesis which was tested biochemically and confirmed: the gntii system encodes a pathway for catabolism of l-idonic acid in which d-gluconate is an intermediate. the genes have been named accordin ... | 1998 | 9658018 |
| [physiologo-biochemical characteristics if gluconobacter oxydans and prospects for its use in biotechnology and biosensor systems (review)]. | gluconobacter oxydans possesses a unique organization of metabolic systems, which are characterized by reduction of major dissimilation pathways, surface localization of main oxidative enzymes responsible for partial oxidation of carbon substrates, high performance of electron-transport chains, and accumulation of partially oxidized metabolites in the medium. these features allow us to use the cells of these microorganisms in biotechnology for production of several food products and medicines. t ... | 1998 | 9749431 |
| [membrane-bound dehydrogenases of gluconobacter oxydans whole cells as basis for sensors for determination of sugars, alcohols, and polyols]. | | 1998 | 9777202 |
| the yiae gene, located at 80.1 minutes on the escherichia coli chromosome, encodes a 2-ketoaldonate reductase. | an open reading frame located in the bisc-cspa intergenic region, or at 80.1 min on the escherichia coli chromosome, encodes a hypothetical 2-hydroxyacid dehydrogenase, which was identified as a result of the e. coli genome sequencing project. we report here that the product of the gene (yiae) is a 2-ketoaldonate reductase (2kr). the gene was cloned and expressed with a c-terminal his tag in e. coli, and the protein was purified by metal-chelate affinity chromatography. the determination of the ... | 1998 | 9811658 |
| detection of ethanol in a two-component glucose/ethanol mixture using a nonselective microbial sensor and a glucose enzyme electrode. | chemometric theory was applied to a microbial sensor for determinations of ethanol in the presence of glucose. microbial sensors, consisting of gluconobacter oxydans cells immobilized on clark-type amperometric oxygen electrodes, exhibited good sensitivity but low selectivity toward ethanol and glucose. an eksan-g commercial glucose analyzer was used as a second sensor for multivariate calibration and analyses. microbial sensors exhibited nearly complete additivity for total glucose plus ethanol ... | 1998 | 9828373 |
| effects of high oxygen concentrations on microbial biosensor signals. hyperoxygenation by means of perfluorodecalin. | amperometric biosensors register oxygen depletion in response to analyte catabolism, and thus are limited by the availability of dissolved oxygen. microbial sensors containing immobilized cells of gluconobacter oxydans were hyperoxygenated to 400% of control levels and the effects on sensor responses to glucose were determined. oxygenated perfluorodecalin (a completely fluorinated organic substance) was as effective in hyperoxygenation as direct sparging with o2, increasing sensor base medium ox ... | 1998 | 9828374 |
| poly-3-hydroxybutyrate degradation in rhizobium (sinorhizobium) meliloti: isolation and characterization of a gene encoding 3-hydroxybutyrate dehydrogenase. | we have cloned and sequenced the 3-hydroxybutyrate dehydrogenase-encoding gene (bdha) from rhizobium (sinorhizobium) meliloti. the gene has an open reading frame of 777 bp that encodes a polypeptide of 258 amino acid residues (molecular weight 27,177, pi 6.07). the r. meliloti bdh protein exhibits features common to members of the short-chain alcohol dehydrogenase superfamily. bdha is the first gene transcribed in an operon that also includes xdha, encoding xanthine oxidase/dehydrogenase. transc ... | 1999 | 9922248 |
| direct fermentation of 2-keto-l-gulonic acid in recombinant gluconobacter oxydans. | we isolated gluconobacter oxydans t-100 that had an activity to produce 2-klga from d-sorbitol; however, the yield of 2-klga was quite insufficient. therefore, enzymes involved in the biosynthesis of l-sorbosone and 2-klga, l-sorbose dehydrogenase (sdh) and l-sorbosone dehydrogenase (sndh), respectively, were purified from g. oxydans t-100. a genomic library of g. oxydans t-100 was screened to clone both genes for sdh and sndh based on their amino acid sequences. sndh and sdh were encoded in seq ... | 1998 | 10191408 |
| sequence analysis of the gluconobacter oxydans reca protein and construction of a reca-deficient mutant. | the deduced amino acid sequence of gluconobacter oxydans reca protein shows 75.2, 69.4, and 66.2% homology with those from aquaspirillum magnetotacticum, escherichia coli, and pseudomonas aeruginosa, respectively. the amino acid residues essential for function of the recombinase, protease, and atpase in e. coli reca protein are conserved in g. oxydans. of 24 amino acid residues believed to be the atp binding domain of e. coli reca, 17 are found to be identical in g. oxydans reca. interestingly, ... | 1999 | 10420585 |
| identification of the yqhe and yafb genes encoding two 2, 5-diketo-d-gluconate reductases in escherichia coli. | the identification of a gene (yiae) encoding 2-ketoaldonate reductase (2kr) in our previous work led to the hypothesis that escherichia coli has other ketogluconate reductases including 2, 5-diketo-d-gluconate reductase (25dkgr) and to study of the related ketogluconate metabolism. by using the deduced amino acid sequences of 5-diketo-d-gluconate reductase (5kdgr) of gluconobacter oxydans and 25dkgr of corynebacterium sp., protein databases were screened to detect homologous proteins. among the ... | 1999 | 10427017 |
| community analysis of biofilters using fluorescence in situ hybridization including a new probe for the xanthomonas branch of the class proteobacteria. | domain-, class-, and subclass-specific rrna-targeted probes were applied to investigate the microbial communities of three industrial and three laboratory-scale biofilters. the set of probes also included a new probe (named xan818) specific for the xanthomonas branch of the class proteobacteria; this probe is described in this study. the members of the xanthomonas branch do not hybridize with previously developed rrna-targeted oligonucleotide probes for the alpha-, beta-, and gamma-proteobacteri ... | 1999 | 10427047 |
| a mutant of gluconobacter oxydans deficient in gluconic acid dehydrogenase | gluconobacter oxydans atcc 9937 was subjected to transposon mutagenesis using tn5. a non-pigmented mutant was shown to be defective in gluconic acid dehydrogenase and to produce gluconic acid from glucose, whereas the parent strain produced 2, 5-diketogluconic acid. cloning and sequencing of the region containing the tn5 insertion showed that the insertion point occurred in an open reading frame homologous (42% amino acid identity) to the ribf genes of pseudomonas fluorescens and escherichia col ... | 1999 | 10518757 |
| methanotroph diversity in landfill soil: isolation of novel type i and type ii methanotrophs whose presence was suggested by culture-independent 16s ribosomal dna analysis. | the diversity of the methanotrophic community in mildly acidic landfill cover soil was assessed by three methods: two culture-independent molecular approaches and a traditional culture-based approach. for the first of the molecular studies, two primer pairs specific for the 16s rrna gene of validly published type i (including the former type x) and type ii methanotrophs were identified and tested. these primers were used to amplify directly extracted soil dna, and the products were used to const ... | 1999 | 10543800 |
| a study of dextran production from maltodextrin by cell suspensions of gluconobacter oxydans ncib 4943. | this study investigated dextran synthesis from a commercial maltodextrin substrate using cell suspensions of g. oxydans ncib 4943 as catalysts. experiments were arranged according to a central composite statistical design. the effects of substrate concentration (10-100 g l-1), cell concentration (0.32-32.0 g wet weight l-1), time of reaction (8-48 h) and ph (3.5-5.5), each at three levels, on dextran yield and dextran molecular weight (mw), were investigated. response surface methodology was use ... | 1999 | 10583683 |
| genetic and biochemical characterization of the pathway in pantoea citrea leading to pink disease of pineapple. | pink disease of pineapple, caused by pantoea citrea, is characterized by a dark coloration on fruit slices after autoclaving. this coloration is initiated by the oxidation of glucose to gluconate, which is followed by further oxidation of gluconate to as yet unknown chromogenic compounds. to elucidate the biochemical pathway leading to pink disease, we generated six coloration-defective mutants of p. citrea that were still able to oxidize glucose into gluconate. three mutants were found to be af ... | 2000 | 10735866 |
| cloning and expression of ntnd, encoding a novel nad(p)(+)-independent 4-nitrobenzyl alcohol dehydrogenase from pseudomonas sp. strain tw3. | pseudomonas sp. strain tw3 is able to metabolize 4-nitrotoluene to 4-nitrobenzoate and toluene to benzoate aerobically via a route analogous to the upper pathway of the tol plasmids. we report the cloning and characterization of a benzyl alcohol dehydrogenase gene (ntnd) which encodes the enzyme for the catabolism of 4-nitrobenzyl alcohol and benzyl alcohol to 4-nitrobenzaldehyde and benzaldehyde, respectively. the gene is located downstream of the previously reported ntn gene cluster. ntnd bear ... | 2000 | 10809692 |
| optimized synthesis of l-sorbose by c(5)-dehydrogenation of d-sorbitol with gluconobacter oxydans. | the optimization of l-sorbose synthesis by regiospecific dehydrogenation of d-sorbitol using gluconobacter oxydans is reported. the current l-sorbose production processes that are based on g. oxydans and other bacterial strains are suboptimal as to yield and rate of l-sorbose synthesis. one reason for these problems is the toxicity that is induced by the substrate d-sorbitol when used in concentrations of >10% (w/v). this phenomenon significantly limits the potentials of l-sorbose production fro ... | 2000 | 10861414 |
| bacteria in the leaf ecosystem with emphasis on pseudomonas syringae-a pathogen, ice nucleus, and epiphyte. | the extremely large number of leaves produced by terrestrial and aquatic plants provide habitats for colonization by a diversity of microorganisms. this review focuses on the bacterial component of leaf microbial communities, with emphasis on pseudomonas syringae-a species that participates in leaf ecosystems as a pathogen, ice nucleus, and epiphyte. among the diversity of bacteria that colonize leaves, none has received wider attention than p. syringae, as it gained notoriety for being the firs ... | 2000 | 10974129 |
| the pyrroloquinoline quinone synthesis genes of gluconobacter oxydans. | a tn5-induced glucose dehydrogenase (gdh) deficient mutant of gluconobacter oxydans ifo 3293 was characterised. dna sequencing showed that the insertion site occurred in an open reading frame with homology to the pqqe gene. it was shown that acid production could be restored by addition of the coenzyme pyrroloquinoline quinone (pqq) to the medium. the pqq cluster of g. oxydans atcc 9937 was cloned and sequenced. it has five genes pqqa-e. the cluster could complement the tn5-induced mutation in i ... | 2000 | 11111029 |
| monitoring of dihydroxyacetone production during oxidation of glycerol by immobilized gluconobacter oxydans cells with an enzyme biosensor. | a bi-enzymatic biosensor for monitoring of dihydroxyacetone production during oxidation of glycerol by bacterial cells of gluconobacter oxydans is presented. galactose oxidase oxidizes dihydroxyacetone efficiently producing hydrogen peroxide, which reacts with co-immobilized peroxidase and ferrocene pre-adsorbed on graphite electrode. this mediator-based bi-enzymatic biosensor possesses very high sensitivity (4.7 µa/mm in phosphate buffer), low detection limit (0.8 µm, signal/noise = 3), short r ... | 2001 | 11240195 |
| cloning and expression of glucose 3-dehydrogenase from halomonas sp. alpha-15 in escherichia coli. | the gene encoding glucose 3-dehydrogenase (g3dh) from halomonas sp. alpha-15 was cloned and expressed in escherichia coli. an open reading frame of 1686 nucleotides was shown to encode g3dh. the flavine adenine dinucleotide binding motif was found in the n-terminal region of g3dh. the deduced primary structure of g3dh showed about 30% identity to sorbitol dehydrogenase from gluconobacter oxydans and 2-keto-d-gluconate dehydrogenases from erwinia herbicola and pantoea citrea. the folding predicti ... | 2001 | 11263965 |
| gluconobacter oxydans: its biotechnological applications. | gluconobacter oxydans is a gram-negative bacterium belonging to the family acetobacteraceae. g. oxydans is an obligate aerobe, having a respiratory type of metabolism using oxygen as the terminal electron acceptor. gluconobacter strains flourish in sugary niches e.g. ripe grapes, apples, dates, garden soil, baker's soil, honeybees, fruit, cider, beer, wine. gluconobacter strains are non-pathogenic towards man and other animals but are capable of causing bacterial rot of apples and pears accompan ... | 2001 | 11361077 |
| taxonomic characterization of ketogulonigenium vulgare gen. nov., sp. nov. and ketogulonigenium robustum sp. nov., which oxidize l-sorbose to 2-keto-l-gulonic acid. | four bacterial strains that oxidize l-sorbose to 2-keto-l-gulonic acid, a key intermediate in the synthesis of vitamin c, were isolated from soils of geographically distinct locations. all were gram-negative, facultatively anaerobic, chemoheterotrophic rods. comparative analysis revealed nearly identical 16s rdna sequences amongst them (99.7-100% identical) and identified them as members of the alpha-subclass of the proteobacteria. phylogenetic analysis identified the closest taxonomically defin ... | 2001 | 11411674 |
| modelling bacterial spoilage in cold-filled ready to drink beverages by acinetobacter calcoaceticus and gluconobacter oxydans. | mathematical models were created which predict the growth of spoilage bacteria in response to various preservation systems. | 2001 | 11473588 |
| substrate selectivity of gluconobacter oxydans for production of 2,5-diketo-d-gluconic acid and synthesis of 2-keto-l-gulonic acid in a multienzyme system. | substrate selectivity of gluconobacter oxydans (atcc 9937) for 2,5-diketo-d-gluconic acid (2,5-dkg) production was investigated with glucose, gluconic acid, and gluconolactone in different concentrations using a resting-cell system. the results show that gluconic acid was utilized favorably by g. oxydans as substrate to produce 2,5-dkg. the strain was coupled with glucose dehydrogenase (gdh) and 2,5-dkg reductase for synthesis of 2-keto-l-gulonic acid (2-klg), a direct precursor of l-ascorbic ac ... | 2001 | 11563824 |
| the first step in polyethylene glycol degradation by sphingomonads proceeds via a flavoprotein alcohol dehydrogenase containing flavin adenine dinucleotide. | several sphingomonas spp. utilize polyethylene glycols (pegs) as a sole carbon and energy source, oxidative peg degradation being initiated by a dye-linked dehydrogenase (peg-dh) that oxidizes the terminal alcohol groups of the polymer chain. purification and characterization of peg-dh from sphingomonas terrae revealed that the enzyme is membrane bound. the gene encoding this enzyme (pega) was cloned, sequenced, and expressed in escherichia coli. the purified recombinant enzyme was vulnerable to ... | 2001 | 11673442 |
| analysis of ethanol-glucose mixtures by two microbial sensors: application of chemometrics and artificial neural networks for data processing. | although biosensors based on whole microbial cells have many advantages in terms of convenience, cost and durability, a major limitation of these sensors is often their inability to distinguish between different substrates of interest. this paper demonstrates that it is possible to use sensors entirely based upon whole microbial cells to selectively measure ethanol and glucose in mixtures. amperometric sensors were constructed using immobilized cells of either gluconobacter oxydans or pichia met ... | 2001 | 11679281 |
| [effect of bacillus megaterium on gluconobacter oxydans in mixed culture]. | to reveal the relationship between bacillus megaterium and gluconobacter oxydans in the mixed culture of vitamin c two-step fermentation, the effect of b. megaterium on the growth of g. oxydans and its synthesizing ability of 2-keto-l-gulonic acid(2kga) was studied. the bioactive metabolites which could enhance the synthesis of 2kga were isolated and purified by ultrafiltration, gel chromatography and sds-polyacrylamide gel electrophoresis. both the culture supernatant and the cytosol of b. mega ... | 2000 | 11766567 |
| novel medium-chain prenyl diphosphate synthase from the thermoacidophilic archaeon sulfolobus solfataricus. | two open reading frames which encode the homologues of (all-e) prenyl diphosphate synthase are found in the whole-genome sequence of sulfolobus solfataricus, a thermoacidophilic archaeon. it has been suggested that one is a geranylgeranyl diphosphate synthase gene, but the specificity and biological significance of the enzyme encoded by the other have remained unclear. thus, we isolated the latter by the pcr method, expressed the enzyme in escherichia coli cells, purified it, and characterized i ... | 2002 | 11790729 |
| nadph-dependent l-sorbose reductase is responsible for l-sorbose assimilation in gluconobacter suboxydans ifo 3291. | the nadph-dependent l-sorbose reductase (sr) of l-sorbose-producing gluconobacter suboxydans ifo 3291 contributes to intracellular l-sorbose assimilation. the gene disruptant showed no sr activity and did not assimilate the once-produced l-sorbose, indicating that the sr functions mainly as an l-sorbose-reducing enzyme in vivo and not as a d-sorbitol-oxidizing enzyme. | 2002 | 11790761 |
| the enumeration and identification of acetic acid bacteria from south african red wine fermentations. | acetic acid bacteria are microorganisms that can profoundly influence the quality of wine. surprisingly, little research has been done on these microorganisms in the winemaking field. the object of this study was to investigate the occurrence of acetic acid bacteria in south african red wine fermentations and to identify the dominant species occurring. acetic acid bacteria were isolated and enumerated from small-scale and commercial red must fermentations in 1998 and 1999, respectively. the init ... | 2002 | 11930953 |
| cloning of escherichia coli lacz and lacy genes and their expression in gluconobacter oxydans and acetobacter liquefaciens. | an efficient transformation protocol for gluconobacter oxydans and acetobacter liquefaciens strains was developed by preparation of electrocompetent cells grown on yeast extract-ethanol medium. plasmid pbbr122 was used as broad-host-range vector to clone the escherichia coli laczy genes in g. oxydans and a. liquefaciens. although both lac genes were functionally expressed in both acetic acid bacteria, only a few transformants were able to grow on lactose. however, this ability strictly depended ... | 2002 | 11976147 |
| molecular cloning and functional expression of d-sorbitol dehydrogenase from gluconobacter suboxydans if03255, which requires pyrroloquinoline quinone and hydrophobic protein sldb for activity development in e. coli. | the slda gene that encodes the d-sorbitol dehydrogenase (sldh) from gluconobacter suboxydans ifo 3255 was cloned and sequenced. it encodes a polypeptide of 740 residues, which contains a signal sequence of 24 residues. sldh had 35-37% identity to the membrane-bound quinoprotein glucose dehydrogenases (gdhs) from e. coli, gluconobacter oxydans, and acinetobacter calcoaceticus except the n-terminal hydrophobic region of gdh. additionally, the sldb gene located just upstream of slda was found to en ... | 2002 | 11999397 |
| monitoring of ethanol during fermentation using a microbial biosensor with enhanced selectivity. | the present study is concerning the construction of ferricyanide-mediated gluconobacter oxydans cell ethanol biosensor. the size exclusion effect of a cellulose acetate membrane was used for elimination of glucose interferences during ethanol assays in real samples. a typical response time of the biosensor was 13 s with a high sensitivity of 3.5 microa mm(-1). the microbial biosensor exhibits a very low detection limit of 0.85 microm and a wide linear range from 2 to 270 microm. the operational ... | 2002 | 12009458 |
| kozakia baliensis gen. nov., sp. nov., a novel acetic acid bacterium in the alpha-proteobacteria. | four bacterial strains were isolated from palm brown sugar and ragi collected in bali and yogyakarta, indonesia, by an enrichment culture approach for acetic acid bacteria. phylogenetic analysis based on 16s rrna gene sequences showed that the four isolates constituted a cluster separate from the genera acetobacter, gluconobacter, acidomonas, gluconacetobacter and asaia with a high bootstrap value in a phylogenetic tree. the isolates had high values of dna-dna similarity (78-100%) between one an ... | 2002 | 12054243 |
| effect of initial carbon sources on the electrochemical detection of glucose by gluconobacter oxydans. | an electrochemical system consisted of gluconobacter oxydans as a microorganism and 2-hydroxy-1,4-naphthoquinone (hnq) as a mediator has been setup to examine the effect of initial carbon sources on the detection of glucose. catalytic current due to the oxidation of glucose was observed only when both g. oxydans and hnq were present. from amperometric measurements, it was found that the sensitivity strongly depended on the initial carbon sources. the sensitivity was highest for the cells culture ... | 2002 | 12160615 |
| gluconobacter asaii mason and claus 1989 is a junior subjective synonym of gluconobacter cerinus yamada and akita 1984. | five strains received as gluconobacter cerinus and gluconobacter asaii were examined for dna base composition, dna-dna similarity, 16s rrna gene sequences and phenotypic characteristics, including acid production from ethanol, growth on l-arabitol and meso-ribitol and requirement for nicotinic acid. the five strains showed dna base compositions ranging from 54 to 56 mol% g+c. g. cerinus ifo 3267t and iam 1832 and g. asaii ifo 3276t and ifo 3275 showed high levels of dna-dna similarity (70-100%) ... | 2002 | 12361267 |
| continuous production of high-content fructooligosaccharides by a complex cell system. | a complex biocatalyst system with a bioreactor equipped with a microfiltration (mf) module was employed to produce high-content fructooligosaccharides (fos) in a continuous process initiated by a batch process. the system used mycelia of aspergillus japonicus ccrc 93007 or aureobasidium pullulans atcc 9348 with beta-fructofuranosidase activity and gluconobacter oxydans atcc 23771 with glucose dehydrogenase activity. calcium carbonate slurry was used to control ph to 5.5, and gluconic acid in the ... | 2002 | 12467463 |
| identification of acetic acid bacteria isolated from indonesian sources, especially of isolates classified in the genus gluconobacter. | sixty-four strains of acetic acid bacteria were isolated from indonesian sources such as fruits, flowers, and fermented foods by the enrichment culture at ph 3.5. forty-five strains were routinely identified as acetobacter strains because of their oxidation of acetate and lactate to carbon dioxide and water and their q-9 isoprenolog, corresponding to 70% of all the 64 acetic acid bacteria isolated. eight isolates were identified as gluconacetobacter strains because of their oxidation of acetate ... | 1999 | 12501398 |
| relationship between intra- and extracellular dextran dextrinase from gluconobacter oxydans atcc 11894. | | 2002 | 12510585 |
| [determination of chromosome of gluconobacter oxydans scb329]. | after the pure culture of gluconobacter oxydans scb329 was researched, its growth curve was measured and its logarithmic phase was determined as between 4-24 h. after the microorganisms were havested in its logarithmic phase, the intact chromosome was prepared by agarose-embedded method. then the genome of scb329 was analyzed by pulsed-field gel electrophoresis. the result indicated that there are one chromosome and one great plasmid. the length of intact chromosome of scb329 has been estimated ... | 2001 | 12549188 |
| [studies on the genome size and structure of gluconobacter oxydans scb329]. | in the "two-step fermentation" of vitamin c synthesis, gluconobacter oxydans scb329 is responsible for the production of 2-keto-l-gulonic acid (2-klg), which is an important precuror of vitamin c synthesis. the intact chromosome was prepared from logarithmic phase cells by agaraseembedded method and was analysized by restriction endonucleases and contour-clamped homogeneous electric field pulsed-field gel electrophoresis (pfge). spe i (5-actagt) produced 24 fragments, ranging in size from 10 to ... | 2001 | 12552798 |
| [production of vitamin c precursor--2-keto-l-gulonic acid from d-sorbitol by mixed culture of microorganisms]. | gluconobacter oxydans scb329 only produce a little amount of 2-keto-l-gulonic acid(2-klg) from d-sorbitol when growing alone; while gluconobacter sp. scb110 can transform d-sorbitol to l-sorbose and can not produce 2-klg. 2-keto-l-gulonic acid, the precursor of l-ascorbic acid (vitamin c) synthesis, was prepared directly with a high efficiency from d-sorbitol by mixed culture of microorganism, which comprised gluconobacter sp. scb110 and gluconobacter oxydans scb329. the fermentation product fro ... | 2001 | 12552828 |
| cloning and expression of the gene encoding catalytic subunit of thermostable glucose dehydrogenase from burkholderia cepacia in escherichia coli. | we have cloned a 1620-nucleotide gene encoding the catalytic subunit (alpha subunit) of a thermostable glucose dehydrogenase (gdh) from burkholderia cepacia. the fad binding motif was found in the n-terminal region of the alpha subunit. the deduced primary structure of the alpha subunit showed about 48% identity to the catalytic subunits of sorbitol dehydrogenase (sdh) from gluconobacter oxydans and 2-keto-d-gluconate dehydrogenases (2kgdh) from erwinia herbicola and pantoea citrea. the alpha su ... | 2003 | 12573242 |
| novel enzymatic method for the production of xylitol from d-arabitol by gluconobacter oxydans. | microorganisms capable of producing xylitol from d-arabitol were screened for. of the 420 strains tested, three bacteria, belonging to the genera acetobacter and gluconobacter, produced xylitol from d-arabitol when intact cells were used as the enzyme source. among them, gluconobacter oxydans atcc 621 produced 29.2 g/l xylitol from 52.4 g/l d-arabitol after incubation for 27 h. the production of xylitol was increased by the addition of 5% (v/v) ethanol and 5 g/l d-glucose to the reaction mixture ... | 2002 | 12596856 |
| construction of a vector plasmid for use in gluconobacter oxydans. | a host vector system in gluconobacter oxydans was constructed. an acetobacter-escherichia coli shuttle vector was introduced with the efficiency of 10(4) transformants/microg of dna. next, aiming for a self-cloning vector, we found a cryptic plasmid (which we named pag5) of 5648 bp in g. oxydans strain ifo 3171, and sequenced the nucleotides. the plasmid seemed to have only one open reading flame (orf) for a possible replication protein. shuttle vectors of gluconobacter-e. coli were constructed ... | 2003 | 12619700 |
| 5-keto-d-gluconate production is catalyzed by a quinoprotein glycerol dehydrogenase, major polyol dehydrogenase, in gluconobacter species. | acetic acid bacteria, especially gluconobacter species, have been known to catalyze the extensive oxidation of sugar alcohols (polyols) such as d-mannitol, glycerol, d-sorbitol, and so on. gluconobacter species also oxidize sugars and sugar acids and uniquely accumulate two different keto-d-gluconates, 2-keto-d-gluconate and 5-keto-d-gluconate, in the culture medium by the oxidation of d-gluconate. however, there are still many controversies regarding their enzyme systems, especially on d-sorbit ... | 2003 | 12676670 |
| membrane-bound d-sorbitol dehydrogenase of gluconobacter suboxydans ifo 3255--enzymatic and genetic characterization. | gluconobacter strains effectively produce l-sorbose from d-sorbitol because of strong activity of the d-sorbitol dehydrogenase (sldh). l-sorbose is one of the important intermediates in the industrial vitamin c production process. two kinds of membrane-bound sldhs, which consist of three subunits, were reportedly found in gluconobacter strains [agric. biol. chem. 46 (1982) 135,fems microbiol. lett. 125 (1995) 45]. we purified a one-subunit-type sldh (80 kda) from the membrane fraction of glucono ... | 2003 | 12686146 |
| cloning of the xylitol dehydrogenase gene from gluconobacter oxydans and improved production of xylitol from d-arabitol. | xylitol dehydrogenase (xdh) was purified from the cytoplasmic fraction of gluconobacter oxydans atcc 621. the purified enzyme reduced d-xylulose to xylitol in the presence of nadh with an optimum ph of around 5.0. based on the determined nh2-terminal amino acid sequence, the gene encoding xdh was cloned, and its identity was confirmed by expression in escherichia coli. the xdh gene encodes a polypeptide composed of 262 amino acid residues, with an estimated molecular mass of 27.8 kda. the deduce ... | 2003 | 12723607 |
| improved selectivity of microbial biosensor using membrane coating. application to the analysis of ethanol during fermentation. | a ferricyanide mediated microbial biosensor for ethanol detection was prepared by surface modification of a glassy carbon electrode. the selectivity of the whole gluconobacter oxydans cell biosensor for ethanol determination was greatly enhanced by the size exclusion effect of a cellulose acetate (ca) membrane. the use of a ca membrane increased the ethanol to glucose sensitivity ratio by a factor of 58.2 and even the ethanol to glycerol sensitivity ratio by a factor of 7.5 compared with the use ... | 2003 | 12788555 |
| glucose oxidation by gluconobacter oxydans: characterization in shaking-flasks, scale-up and optimization of the ph profile. | in this study, the advantage of a novel measuring device for the online determination of oxygen and carbon dioxide transfer rates in shaking-flasks is reported for glucose oxidation by gluconobacter oxydans. in this fermentation process, this device was used for the characterization of the oxidation pattern of different strains. g. oxydans ncimb 8084 forms 2,5-diketogluconate from d-glucose in a multi-stage process via three different membrane-bound dehydrogenases. this strain was chosen for a s ... | 2003 | 12835926 |
| acetobacter intermedius, sp. nov. | strains of a new species in the genus acetobacter, for which we propose the name a. intermedius sp. nov., were isolated and characterized in pure culture from different sources (kombucha beverage, cider vinegar, spirit vinegar) and different countries (switzerland, slovenia). the isolated strains grow in media with 3% acetic acid and 3% ethanol as does a. europaeus, do, however, not require acetic acid for growth. these characteristics phenotypically position a. intermedius between a. europaeus ... | 1998 | 13678040 |
| polyol dehydrogenases of gluconobacter oxydans. | | 1965 | 14284764 |