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in vitro synthesis and properties of pectin/acetobacter xylinus cellulose compositespectin and cellulose are major components of most primary cell walls, yet little is known about the way in which they interact either during assembly or in subsequent functional performance of the wall. as a mimic of cell wall assembly, we studied the formation of molecular composites formed by deposition of cellulose from acetobacter xylinus into pectin/calcium systems, and the molecular, architectural and mechanical properties of the composites obtained. the formation of interpenetrating cellu ...199910571862
13c and 1h nmr study of cellulose metabolism by fibrobacter succinogenes s85.fibrobacter succinogenes s85, a cellulolytic rumen bacterium, is very efficient in degrading lignocellulosic substrates and could be used to develop a biotechnological process for the treatment of wastes. in this work, the metabolism of cellulose by f. succinogenes s85 was investigated using in vivo 13c nmr and 13c-filtered spin-echo difference 1h nmr spectroscopy. the degradation of unlabelled cellulose synthesised by acetobacter xylinum was studied indirectly, in the presence of [1-13c]glucose ...200010674213
bacterial cellulose production by acetobacter xylinum in a 50-l internal-loop airlift reactor.bacterial cellulose (bc) production was realized in a batch cultivation of acetobacter xylinum subsp. sucrofermentans bpr2001 in a 50-l internal-loop airlift reactor. when the bacterium was cultivated with air supply, 3.8 g/l of bc was produced after 67 hours. when oxygen-enriched gas was supplied, the concentration of bc was doubled and the production rate of bc was 0.116 g/l. h, which was two times higher than that of air-supplied culture and comparable to that in a mechanically agitated stirr ...200010745203
asaia bogorensis gen. nov., sp. nov., an unusual acetic acid bacterium in the alpha-proteobacteria.eight gram-negative, aerobic, rod-shaped and peritrichously flagellated strains were isolated from flowers of the orchid tree (bauhinia purpurea) and of plumbago (plumbago auriculata), and from fermented glutinous rice, all collected in indonesia. the enrichment culture approach for acetic acid bacteria was employed, involving use of sorbitol medium at ph 3.5. all isolates grew well at ph 3.0 and 30 degrees c. they did not oxidize ethanol to acetic acid except for one strain that oxidized ethano ...200010758893
molecular identification of acetobacter isolates from submerged vinegar production, sequence analysis of plasmid pjk2-1 and application in the development of a cloning vector.three new acetobacter strains were isolated from vinegar. by plasmid profiling they were recognized as genotypically different from each other. sequencing of the genes for 16s and 23s rrna and dna-dna hybridization of total dna against dna of all type strains of acetobacter identified acetobacter strains jk2 and v3 as a. europaeus, and acetobacter strain jk3 as a. intermedius. in contrast to the type strain of a. europaeus (dsm 6160), a. europaeus jk2 and v3 do not require acetic acid for growth ...200010772468
natural endophytic occurrence of acetobacter diazotrophicus in pineapple plants.the presence of endophytic acetobacter diazotrophicus was tested for pineapple plants (ananas comosus [l.] merr.) grown in the field. diazotrophic bacteria were isolated from the inner tissues of surface sterilized roots, stems, and leaves of pineapple plants. phenotypic tests permitted the selection of presumptive nitrogen-fixing a. diazotrophicus isolates. restriction fragment length polymorphisms (rflps) of small subunit (ssu) rdna using total dna digested with endonuclease sphi and with endo ...200010790517
cloning, sequencing, and expression of udp-glucose pyrophosphorylase gene from acetobacter xylinum brc5.a udp-glucose pyrophosphorylase (ugpase) gene from acetobacter xylinum brc5 has been cloned, sequenced, and expressed in escherichia coli. the gene consists of 867 nucleotides and encodes a polypeptide of 289 amino acid residues with a calculated molecular mass of 31,493 da. the amino acid sequences of the enzyme showed an 85.8% identity to those of an enzyme from a. xilinum atcc 23768. a polyhistidine-ugpase fusion enzyme was expressed and purified from the transformed e. coli. the enzyme showe ...200010803949
fermentation of a bacterial cellulose/xylan composite by mixed ruminal microflora: implications for the role of polysaccharide matrix interactions in plant cell wall biodegradability.growth of the cellulose-synthesizing bacterium acetobacter xylinum atcc 53524 in media supplemented with 5% (w/v) glucose and 0.2% (w/v) of a water-soluble, nearly linear xylan from tobacco stalks resulted in the synthesis of a highly crystalline composite having a xylose/glucose ratio ranging from 0.06 to 0.24. the digestion of one composite (88% cellulose/12% xylan) by mixed ruminal microflora displayed kinetics of gas production similar to those of an unassociated mixture of the two component ...200010820086
genetic characteristics of cellulose-forming acetic acid bacteria identified phenotypically as gluconacetobacter xylinus.gluconacetobacter xylinus (=acetobacter xylinum) shows variety in acid formation from sugars and sugar-alcohols. toyosaki et al. proposed new subspecies of g. xylinus (=acetobacter xylinum) subsp. sucrofermentans in point of acid formation from sucrose and a homology index of 58.2% with the type strain of g. xylinus subsp. xylinus in dna-dna hybridization experiments. we tried dna-dna hybridization to clarify relationship between acid formation from sugars and classification of g. xylinus. the g ...200010830489
isolation of a novel insertion sequence from mycobacterium fortuitum using a trap vector based on inactivation of a lacz reporter gene.an insertion sequence of mycobacterium fortuitum has been isolated using a trap vector following insertion in and inactivation of the lacz reporter gene. the trap vector is a temperature-sensitive (ts) escherichia coli-mycobacterium shuttle plasmid, pcd4, which contains ts orim, the kanamycin-resistance gene as a selection marker and a lacz expression cassette. the ts mutation present in pcd4 functions in mycobacteria and enables screening for transposable elements from the mycobacterial genome ...200010832643
phytanyl-pyrophosphate-linked substrate for a bacterial alpha-mannosyltransferase.the biochemical characterization of bacterial glycosyltransferases involved in the assembly of cell-wall-associated polysaccharides is often hindered by the lack of the appropriate undecaprenyl-pyrophosphate-linked acceptor substrate. in order to find a suitable synthetic substrate for the alpha1,3-mannosyltransferase acea from acetobacter xylinum, phytanyl-pyrophosphate-linked cellobiose was prepared. in the presence of gdp-[14c]mannose and recombinant acea, the phytanyl-pyrophosphate-linked ce ...200010872841
identification of acetic acid bacteria by restriction fragment length polymorphism analysis of a pcr-amplified fragment of the gene coding for 16s rrna.acetic acid bacteria (aab) irreversibly spoil wines and represent a serious problem. limited studies on the ecology of aab during winemaking have been done due to the lack of rapid and precise techniques for their identification. rflp analysis of pcr-amplified fragment of 16s rdna was performed on aab reference strains. the amplified rdnas were approximately 870-bp long for all aab species while no amplicons were detected for lactic acid bacteria and yeasts. out of the four restriction enzymes t ...200010886617
hypoglycemic activity of bio-tea in mice.administration of bio-tea (1.71 ml/kg) to normal albino mice caused hypoglycemia after 30 min which reached to maximum after 2 hr with a significant decrease in blood sugar level (bsl) and became normal beyond 8 hr. in alloxan-induced diabetic albino mice, repeated treatments of bio-tea for 3 days (five doses) brought about a significant fall in mean bsl. continuous decrease in bsl was observed after 4 hr of administration of last dose of bio-tea. hypoglycemic effect was persistent in alloxan-in ...200010927873
functional bradyrhizobium japonicum nifa expression under a hybrid nptii-nifh promoter in e. coli and acetobacter diazotrophicus srt4.a hybrid promoter consisting of the in tandem fusion of the tn5 nptii and the klebsiella pneumoniae nifh promoters was constructed to study the functionality of the nif genes transcriptional activator nifa from bradyrhizobium japonicum in two different host bacteria. beta-galactosidase experiments in e. coli revealed that the hybrid nptii-nifh promoter can behave as a constitutive or a nifa-inducible promoter depending on the aeration conditions. expression of the b. japonicum nifa from the hybr ...199810932742
in vitro determined kinetic properties of mutant phosphoglucomutases and their effects on sugar catabolism in escherichia coli.based on primary amino acid sequence comparisons with other phosphoglucomutases, 12 conserved residues in the acetobacter xylinum phosphoglucomutase (celb) were substituted by site-directed mutagenesis, resulting in mutant enzymes with kcat values [glucose-1-phosphate (g-1-p) to glucose-6-phosphate] ranging from 0 to 46% relative to that of the wild-type enzyme. in combination with a versatile set of plasmid expression vectors these proteins were used in a metabolic engineering study on sugar ca ...200010935726
bacterial response to acetate challenge: a comparison of tolerance among species.although acetate formation and tolerance are important criteria for various aspects of biotechnological process development, available studies on acetate tolerance in different species are disparate. we evaluate the response of eight bacterial strains, including two variants of escherichia coli, two variants of staphylococcus capitis, and one each of acetobacter aceti, gluconobacter suboxydans, lactobacillus acetotolerans, and l. bulgaricus, to acetate challenges under identical conditions. our ...200010968640
azospirillum, a free-living nitrogen-fixing bacterium closely associated with grasses: genetic, biochemical and ecological aspects.azospirillum represents the best characterized genus of plant growth-promoting rhizobacteria. other free-living diazotrophs repeatedly detected in association with plant roots, include acetobacter diazotrophicus, herbaspirillum seropedicae, azoarcus spp. and azotobacter. four aspects of the azospirillum-plant root interaction are highlighted: natural habitat, plant root interaction, nitrogen fixation and biosynthesis of plant growth hormones. each of these aspects is dealt with in a comparative ...200010978548
productivity enhancement in l-sorbose fermentation using oxygen vector.sorbose, an intermediate of vitamin-c is produced by biological oxidation of sorbitol by acetobacter suboxydans. the utility of oxygen vector (n-hexadecane) in enhancing the sorbose accumulation and its productivity was examined for sorbitol to sorbose bioconversion process. shake flask fermentations were conducted using 1% to 6% (v/v) n-hexadecane. higher sorbose production was observed in shake flask containing 1-4% n-hexadecane as compared to shake flasks without n-hexadecane. a maximum of 82 ...200010978777
cloning and sequencing of the levansucrase gene from acetobacter xylinum nci 1005.the levansucrase gene (lsxa) was cloned from the genomic dna of acetobacter xylinum nci 1005, and the nucleotide sequence of the lsxa gene (1,293 bp) was determined. the deduced amino acid sequence of the lsxa gene showed 57.4% and 46.2% identity with the levansucrases from zymomonas mobilis and erwinia amylovora, respectively, while only 35.2% identity with that from acetobacter diazotrophicus. the gene product of lsxa (lsxa) that was overproduced in e. coli coded for a polypeptide of molecular ...200010997873
identification of essential amino acids in the bacterial alpha -mannosyltransferase acea.the alpha-mannosyltransferase acea from acetobacter xylinum belongs to the cazy family 4 of retaining glycosyltransferases. we have identified a series of either highly conserved or invariant residues that are found in all family 4 enzymes as well as other retaining glycosyltransferases. these residues included glu-287 and glu-295, which comprise an ex(7)e motif and have been proposed to be involved in catalysis. alanine replacements of each conserved residue were constructed by site-directed mu ...200011001941
binding of soluble glycoproteins from sugarcane juice to cells of acetobacter diazotrophicus.sugarcane produces two different pools of glycoproteins containing a heterofructan as glycidic moiety, tentatively defined as high-molecular mass (hmmg) and mid-molecular mass (mmmg) glycoproteins. both kinds of glycoproteins can be recovered in sugarcane juice. fluorescein-labelled glycoproteins are able to bind to acetobacter diazotrophicus cells, a natural endophyte of sugarcane. this property implies the aggregation of bacterial cells in liquid culture after addition of hmmg or mmmg. anionic ...200011032311
the carbon source influences the energetic efficiency of the respiratory chain of n2-fixing acetobacter diazotrophicus.acetobacter diazotrophicus is a diazotrophic bacterium that colonizes sugarcane tissues. glucose is oxidized to gluconate in the periplasm prior to uptake and metabolism. a membrane-bound glucose dehydrogenase quinoenzyme [which contains pyrroloquinoline quinone (pqq) as the prosthetic group] is involved in that oxidation. gluconate is oxidized further via the hexose monophosphate pathway and tricarboxylic acid cycle. a. diazotrophicus pal3 was grown in a chemostat with atmospheric nitrogen as t ...200011092633
characterization of a major cluster of nif, fix, and associated genes in a sugarcane endophyte, acetobacter diazotrophicus.a major 30.5-kb cluster of nif and associated genes of acetobacter diazotrophicus (syn. gluconacetobacter diazotrophicus), a nitrogen-fixing endophyte of sugarcane, was sequenced and analyzed. this cluster represents the largest assembly of contiguous nif-fix and associated genes so far characterized in any diazotrophic bacterial species. northern blots and promoter sequence analysis indicated that the genes are organized into eight transcriptional units. the overall arrangement of genes is most ...200011092875
cloning and characterization of thermostable endoglucanase (cel8y) from the hyperthermophilic aquifex aeolicus vf5.aquifex aeolicus is the hyperthermophilic bacterium known, with growth-temperature maxima near 95 degrees c. the cel8y gene, encoding a thermostable endoglucanase (cel8y) from aquifex aeolicus vf5, was cloned into a vector for expression and expressed in escherichia coli xl1-blue. a clone of 1.7 kb fragment containing endoglucanase activity, designated pkycy100, was sequenced and found to contain an orf of 978 bp encoding a protein of 325 amino acid residues, with a calculated molecular mass of ...200011118302
ggdef domain is homologous to adenylyl cyclase.the ggdef domain is detected in many prokaryotic proteins, most of which are of unknown function. several bacteria carry 12-22 different ggdef homologues in their genomes. conducting extensive profile-based searches, we detect statistically supported sequence similarity between ggdef domain and adenylyl cyclase catalytic domain. from this homology, we deduce that the prokaryotic ggdef domain is a regulatory enzyme involved in nucleotide cyclization, with the fold similar to that of the eukaryoti ...200111119645
effect of glycine betaine on osmoadaptation of propionibacterium acidipropionici cultivated in elevated osmolarities.the sensitivity of industrial strains acetobacter aceti, gluconobacter frateurii, and propionibacterium acidipropionici to osmotic stress was studied. growth of a. aceti and g. frateurii was totally inhibited at 0.4 m nacl concentration, but p. acidipropionici was able to grow on a medium containing 1.2 m nacl. addition of glycine betaine to the medium had no detectable osmoprotective effect on a. aceti and g. frateurii cultivations in elevated nacl concentrations, but it enabled cells of p. aci ...200011131399
analysis of bacterial communities in the rhizosphere of chrysanthemum via denaturing gradient gel electrophoresis of pcr-amplified 16s rrna as well as dna fragments coding for 16s rrna.the effect of developing chrysanthemum roots on the presence and activity of bacterial populations in the rhizosphere was examined by using culture-independent methods. nucleic acids were extracted from rhizosphere soil samples associated with the bases of roots or root tips of plants harvested at different stages of development. pcr and reverse transcriptase (rt) pcr were used to amplify 16s ribosomal dna (rdna) and 16s rrna, respectively, and the products were subjected to denaturing gradient ...200111133442
gluconacetobacter entanii sp. nov., isolated from submerged high-acid industrial vinegar fermentations.acetic acid bacteria have been isolated from submerged high-acid spirit vinegar fermentations in the southern part of germany. four strains (lth 4560t, lth 4341, lth 4551 and lth 4637) were characterized in more detail and it was revealed that they have in common certain properties such as requirement of acetic acid, ethanol and glucose for growth, and no over-oxidation of acetate. growth occurs only at total concentrations (sum of acetic acid and ethanol) exceeding 6.0%. a method for their pres ...200011155975
transfer of acetobacter oboediens sokollek et al 1998 and acetobacter intermedius boesch et al. 1998 to the genus gluconacetobacter as gluconacetobacter oboediens comb. nov. and gluconacetobacter intermedius comb. nov.acetobacter oboediens sokollek et al. 1998 and acetobacter intermedius boesch et al. 1998 are transferred to the genus gluconacetobacter as gluconacetobacter oboediens comb. nov. and gluconacetobacter intermedius comb. nov. because, on the basis of their 16s rrna gene sequences, the type strains of both species are located in the cluster of the genus gluconacetobacter along with those of gluconacetobacter xylinus, gluconacetobacter europaeus, gluconacetobacter hansenii, gluconacetobacter liquefa ...200011155999
characterization of acetic acid bacteria in traditional acetic acid fermentation of rice vinegar (komesu) and unpolished rice vinegar (kurosu) produced in japan.bacterial strains were isolated from samples of japanese rice vinegar (komesu) and unpolished rice vinegar (kurosu) fermented by the traditional static method. fermentations have never been inoculated with a pure culture since they were started in 1907. a total of 178 isolates were divided into groups a and b on the basis of enterobacterial repetitive intergenic consensus-pcr and random amplified polymorphic dna fingerprinting analyses. the 16s ribosomal dna sequences of strains belonging to eac ...200111157275
fructo-oligosaccharides production by the gluconacetobacter diazotrophicus levansucrase expressed in the methylotrophic yeast pichia pastoris.levansucrase (lsda) (ec 2.4.1.10) from gluconacetobacter diazotrophicus (formerly acetobacter diazotrophicus) yields high levels of fructo-oligosaccharides (fos) from sucrose. a dna fragment encoding the precursor lsda lacking the first 57 amino acids was fused to the pho1 signal sequence under the control of the pichia pastoris-alcohol oxidase 1 (aox1) promoter. methanol induction of a p. pastoris strain harboring a single copy of the lsda expression cassette integrated in the genome resulted i ...200111166804
enzymes involved in the glycidaldehyde (2,3-epoxy-propanal) oxidation step in the kinetic resolution of racemic glycidol (2,3-epoxy-1-propanol) by acetobacter pasteurianus.it is already known that kinetic resolution of racemic glycidol (2,3-epoxy-1-propanol) takes place when acetobacter pasteurianus oxidizes the compound to glycidic acid (2,3-epoxy-propionic acid) with glycidaldehyde (2,3-epoxy-propanal) proposed to be the transient seen in this conversion. since inhibition affects the feasibility of a process based on this conversion in a negative sense, and the chemical reactivity of glycidaldehyde predicts that it could be the cause for the phenomena observed, ...200111166817
optimization of fermentation conditions for the production of bacterial cellulose by a newly isolated acetobacter sp. a9 in shaking cultures.the optimum fermentation conditions for the production of cellulose by a newly isolated acetobacter sp. a9 were determined by shaken cultures. the strain was able to produce cellulose at 25-30 degrees c with a maximum at 30 degrees c. cellulose production occurred at ph 4.5-7.5 with a maximum at ph 6.5. the improved medium composition was 4% (w/v) glucose, 0.1% (w/v) yeast extract, 0.7% (w/v) polypeptone and 0.8% (w/v) na(2)hpo(4).12h(2)o. under these culture conditions, 3.8 g/l cellulose was pr ...200111171030
higher plant cellulose synthases.summary: cellulose, an aggregate of unbranched polymers of beta-1,4-linked glucose residues, is the major component of wood and thus paper, and is synthesized by plants, most algae, some bacteria and fungi, and even some animals. the genes that synthesize cellulose in higher plants differ greatly from the well-characterized genes found in acetobacter and agrobacterium sp. more correctly designated as 'cellulose synthase catalytic subunits', plant cellulose synthase (cesa) proteins are integral m ...200011178255
isolation and characterization of thermotolerant gluconobacter strains catalyzing oxidative fermentation at higher temperatures.thermotolerant acetic acid bacteria belonging to the genus gluconobacter were isolated from various kinds of fruits and flowers from thailand and japan. the screening strategy was built up to exclude acetobacter strains by adding gluconic acid to a culture medium in the presence of 1% d-sorbitol or 1% d-mannitol. eight strains of thermotolerant gluconobacter were isolated and screened for d-fructose and l-sorbose production. they grew at wide range of temperatures from 10 degrees c to 37 degrees ...200011193396
evaluation of health aspects of kojic acid in food.kojic acid is a fungal metabolite commonly produced by many species of aspergillus, acetobacter, and penicillium. the aspergillus flavus group has traditionally been used in the production of a number of foods, including miso (soybean paste), shoyu (soy sauce), and sake. kojic acid is widely used as a food additive for preventing enzymatic browning, and in cosmetic preparations as a skin-lightening or bleaching agent. because kojic acid is often produced during the fermentation of historically u ...200111259181
the multicellular morphotypes of salmonella typhimurium and escherichia coli produce cellulose as the second component of the extracellular matrix.production of cellulose has been thought to be restricted to a few bacterial species such as the model organism acetobacter xylinus. we show by enzymatic analysis and mass spectrometry that, besides thin aggregative fimbriae, the second component of the extracellular matrix of the multicellular morphotype (rdar) of salmonella typhimurium and escherichia coli is cellulose. the bcsa, bcsb, bcsz and bcsc genes responsible for cellulose biosynthesis are not regulated by agfd, the positive transcript ...200111260463
structure and conformation of a novel genetically engineered polysaccharide p2.a new exocellular polysaccharide (p2) has been produced by the manipulation of a glycosyl transferase gene (acep) involved in the biosynthesis of the polysaccharide acetan by the bacterium acetobacter xylinum strain cke5. the p2 polysaccharide has been studied by methylation analysis, reductive cleavage, and 1h and 13c nmr spectroscopy. the data are consistent with the structure predicted when the acep gene is deactivated: [molecular structure: see text]. the effect of cooling on proton nmr line ...200111270811
comparison of benefit to sugarcane plant growth and 15n2 incorporation following inoculation of sterile plants with acetobacter diazotrophicus wild-type and nif- mutants strains.the ability of the nitrogen-fixing bacterial endophyte acetobacter diazotrophicus strain pal5 to enhance the growth of sugarcane sp70-1143 was evaluated in the growth chamber, greenhouse, and field by comparing plants inoculated with wild-type and nif mutant mad3a in two independent experiments. the wild-type and nif mutant strains colonized sugarcane plants equally and persisted in mature plants. in n-deficient conditions, sugarcane plants inoculated with a. diazotrophicus pal5 generally grew b ...200111277433
phosphodiesterase a1, a regulator of cellulose synthesis in acetobacter xylinum, is a heme-based sensor.the phosphodiesterase a1 protein of acetobacter xylinum, axpdea1, is a key regulator of bacterial cellulose synthesis. this phosphodiesterase linearizes cyclic bis(3'-->5')diguanylic acid, an allosteric activator of the bacterial cellulose synthase, to the ineffectual pgpg. here we show that axpdea1 contains heme and is regulated by reversible binding of o(2) to the heme. apo-axpdea1 has less than 2% of the phosphodiesterase activity of holo-axpdea1, and reconstitution with hemin restores full a ...200111297407
the est1 regulation depends on the oxygen concentration in acetobacter pasteurianus.the regulation mechanism for expression of the ethanol inducible esterase gene, est1, was investigated in a. pasteurianus. deletion analysis of the 5' non coding region of est1 showed that the fnr-binding consensus sequence is important in the induction of est1 by ethanol. cells grown under oxygen starvation produced esterase-1 in not only the presence but also the absence of ethanol. these results suggest that the induction of est1-expression depends on the oxygen concentration, and the gene ma ...200111330700
a multiphasic hollow fiber reactor for the whole-cell bioconversion of 2-methyl-1,3-propanediol to (r)-beta-hydroxyisobutyric acid.this paper describes the bioconversion of 2-methyl-1,3-propanediol to (r)-beta-hydoxyisobutyric acid (hiba) by acetobacter alei in a hollow fiber membrane bioreaction system arrangement that allows the integration of three liquid phases: the aqueous bioconversion phase, the organic phase consisting of a solution of trioctyl phosphine oxide (topo) in isooctane, and the third phase consisting of a basic stripping solution that allows reextraction of hiba from the organic phase. a comparison of hib ...200111386867
bioskin as an affinity matrix for the separation of glycoproteins.bioskin is a natural product produced by a mixed culture of acetobacter xylinum, saccharomyces cerevisiae and s. pombe cultured on media containing sucrose. it is of fibrillar nature able to retain some proteins, such as cytochrome c, by adsorption, and mainly composed of glucosamine and n-acetyl-d-glucosamine. this makes it possible that, at an adequate ph value, proteins charged as polyanionic molecules, such as catalase, can be retained by ionic adsorption using the positively charged amino g ...200111403492
isolation and characterization of a veratrol:corrinoid protein methyl transferase from acetobacterium dehalogenans.from 3-methoxyphenol-grown cells of acetobacterium dehalogenans, an inducible enzyme was purified that mediated the transfer of the methyl groups of veratrol (1,2-dimethoxybenzene) to a corrinoid protein enriched from the same cells. in this reaction, veratrol was converted via 2-methoxyphenol to 1,2-dihydroxybenzene. the veratrol:corrinoid protein methyl transferase, designated mtiver, had an apparent molecular mass of about 32 kda. with respect to the n-terminal amino acid sequence and other c ...200111409548
structure--function characterization of cellulose synthase: relationship to other glycosyltransferases.a combined structural and functional model of the catalytic region of cellulose synthase is presented as a prototype for the action of processive beta-glycosyltransferases and other glycosyltransferases. a 285 amino acid segment of the acetobacter xylinum cellulose synthase containing all the conserved residues in the globular region was subjected to protein modeling using the genetic algorithm. this region folds into a single large domain with a topology exhibiting a mixed alpha/beta structure. ...200111430986
effect of addition of water-soluble polysaccharides on bacterial cellulose production in a 50-l airlift reactor.bacterial cellulose (bc) production was carried out in a batch cultivation of acetobacter xylinum in a 50-l internal loop airlift reactor by addition of water-soluble polysaccharides into the medium. when 0.1% (w/w) agar was added, bc production reached 8.7 g/l compared with 6.3 g/l in the control, and duration of the cultivation period to reach the maximum concentration of bc was almost half of that without addition of polysaccharides. during cultivation, bc was formed into pellets whose size w ...200111485444
novel nitrogen-fixing acetic acid bacteria, gluconacetobacter johannae sp. nov. and gluconacetobacter azotocaptans sp. nov., associated with coffee plants.diazotrophic bacteria were isolated, in two different years, from the rhizosphere and rhizoplane of coffee (coffea arabica l.) plants cultivated in mexico; they were designated as type dor and type sad isolates. they showed characteristics of the family acetobacteraceae, having some features in common with gluconacetobacter (formerly acetobacter) diazotrophicus, the only known n2-fixing species of the acetic acid bacteria, but they differed from this species with regard to several characteristic ...200111491326
glutamine synthetase from acetobacter diazotrophicus: properties and regulation.glutamine synthetase from acetobacter diazotrophicus, an endophyte originally isolated from sugarcane, was studied as a step in the identification of mechanisms underlying the role of a. diazotrophicus as a major supplier of fixed nitrogen to its host plant. the enzyme was purified and partially characterized. it was also shown that the enzyme is regulated by adenylylation in response to the nitrogen source. interestingly, there is no upregulation of the synthesis of the enzyme under diazotrophi ...200111520611
bacterial cellulose production under oxygen-enriched air at different fructose concentrations in a 50-liter, internal-loop airlift reactor.bacterial cellulose (bc) production by acetobacter xylinum subsp. sucrofermentans bpr2001 was carried out in a 50-1 internal-loop airlift reactor in air at an initial fructose concentration of 40 g/l. the bc production rate was 0.059 g/l per h. when oxygen-enriched air was supplied instead of air, the bc production rate increased to 0.093 g/l per h, and the bc yield was enhanced from 11% in air to 18%. when the initial fructose concentrations were varied from 30 to 70 g/l, the highest bc yield ( ...200111525613
direct incorporation of glucosamine and n-acetylglucosamine into exopolymers by gluconacetobacter xylinus (=acetobacter xylinum) atcc 10245: production of chitosan-cellulose and chitin-cellulose exopolymers.gluconacetobacter xylinus (=acetobacter xylinum) atcc 10245 incorporated 2-amino-2-deoxy-d-glucose (glucosamine) and 2-acetamido-2-deoxy-d-glucose (n-acetylglucosamine), but not 3-o-methyl-d-glucose or 2-deoxy-d-glucose into exopolymers. incorporation was confirmed by gas chromatography with and without mass spectrometry, fourier transform infrared, and 1h nuclear magnetic resonance. the average molar percentage of glucosamine and n-acetylglucosamine in the exopolymers was about 18%.200111525993
natural abundances of carbon isotopes in acetate from a coastal marine sediment.measurements of the natural abundances of carbon isotopes were made in acetate samples isolated from the anoxic marine sediment of cape lookout bight, north carolina. the typical value of the total acetate carbon isotope ratio (delta 13c) was -16.1 +/- 0.2 per mil. the methyl and carboxyl groups were determined to be -26.4 +/- 0.3 and -6.0 +/- 0.3 per mil, respectively, for one sample. the isotopic composition of the acetate is thought to have resulted from isotopic discriminations that occur ...198711539717
gravity effects on cellulose assembly.the effect of microgravity on cellulose synthesis using the model system of acetobacter xylinum was the subject of recent investigations using the national aeronautics and space administration's reduced gravity laboratory, a modified kc-135 aircraft designed to produce 20 sec of microgravity during the top of a parabolic dive. approximately 40 parabolas were executed per mission, and a period of 2 x g was integral to the pullout phase of each parabola. cellulose biosynthesis was initiated on aga ...199211541320
localization of c-di-gmp-binding protein with the linear terminal complexes of acetobacter xylinum.specific labeling of a single row of cellulose-synthesizing complexes (terminal complexes, tc subunits, tcs, or tc arrays) in acetobacter xylinum by antibodies raised against a 93-kda protein (the cyclic dignanylic acid-binding protein) has been demonstrated by using the sodium dodecyl sulfate (sds)-freeze-fracture labeling (frl) technique. the antibodies to the 93-kda protein specifically recognized the tc subunits on the protoplasmic fracture (pf) face of the outer membrane in a. xylinum; howe ...200111544230
structure of acetobacter cellulose composites in the hydrated state.the structure of composites produced by the bacterium acetobacter xylinus have been studied in their natural, hydrated, state. small-angle x-ray diffraction and environmental scanning electron microscopy has shown that the ribbons have a width of 500 a and contain smaller semi-crystalline cellulose microfibrils with an essentially rectangular cross-section of approximately 10 x 160 a(2). incubation of acetobacter in xyloglucan or pectin results in no changes in the size of either the microfibril ...200111589972
genetic data indicate that proteins containing the ggdef domain possess diguanylate cyclase activity.a conserved domain, called ggdef (referring to a conserved central sequence pattern), is detected in many procaryotic proteins, often in various combinations with putative sensory-regulatory components. most sequenced bacterial genomes contain several different ggdef proteins. the function of this domain has so far not been experimentally shown. through genetic complementation using genes from three different bacteria encoding proteins with ggdef domains as the only element in common, we present ...200111682196
multifunctional epoxy supports: a new tool to improve the covalent immobilization of proteins. the promotion of physical adsorptions of proteins on the supports before their covalent linkage.multifunctional supports containing epoxy groups are here proposed as a second generation of activated supports for covalent immobilization of enzymes following the epoxy chemistry on any type of support (hydrophobic or hydrophilic ones) under very mild experimental conditions (e.g., low ionic strength, neutral ph values, and low temperatures). these multifunctional supports have been easily prepared by modifying a small fraction (10-20%) of the epoxy groups contained in commercial epoxy support ...200011710205
proteins induced during adaptation of acetobacter aceti to high acetate concentrations.as a typical product of microbial metabolism, the weak acid acetate is well known for its cytotoxic effects. in contrast to most other microbes, the so-called acetic acid bacteria can acquire significant resistance to high acetate concentrations when properly adapted to such hostile conditions. to characterize the molecular events that are associated with this adaptation, we analyzed global protein expression levels during adaptation of acetobacter aceti by two-dimensional gel electrophoresis. a ...200111722895
pyruvate decarboxylase: a key enzyme for the oxidative metabolism of lactic acid by acetobacter pasteurianus.acetobacter pasteurianus, an obligately oxidative bacterium, is the first organism shown to utilize pyruvate decarboxylase (pdc) as a central enzyme for oxidative metabolism. in plants, yeast, and other bacteria, pdc functions solely as part of the fermentative ethanol pathway. during the growth of a. pasteurianus on lactic acid, the central intermediate pyruvate is cleaved to acetaldehyde and co(2) by pdc. acetaldehyde is subsequently oxidized to its final product, acetic acid. the presence of ...200111734888
biotransformations catalyzed by multimeric enzymes: stabilization of tetrameric ampicillin acylase permits the optimization of ampicillin synthesis under dissociation conditions.the importance of the stabilization of the quaternary structure of multimeric enzymes has been illustrated using a model reaction with great industrial relevance: the enzymatic synthesis of ampicillin from 6-amino penicillanic acid (6apa) and phenylglycine methyl ester (pgm) catalyzed by the tetrameric enzyme alpha-amino acid ester hydrolase from acetobacter turbidans. the stabilization of the multimeric structure of the enzyme was achieved by multi-subunit immobilization of the enzyme followed ...200111749160
cloning, sequence analysis, and expression in escherichia coli of the gene encoding an alpha-amino acid ester hydrolase from acetobacter turbidans.the alpha-amino acid ester hydrolase from acetobacter turbidans atcc 9325 is capable of hydrolyzing and synthesizing beta-lactam antibiotics, such as cephalexin and ampicillin. n-terminal amino acid sequencing of the purified alpha-amino acid ester hydrolase allowed cloning and genetic characterization of the corresponding gene from an a. turbidans genomic library. the gene, designated aeha, encodes a polypeptide with a molecular weight of 72,000. comparison of the determined n-terminal sequence ...200211772629
a gene encoding phosphatidylethanolamine n-methyltransferase from acetobacter aceti and some properties of its disruptant.phosphatidylcholine (pc) is a major component of membranes not only in eukaryotes, but also in several bacteria, including acetobacter. to identify the pc biosynthetic pathway and its role in acetobacter sp., we have studied acetobacter aceti ifo3283, which is characterized by high ethanol oxidizing ability and high resistance to acetic acid. the pmt gene of a. aceti, encoding phosphatidylethanolamine n-methyltransferase (pmt), which catalyzes methylation of phosphatidylethanolamine (pe) to pc, ...200111826972
cloning and sequencing of the beta-glucosidase gene from acetobacter xylinum atcc 23769.the beta-glucosidase gene (bglxa) was cloned from the genomic dna of acetobacter xylinum atcc 23769 and its nucleotide sequence (2200 bp) was determined. this bglxa gene was present downstream of the cellulose synthase operon and coded for a polypeptide of molecular mass 79 kda. the overexpression of the beta-glucosidase in a. xylinum caused a tenfold increase in activity compared to the wild-type strain. in addition, the action pattern of the enzyme was identified as g3ase activity. the deduced ...200111853314
cultivation of acetobacter xylinum for bacterial cellulose production in a modified airlift reactor.acetobacter xylinum for bacterial cellulose production was cultivated in a modified airlift reactor. better results were obtained from the modified reactor than from a conventional bubble column. after 72 h of cultivation, the final concentration of bacterial cellulose was 7.72 g/l and the productivity was 0.107 g/l per h in the modified airlift reactor. the concentration of bacterial cellulose was about three times higher than that produced in the conventional bubble column. moreover, the bacte ...200211916454
chemical and microbiological characterisation of kefir grains.chemical and microbiological composition of four argentinean kefir grains from different sources as well as characteristics of the corresponding fermented milk were studied. kefir grains cidca agk1, agk2 and agk4 did not show significant differences in their chemical and microbiological composition. in contrast, protein and yeast content of agk3 was higher than in the other grains. although grain microflora comprised lactobacilli, lactococcus, acetic acid bacteria and yeast, we found an importan ...200111928960
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 ...200211930953
a comparative resonance raman analysis of heme-binding pas domains: heme iron coordination structures of the bjfixl, axpdea1, ecdos, and mtdos proteins.the heme-pas is a specialized domain with which a broad class of signal-transducing heme proteins detect physiological heme ligands. such domains exhibit a wide range of ligand binding parameters, yet they are all expected to feature an alpha-beta heme binding fold and a predominantly hydrophobic heme distal pocket without a distal histidine. we have compared, for the first time, the resonance raman spectra of several heme-pass: the heme-binding domains of bradyrhizobium japonicum fixl, escheric ...200211939776
production of bacterial cellulose from alternate feedstocks.production of bacterial cellulose by acetobacter xylinum atcc 10821 and 23770 in static cultures was tested from unamended food process effluents. effluents included low-solids (ls) and high-solids (hs) potato effluents, cheese whey permeate (cw), or sugar beet raffinate (csb). strain 23770 produced 10% less cellulose from glucose than did strain 10821 and diverted more glucose to gluconate. unamended hs, cw, and csb were unsuitable for cellulose production by either strain, and ls was unsuitabl ...200111963879
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 ...200211976147
purification and characterization of membrane-bound malate dehydrogenase from acetobacter sp. sku 14.membrane-bound nad(p)-independent malate dehydrogenase (ec 1.1.99.16) was purified to homogeneity from the membrane of thermotolerant acetobacter sp. sku 14, an isolate from thailand. the enzyme was solubilized from the membrane fraction of glycerol-grown cells with 1% triton x-100 in the presence of 0.1 m kcl, and purified to homogeneity through steps of column chromatographies on deae-sephadex a-50 and deae-toyopearl in the presence of 0.1% triton x-100. the purified enzyme showed a single pro ...200211999402
identification of the catalytic residues of alpha-amino acid ester hydrolase from acetobacter turbidans by labeling and site-directed mutagenesis.the alpha-amino acid ester hydrolase from acetobacter turbidans atcc 9325 is capable of hydrolyzing and synthesizing the side chain peptide bond in beta-lactam antibiotics. data base searches revealed that the enzyme contains an active site serine consensus sequence gly-x-ser-tyr-x-gly that is also found in x-prolyl dipeptidyl aminopeptidase. the serine hydrolase inhibitor p-nitrophenyl-p'-guanidino-benzoate appeared to be an active site titrant and was used to label the alpha-amino acid ester h ...200212011065
purification and characterization of a novel polysaccharide involved in the pellicle produced by a thermotolerant acetobacter strain.acetobacter strains able to produce a thick pellicle at 37 degrees c were screened among many thermotolerant strains isolated from fruits in thailand. as a result, acetobacter sp. sku 1100 was selected as the producer of a relatively thick pellicle even when cultured at higher temperatures such as 37 degrees c or 40 degrees c. this strain could produce a pellicle polysaccharide in a shaking submerged culture as well as under static culture conditions. the polysaccharide was found to be attached ...200212036050
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 ...200212054243
molecular interactions in bacterial cellulose composites studied by 1d ft-ir and dynamic 2d ft-ir spectroscopy.specific strain-induced orientation and interactions in three acetobacter cellulose composites: cellulose (c), cellulose/pectin (cp) and cellulose/xyloglucan (cxg) were characterized by ft-ir and dynamic 2d ft-ir spectroscopies. on the molecular level, the reorientation of the cellulose fibrils occurred in the direction of the applied mechanical strain. the cellulose-network reorientation depends on the composition of the matrix, including the water content, which lubricates the motion of macrom ...200212062530
optimizing high strength acetic acid bioprocess by cognitive methods in an unsteady state cultivation.methods of adapting micro-organisms to an inhibiting factor in an active industrial bioprocess were examined with an acetic acid fermentation as model. with the aim of automatic control, a fuzzy-logic system was developed on the basis of the collected knowledge of skilled vinegar brewers. in a first step, this fuzzy system was to assess the actual adaptation degree of the bacteria on the basis of data from robust and reasonably priced sensors. from this information an appropriate setpoint value ...200212067520
cp/mas (13)c nmr study of cellulose and cellulose derivatives. 1. complete assignment of the cp/mas (13)c nmr spectrum of the native cellulose.the precise assignments of cross polarization/magic angle spinning (cp/mas) (13)c nmr spectra of cellulose i(alpha) and i(beta) were performed by using (13)c labeled cellulose biosynthesized by acetobacter xylinum (a. xylinum) atcc10245 strain from culture medium containing d-[1,3-(13)c]glycerol or d-[2-(13)c]glucose as a carbon source. on the cp/mas (13)c nmr spectrum of cellulose from d-[1,3-(13)c]glycerol, the introduced (13)c labeling were observed at c1, c3, c4, and c6 of the biosynthesized ...200212071760
cp/mas (13)c nmr study of cellulose and cellulose derivatives. 2. complete assignment of the (13)c resonance for the ring carbons of cellulose triacetate polymorphs.complex ring (13)c resonance lines of the cross-polarization/magic angle spinning (cp/mas) (13)c nmr spectra of cellulose triacetate (cta) i and cta ii were completely assigned, for the first time, by (13)c-enriched cta allomorphs. the (13)c-enriched cta i was prepared by heterogeneous acetylation of bacterial cellulose which was biosynthesized by acetobacter xylinum (a. xylinum) atcc10245 from culture medium containing d-(2-(13)c)-, d-(3-(13)c)-, or d-(5-(13)c)glucose as a carbon source, while ...200212071761
antimicrobial flavonoids from bolusanthus speciosus.a new isoflavanone namely 3,5,7,2',4'-pentahydroxy-8,3'-di(gamma,gamma-dimethylallyl)isoflavanone (bolusanthin ii) and four new pterocarpans identified as 3-hydroxy-6',6'-dimethylpyrano[2',3':1,2] [6a r,11a r]-8,9-methylenedioxypterocarpan (bolucarpan a), 3-hydroxy-6',6'-dimethyl-4',5'-dihydropyrano[2',3':1,2][6a r,11a r]- 8,9-methylenedioxypterocarpan (bolucarpan b), 3-hydroxy-9-methoxy-6',6'-dimethylpyrano-[2',3':1,2][6a r,11a r]-pterocarpan (bolucarpan c) and 3-hydroxy-9-methoxy-6',6'-dimethy ...200212142995
development of an optimized, simple chemically defined medium for bacterial cellulose production by acetobacter sp. a9 in shaking cultures.the genus acetobacter can synthesize cellulose when grown in an undefined medium containing glucose. by using the technique of the omission of a single medium component, an optimized and simple chemically defined medium was developed to support cellulose production by acetobacter sp. a9 in shaking culture. it contained 4.0% (w/v) glucose, 0.2% (w/v) (nh(4))(2)so(4), 0.25% (w/v) kh(2)po(4), 0.3% (w/v) na(2)hpo(4).12h(2)o, 0.05% (w/v) mgso(4).7h(2)o, 0.0002% (w/v) feso(4).7h(2)o, 0.00025% (w/v) h( ...200212149121
novel glycosyltransferase genes involved in the acetan biosynthesis of acetobacter xylinum.novel aceq and acer genes involved in the acetan biosynthesis of acetobacter xylinum were newly isolated. the homology search with dna data bank of japan indicated that aceq and acer were glycosyltransferases. their gene-disrupted mutants were obtained by homologous recombination using the tetracycline resistance gene and the electroporation method. by nmr and esi-ms analyses, aceq-disrupted mutant dq was found to secrete a water-soluble polysaccharide harboring the -man-glcua side chain and the ...200212150936
orf2 gene involves in the construction of high-order structure of bacterial cellulose.an orf2 gene located upstream of the cellulose synthase (bcs) operon of acetobacter xylinum bpr2001 was disrupted and a mutant (m2-2) was constructed. in static cultivation, the parent strain produced a tough, colorless, and insoluble cellulose pellicle, whereas m2-2 culture produced a thin, yellow, and fragile pellicle. the results of x-ray diffraction and 13c solid-state nmr indicated that the product of m2-2 is a mixture of cellulose i, cellulose ii, and amorphous cellulose. the cellulose i t ...200212150971
a nitrogen-fixing endophyte of sugarcane stems (a new role for the apoplast).the intercellular spaces of sugarcane (saccharum officinarum l.) stem parenchyma are filled with solution (determined by cryoscanning microscopy), which can be removed aseptically by centrifugation. it contained 12% sucrose (suc; ph 5.5.) and yielded pure cultures of an acid-producing bacterium (approximately 104 bacteria/ml extracted fluid) on n-poor medium containing 10% suc (ph 5.5). this bacterium was identical with the type culture of acetobacter diazotrophicus, a recently discovered n2-fix ...199412232271
fermentability of grape must after inhibition with dimethyl dicarbonate (dmdc).dimethyl dicarbonate (dmdc) was added to grape must and to synthetic media and results showed that, at 20 degrees c, 150 mg.l(-)(1) dmdc completely inhibited the fermentation of a grape must that was previously inoculated with 10(6) cells.ml(-)(1) saccharomyces bayanus and saccharomyces uvarum. brettanomyces intermedius, candida guilliermondii, hansenula jadinii, hansenula petersonii, kloeckera apiculata, pichia membranaefaciens, and saccharomyces cerevisiae were inhibited by 250 mg.l(-)(1). can ...200212236685
eca: control in ecosystems.although metabolic control analysis (mca) cannot be applied directly to microbial ecological systems because of mass conservation and stoichiometric constraints, we demonstrate here that hierarchical control analysis (hca) can be applied to such systems. we illustrate the approach for a particular ecosystem example of the biological synthesis of acetic acid from glucose, and uncover some surprising aspects to the control of this miniature ecosystem.200212241039
effects of acetan on production of bacterial cellulose by acetobacter xylinum.acetan is a water-soluble polysaccharide produced by a bacterial cellulose (bc) producer, acetobacter xylinum. an acetan-nonproducing mutant, ep1, was generated from wild-type a. xylinum bpr2001 by the disruption of acea, which may act to catalyze the first step of the acetan biosynthetic pathway in this bacterium. ep1 produced less bc than the wild-type strain. however, when ep1 was cultured in a medium containing acetan, bc production was stimulated and the final yield of bc was equivalent to ...200212353627
mechanical properties of primary plant cell wall analogues.mechanical effects of turgor pressure on cell walls were simulated by deforming cell wall analogues based on acetobacter xylinus cellulose under equi-biaxial tension. this experimental set-up, with associated modelling, allowed quantitative information to be obtained on cellulose alone and in composites with pectin and/or xyloglucan. cellulose was the main load-bearing component, pectin and xyloglucan leading to a decrease in modulus when incorporated. the cellulose-only system could be regarded ...200212355159
factors affecting the yield and properties of bacterial cellulose.acetobacter xylinum e(25) has been applied in our studies in order to find optimal culture conditions for effective bacterial cellulose (bc) production. the strain displays significantly higher stability in bc production under stationary culture conditions. in contrast, intensive agitation and aeration appear to drastically reduce cellulose synthesis since such conditions induced formation of spontaneous cellulose nonproducing mutants (cel-), which dominated in the culture. mutation frequency st ...200212355318
re-examination of the genus acetobacter, with descriptions of acetobacter cerevisiae sp. nov. and acetobacter malorum sp. nov.thirty-four acetobacter strains, representing acetobacter aceti, acetobacter pasteurianus, acetobacter pomorum, acetobacter peroxydans, acetobacter lovaniensis, acetobacter estunensis, acetobacter orleanensis, acetobacter indonesiensis and acetobacter tropicalis, were subjected to a polyphasic study that included dna-dna hybridizations, dna base ratio determinations, 16s rdna sequence analysis and phenotypic characterization. two novel species are proposed, acetobacter cerevisiae sp. nov. and ac ...200212361257
biodirected epitaxial nanodeposition of polymers on oriented macromolecular templates.biodirected epitaxial nanodeposition of polymers was achieved on a template with an oriented molecular surface. acetobacter xylinum synthesized a ribbon of cellulose i microfibrils onto a fixed, nematic ordered substrate of glucan chains with unique surface characteristics. the substrate directed the orientation of the motion due to the inverse force of the secretion during biosynthesis, and the microfibrils were aligned along the orientation of the molecular template. using real-time video anal ...200212376618
cloning of cellulose synthesis related genes from acetobacter xylinum atcc23769 and atcc53582: comparison of cellulose synthetic ability between strains.about 14.5 kb of dna fragments from acetobacter xylinum atcc23769 and atcc53582 were cloned, and their nucleotide sequences were determined. the sequenced dna regions contained endo-beta-1,4-glucanase, cellulose complementing protein, cellulose synthase subunit ab, c, d and beta-glucosidase genes. the results from a homology search of deduced amino acid sequences between a. xylinum atcc23769 and atcc53582 showed that they were highly similar. however, the amount of cellulose production by atcc53 ...200212465714
identification of acetobacter strains isolated from indonesian sources, and proposals of acetobacter syzygii sp. nov., acetobacter cibinongensis sp. nov., and acetobacter orientalis sp. nov.forty-six strains of acetic acid bacteria newly isolated from flowers, fruits, and fermented foods collected in indonesia were taxonomically studied. they were gram-negative rods, produced acetic acid from ethanol, oxidized acetate and lactate to co(2) and h(2)o, and had q-9 as the major ubiquinone system. on the basis of dna-dna similarity, all strains studied, including type strains and reference strains of the genus acetobacter, were separated into eleven groups (groups i to xi). of the 46 is ...200112483554
systematic study of the genus acetobacter with descriptions of acetobacter indonesiensis sp. nov., acetobacter tropicalis sp. nov., acetobacter orleanensis (henneberg 1906) comb. nov., acetobacter lovaniensis (frateur 1950) comb. nov., and acetobacter estunensis (carr 1958) comb. nov.thirty-one acetobacter strains obtained from culture collections and 45 acetobacter strains isolated from indonesian sources were investigated for their phenotypic characteristics, ubiquinone systems, dna base compositions, and levels of dna-dna relatedness. of 31 reference strains, six showed the presence of ubiquinone 10 (q-10). these strains were eliminated from the genus acetobacter. the other 25 reference strains and 45 indonesian isolates were subjected to a systematic study and separated ...200012483588
x-ray analysis of two antibiotic-synthesizing bacterial ester hydrolases: preliminary results.alpha-amino-acid ester hydrolases are multimeric enzymes of potential use in antibiotic production. knowledge of their structure could help to engineer these enzymes into economically viable biocatalysts. the alpha-amino-acid ester hydrolases from xanthomonas citri and acetobacter turbidans have been crystallized. the x. citri enzyme crystallizes in a primitive monoclinic space group (unit-cell parameters a = 90.1, b = 125.8, c = 132.1 a, beta = 90.9 degrees ). the a. turbidans enzyme crystalliz ...200312499556
[medusomyces (tea fungus): scientific history, composition, physiology, and metabolism].the literature data on medusomyces published since 1913 are discussed. different versions of appearance and distribution of this microorganism are considered. the features of its structure, metabolism and growth conditions are analyzed. it is shown that the tea fungus is a symbiosis is of several sorts of yeast and acetic acid bacteria. evidence is presented indicating that fermented tea fungus has a therapeutic effect and can be applied in medicine. it was proved, that the antimicrobial propert ...200212500577
taxonomic heterogeneity of strains comprising gluconacetobacter hansenii.the taxonomic standing of gluconacetobacter hansenii was clarified through phenotypic characteristics, quinones, dna base composition, dna relatedness, and the production of gluconic and ketogluconic acids from glucose. all strains that gosselé et al. (syst. appl. microbiol., 4, 338-368, 1983) employed in the establishment of acetobacter hansenii (=g. hansenii) were used in this study. phenotypic differences were shown among the strains of g. hansenii, suggesting heterogeneity within the species ...199912501359
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 ...199912501398
[cloning and expression of d-arabitol dehydrogenase gene from acetobacter suboxydans in escherichia coli].the partial genomic library of acetobacter suboxydans was constructed using yeast-e. coli shuttle plasmid yep352 as vector. two positive transformants, designated as dh5 alpha(pad91) and dh5 alpha(pad98), were obtained by screening the growth of transformants on the agar plate in which d-arabitol was used as the sole carbon source. the results of southern blot and restriction endonuclease analysis showed that the two recombinants are identical. the insert is about 2.3 kb. arabitol dehydrogenase ...200112549035
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 ...200212596856
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 ...200312619700
new developments in oxidative fermentation.oxidative fermentations have been well established for a long time, especially in vinegar and in l-sorbose production. recently, information on the enzyme systems involved in these oxidative fermentations has accumulated and new developments are possible based on these findings. we have recently isolated several thermotolerant acetic acid bacteria, which also seem to be useful for new developments in oxidative fermentation. two different types of membrane-bound enzymes, quinoproteins and flavopr ...200312664142
spoilage of bottled red wine by acetic acid bacteria.to determine the bacterial species associated with an outbreak of spoilage in commercially bottled red wine where the bottles had been stored in an upright vertical compared with horizontal position.200312680944
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