Publications

in vitro biosynthesis of acetan using electroporated acetobacter xylinum cells as enzyme preparations.	acetobacter xylinum strain nrrl b42 and its derivative rcgr1 produce a complex exopolysaccharide, acetan, containing glucose, mannose, glucuronic acid and rhamnose in a 4:1:1:1 molar ratio. the in vitro synthesis of acetan, employing electroporated cells as the enzyme system and the respective 14c-labelled sugar nucleotide precursors, is described. the synthesis of the prenyl-linked heptasaccharide repeat unit, already observed in edta-treated cells, was confirmed, as well as the formation of ot ...	1993	8277256
a new gene required for cellulose production and a gene encoding cellulolytic activity in acetobacter xylinum are colocalized with the bcs operon.	recently, it was shown that a cellulose-negative mutant (cel1) of acetobacter xylinum atcc 23769 carried an insertion of an indigenous transposable element (is1031a) about 500 bp upstream of the bcs operon, required for cellulose synthesis. here we show that cel1 can be complemented by wild-type dna covering the insertion point. nucleotide sequencing of this region revealed the presence of two open reading frames, orf1 and orf2. orf2, which is disrupted by the is1031a insertion in cel1, potentia ...	1994	8300521
bacillus subtilis gtab encodes udp-glucose pyrophosphorylase and is controlled by stationary-phase transcription factor sigma b.	transcription factor sigma b of bacillus subtilis controls a large stationary-phase regulon, but in no case has the physiological function of any gene in this regulon been identified. here we show that transcription of gtab is partly dependent on sigma b in vivo and that gtab encodes udp-glucose pyrophosphorylase. the gtab reading frame was initially identified by a sigma b-dependent tn917lacz fusion, csb42. we cloned the region surrounding the csb42 insertion, identified the reading frame conta ...	1993	8320212
triggering of cellulase biosynthesis by cellulose in trichoderma reesei. involvement of a constitutive, sophorose-inducible, glucose-inhibited beta-diglucoside permease.	we prepared [u-14c]cellobiose by cultivating acetobacter pasteurianus in the presence of [u-14c]glucose and hydrolyzing the [u-14c]cellulose formed with beta-glucosidase-free cellulase from trichoderma reesei. this 14c-labeled cellobiose was used to investigate the presence of an uptake system for cellobiose in t. reesei. evidence was obtained for the presence of a high affinity (km for cellobiose 0.3 microm) but low activity (2.5 milliunits/mg fungal dry weight) cellobiose permease. the permeas ...	1993	8366083
structural studies of acetan, an exopolysaccharide elaborated by acetobacter xylinum.	the exopolysaccharide acetan, elaborated by acetobacter xylinum, has been investigated. the polysaccharide and a heptasaccharide, obtained on enzymic hydrolysis, corresponding to the repeating unit were characterised by sugar and methylation analysis and by nmr spectroscopy and ms. it is concluded that the polysaccharide is composed of repeating units with the following structure. [formula: see text] the polysaccharide further contains approximately two o-acetyl groups per repeating unit, which ...	1993	8370027
phage acm1-mediated transduction in the facultatively methanol-utilizing acetobacter methanolicus mb 58/4.	phage acm1, generally virulent for the acidophilic facultatively methanol-utilizing strain of acetobacter methanolicus mb 58/4, is also capable of lysogenizing its host strain at a low rate. using amino acid-auxotrophic mutants of a. methanolicus mb 58/4 as recipient strains, transduction of his, leu and tyr markers could be demonstrated in this system. the ability to prepare transducing lysates by propagation of phage acm1 on the prototrophic donor strain a. methanolicus mb 58/4, the transducti ...	1993	8376955
a novel quinoprotein methanol dehydrogenase containing an additional 32-kilodalton peptide purified from acetobacter methanolicus: identification of the peptide as a moxj product.	acetobacter methanolicus is a unique acetic acid bacterium which has a methanol oxidase respiratory chain in addition to an ethanol oxidase respiratory chain. in this study, two different forms of methanol dehydrogenase (type i and ii mdhs) were purified from a. methanolicus grown on methanol. type i mdh was more basic (pi of 8.0) and smaller (m(r) of 148k) than type ii mdh (pi of 6.7 and m(r) of 177k). type i mdh consisted of alpha and beta subunits of 62 and 10 kda, which has the same alpha 2 ...	1993	8389187
the bradyrhizobium japonicum serocluster 123 hyperreiterated dna region, hrs1, has dna and amino acid sequence homology to is1380, an insertion sequence from acetobacter pasteurianus.	we have sequenced and analyzed the hyperreiterated dna region, hrs1, from bradyrhizobium japonicum usda 424. the 2.1-kb hrs1 fragment is closely linked to the b. japonicum common and genotype-specific nodulation genes in serogroup 123 and 127 strains. southern hybridization analyses indicated that one copy of hrs1 is also located next to the fixrnifa locus in b. japonicum usda 424. nucleotide sequence analysis revealed the presence of a 4-bp target site duplication in hrs1 which is identical to ...	1993	8390818
characterization of a cytochrome a1 that functions as a ubiquinol oxidase in acetobacter aceti.	the terminal oxidase for ethanol oxidation in acetobacter aceti was purified as a complex consisting of four subunits (subunits i, ii, iii, and iv) with molecular masses of 72, 34, 21, and 13 kda, respectively. spectrophotometric analysis and catalytic properties determined with the purified enzyme showed that it belonged to a family of cytochrome a1 (ba)-type ubiquinol oxidases. a polymerase chain reaction with two oligonucleotides designed for amino acid sequences that are conserved in subunit ...	1993	8392509
chirality of amino acids of microorganisms used in food biotechnology.	bacteria of the genera acetobacter, bifidobacterium, brevibacterium, lactobacillus, micrococcus, propionibacterium, and streptococcus, which are used as so-called starter cultures for the large-scale production of fermented foods and beverages in food biotechnology, have been investigated for the chirality of their amino acids (aa) by gas chromatography (gc). bacteria were grown in complex media, centrifuged, and washed with 0.85% aqueous nacl. aliquots were totally hydrolyzed (6 m hcl, 110 degr ...	1993	8398596
a family of is1031 elements in the genome of acetobacter xylinum: nucleotide sequences and strain distribution.	an insertion sequence (here called is1031a) from acetobacter xylinum atcc 23769 has recently been isolated. this study describes the complete nucleotide sequence of is1031a as well as the sequences of two novel iso-is1031 elements, is1031c and is1031d, from a. xylinum atcc 23769. the three iss are all exactly 930 bp long, have imperfect terminal inverted repeats of 24 bp for is1031a and 21 bp for is1031c and is1031d, are flanked by three base pair direct repeats, and contain an open reading fram ...	1993	8412666
characterization of a variant of the polysaccharide acetan produced by a mutant of acetobacter xylinum strain cr1/4.	acetobacter xylinum nrrl b42 (ncib 40123) produces both cellulose and a complex anionic branched heteropolysaccharide called acetan. chemical mutagenesis was used to isolate stable cellulose-minus acetobacter xylinum mutants. further chemical mutagenesis of these cellulose-minus a. xylinum bacteria was used to select mutants which secrete polysaccharides which are variants of the acetan structure. preparation, purification and characterization of these polysaccharides are described. methylation ...	1993	8444650
characterization of the replicon from plasmid pac1 from acetobacter pasteurianus.	a panel of recombinant plasmids pack5 and pact7 was prepared by introducing kanamycin and tetracycline resistance into the partially split plasmid pac1 which contained replicon isolated from acetobacter pasteurianus. the replicon in plasmid pac1 is compatible with the cole1 replicon. compared to pbr322, the plasmid had more than 30 copies per chromosome in escherichia coli cells. plasmids were transformed into e. coli dh1, acetobacter pasteurianus 3614, acetobacter aceti 3620, shigella, citrobac ...	1993	8447828
some properties of restriction endonuclease apabi from acetobacter pasteurianus.	a new site-specific endonuclease has been isolated from acetobacter pasteurianus and has been named apabi. the enzyme recognizes 35 cleavage sites on bacteriophage lambda dna, 20 sites on adenovirus-2 dna and 2 sites on plasmid pbr322. the recognition sequence for this enzyme is 3'-cgt/nnnnnacg-5' 5'-gcannnnn/tgc-3'.	1993	8457597
zymomonas mobilis--science and industrial application.	zymomonas mobilis is undoubtedly one of the most unique bacterium within the microbial world. known since 1912 under the names termobacterium mobilis, pseudomonas linderi, and zymomonas mobilis, reviews on its uniqueness have been published in 1977 and 1988. the bacterium zymomonas mobilis not only exhibits an extraordinarily uniqueness in its biochemistry, but also in its growth behavior, energy production, and response to culture conditions, as well as cultivation techniques used. this uniquen ...	1993	8477453
hemicelluloses as structure regulators in the aggregation of native cellulose.	the influence of hemicelluloses on the aggregation of cellulose in higher plant cell walls was modelled by adding hemicelluloses to cultures of the cellulose producer acetobacter xylinum. characterization of the celluloses by x-ray diffractometry showed them to be more like those that occur in higher plants; the coaggregation of the hemicelluloses suggests their occlusion within and between the crystalline domains of the celluloses. the authors propose that hemicelluloses may be primary moderato ...	1993	8485102
cloning and sequencing the reca+ genes of acetobacter polyoxogenes and acetobacter aceti: construction of reca- mutants of by transformation-mediated gene replacement.	the reca+ gene of acetobacter polyoxogenes was cloned as a gene that conferred methyl methanesulfonate resistance (mmsr) on the reca- escherichia coli hb101. the cloned reca+ gene also conferred (i) resistance to uv irradiation, (ii) enhanced intrachromosomal recombination, and (iii) permitted prophage phi 80 induction in e. coli reca- lysogens. nucleotide sequence determination revealed that the reca product consists of 348 amino acids (aa) corresponding to 38 kda, and shows significant similar ...	1993	8486287
the yeast spectrum of the 'tea fungus kombucha'.	the tea fungus 'kombucha' is a symbiosis of acetobacter, including acetobacter xylinum as a characteristic species, and various yeasts. a characteristic yeast species or genus has not yet been identified. kombucha is mainly cultivated in sugared black tea to produce a slightly acidulous effervescent beverage that is said to have several curative effects. in addition to sugar, the beverage contains small amounts of alcohol and various acids, including acetic acid, gluconic acid and lactic acid, a ...	1995	8559192
function of multiple heme c moieties in intramolecular electron transport and ubiquinone reduction in the quinohemoprotein alcohol dehydrogenase-cytochrome c complex of gluconobacter suboxydans.	alcohol dehydrogenase (adh) of acetic acid bacteria functions as the primary dehydrogenase of the ethanol oxidase respiratory chain, where it donates electrons to ubiquinone. adh is a membrane-bound quinohemoprotein-cytochrome c complex which consists of subunits i (78 kda), ii (48 kda), and iii (14 kda) and contains several hemes c as well as pyrroloquinoline quinone as prosthetic groups. to understand the role of the heme c moieties in the intramolecular electron transport and the ubiquinone r ...	1996	8617755
molecular characterization of the levansucrase gene from the endophytic sugarcane bacterium acetobacter diazotrophicus srt4.	the acetobacter diazotrophicus srt4 gene encoding levansucrase (ec 2.4.1.10) (isda) was isolated from a genomic library. the nucleotide sequence of a 2.3 kb dna fragment sufficient for complementation of a levansucrase-deficient mutant (obtained by ems treatment) was determined. the isda gene (1751 bp) coded for a polypeptide of molecular mass 64.9 kda with an isoelectric point of 5.2. the n-terminal amino acid sequence of the extracellular levansucrase indicated the presence of a precursor prot ...	1996	8704949
mass spectrometric studies of the thermal decomposition of carbohydrates using 13c-labeled cellulose and glucose.	the mechanism of the thermal decomposition of carbohydrates is very important to the development of fuels, fibers, and paper products. to help gain more insight into the pyrolysis chemistry of cellulose, we have carried out experimental studies using acetobacter xylinum cellulose grown on d-(1-13c)-glucose medium with incorporation levels of 1-13c of 14%, as determined by 13c nmr analysis. samples of the labeled cellulose, as well as d-(1-13c)- and d-(2-13c)-glucose, were pyrolyzed under fast-he ...	1996	8721146
16s-23s ribosomal rna spacer regions of acetobacter europaeus and a. xylinum, trna genes and antitermination sequences.	the 16s-23s ribosomal rna spacer regions of acetobacter europaeus dsm 6160, a. xylinum ncib 11664 and a. xylinum cl27 were amplified by pcr. specific pcr products were obtained from each strain and their nucleotide sequences determined. the spacer region of a. europaeus comprises 768 nucleotides (nt), that of a. xylinum 778 nt and that of a. xylinum cl27 759 nt. genes encoding trnaile and trnaala were identified. putative antitermination sequences were found between the trnaala sequence and the ...	1996	8759788
isolation and nucleotide sequence of the gdp-mannose:cellobiosyl-diphosphopolyprenol alpha-mannosyltransferase gene from acetobacter xylinum.	a genetic locus from acetobacter xylinum involved in acetan polysaccharide synthesis has been characterized. the chromosomal region was identified by screening a genomic library of a. xylinum in a xanthomonas campestris mutant defective in xanthan polysaccharide synthesis. the a. xylinum cosmid clone can functionally complement a xanthan-negative mutant. the polymer produced by the recombinant strain was found to be indistinguishable from xanthan. insertion mutagenesis and subcloning of the cosm ...	1996	8759843
analysis of 76 kb of the chlorella virus pbcv-1 330-kb genome: map positions 182 to 258.	analysis of 76 kb of newly sequenced dna, located between map positions 182 and 258 kb in the 330-kb chlorella virus pbcv-1 genome, revealed 175 open reading frames (orfs) of 65 codons or longer. one hundred and five of these 175 orfs were considered major orfs. twenty-one of the 105 major orfs resembled proteins in databases including ribonucleotide reductase small subunit, rnase iii, thioredoxin, glutaredoxin, protein disulfide isomerase, deoxynucleoside kinase, frog virus 3 atpase, acetobacte ...	1996	8806566
sequence-specific dna modification in acetobacter xylinum.	two cryptic plasmids have been discovered in acetobacter xylinum b42 and in its derivative pea-1, a cellulose defective mutant. these two plasmids were designated pax1 and pax2 (50 and 105 kb in size, respectively). a restriction map was constructed for pax1. attempts to cure these plasmids were unsuccessful. enzyme restriction analysis showed that these plasmids contain protected ecori and apoi sites. using southern blot and hybridization techniques, the protection was extended to chromosomal d ...	1996	8832107
production of cellulose ii by acetobacter xylinum in the presence of 2,6-dichlorobenzonitrile.	this report provides x-ray diffraction and raman spectral evidence that, when 2,6-dichlorobenzonitrile is present in the culture medium, acetobacter xylinum, which is a model system for investigation of the biosynthesis of native cellulose, produces cellulose ii, as well as cellulose i. the significance of the observations with respect to the mechanism of biosynthesis of cellulose is discussed briefly.	1996	8842778
physicochemical studies on xylinan (acetan). i. characterization by gel permeation chromatography on sepharose cl-2b coupled with static light scattering and viscometry.	laboratory-made samples of the polysaccharide xylinan (acetan) were fractionated on sepharose cl-2b using 0.1m nacl as eluant. the weight average molar masses and intrinsic viscosities were estimated in the fractions by multiangle laser light scattering (off-line) and capillary viscometry, respectively. the mark-houwink-sakurada plot was found to be indicative of semiflexible coils (a = 0.90). the angular dependence of scattered light was interpreted by fitting with theoretically calculated "mas ...	1996	8875824
higher plants contain homologs of the bacterial cela genes encoding the catalytic subunit of cellulose synthase.	in spite of much effort, no one has succeeded in isolating and characterizing the enzyme(s) responsible for synthesis of cellulose, the major cell wall polymer of plants. we have characterized two cotton (gossypium hirsutum) cdna clones and identified one rice (oryza sativa) cdna that are homologs of the bacterial cela genes that encode the catalytic subunit of cellulose synthase. three regions in the deduced amino acid sequences of the plant cela gene products are conserved with respect to the ...	1996	8901635
identification, cloning and sequencing the acea gene involved in acetan biosynthesis in acetobacter xylinum.	the acea gene from acetobacter xylinum was identified and cloned from a genomic dna library. the complete dna sequence was determined and computer analysis of the translated gene sequence revealed homology with the deduced amino acid sequence of gumd from xanthomonas campestris. therefore acea is likely to encode the phosphate-prenyl glucose l-phosphate transferase catalyzing the first step in acetan biosynthesis in a. xylinum.	1996	8935665
identification of structural genes involved in bacterial exopolysaccharide production.		1996	8948107
cloning and nucleotide sequence of apali restriction-modification system from acetobacter pasteurianus ifo 13753.	the apali restriction-modification system from acetobacter pasteurianus ifo 13753 recognizes the nucleotide sequence gtgcac. the gene coding for the apali methylase (m.apali) was cloned into escherichia coli dh5 alpha mcr, and the nucleotide sequence of the gene was analyzed. the m.apali gene coded for a protein of 429 amino acid residues (molecular mass, 46,554 daltons). the apali restriction endonuclease (r.apali) gene was analyzed by inverse polymerase chain reaction. the r.apali gene coded f ...	1996	8987585
genetic analysis of the acetan biosynthetic pathway in acetobacter xylinum: nucleotide sequence analysis of the aceb, acec, aced and acee genes.	sequence analysis of a 5.323 kb chromosomal dna fragment from acetobacter xylinum involved in the biosynthesis of the exopolysaccharide acetan, revealed the presence of four ace genes designated aceb, acec, aced and acee. comparison of translated gene sequences to the databanks was used to assign putative gene functions. aceb displayed strong homology to a glucose-diphosphoprenyl beta, d-glucose transferase from xanthomonas campestris, while acec was homologous to a cellobiosyl-diphosphoprenyl a ...	1996	8988363
purification and properties of citrate synthase from acetobacter europaeus.	citrate synthase (ec 4.1.3.7) was purified from the acidophilic bacterium acetobacter europaeus to electrophoretic homogeneity. the specific activity was 228 units/mg of protein during the exponential ethanol-oxidation growth phase. the enzyme has a molecular mass of 280 kda and is a hexamer with a subunit size of 46 kda. the apparent k(m) values were 20 microm for oxaloacetate and 51 microm for acetyl-coa. unlike citrate synthase from other gram-negative bacteria, the activity of the enzyme was ...	1997	8997706
construction and use of a versatile set of broad-host-range cloning and expression vectors based on the rk2 replicon.	the plasmid vectors described in this report are derived from the broad-host-range rk2 replicon and can be maintained in many gram-negative bacterial species. the complete nucleotide sequences of all of the cloning and expression vectors are known. important characteristics of the cloning vectors are as follows: a size range of 4.8 to 7.1 kb, unique cloning sites, different antibiotic resistance markers for selection of plasmid-containing cells, orit-mediated conjugative plasmid transfer, plasmi ...	1997	9023917
cloning and expression of aatii restriction-modification system in escherichia coli.	the genes encoding the aatii restriction endonuclease and methylase from acetobacter aceti have been cloned and expressed in escherichia coli. the nucleotide sequences of aatiim and aatiir genes were determined. the aatiim and aatiir genes are 996 bp and 1038 bp, respectively, encoding the 331-aa methylase with a predicted molecular mass of 36.9 kda, and the 345-aa aatii restriction endonuclease with a predicted molecular mass of 38.9 kda. the two genes overlap by 4 base pairs and are transcribe ...	1997	9034320
a new insertion sequence is1452 from acetobacter pasteurianus.	a new insertion sequence element, is1452, was found to be associated with inactivation of the alcohol dehydrogenase by insertion in the adhs gene encoding subunit iii of the three-component membrane-bound alcohol dehydrogenase complex in acetobacter pasteurianus. cloning and sequencing analyses of the mutated subunit iii gene locus revealed that is1452 was inserted at or near the ribosome-binding sequence of adhs. analysis of transcription using the chloramphenicol acetyltransferase gene as the ...	1997	9043130
characterization of the genes encoding the three-component membrane-bound alcohol dehydrogenase from gluconobacter suboxydans and their expression in acetobacter pasteurianus.	the three-component membrane-bound alcohol dehydrogenase (adh) of gluconobacter suboxydans ifo12528 was purified, and the nh2-terminal amino acid sequence of each subunit was determined. on the basis of the amino acid sequences, the genes adha, encoding the 72-kda dehydrogenase, adhb, encoding the 44-kda cytochrome c-553 (a co-binding cytochrome c), and adhs, encoding a 15-kda protein, were cloned and the amino acid sequences of their products were deduced from the nucleotide sequences. the dehy ...	1997	9055427
characterization of an insertion sequence, is12528, from gluconobacter suboxydans.	a novel insertion sequence element, is12528, was found to be associated with inactivation of the alcohol dehydrogenase by insertion in the adha gene, which encodes the primary dehydrogenase subunit of the three-component membrane-bound alcohol dehydrogenase complex in gluconobacter suboxydans. cloning and sequencing analyses revealed that is12528 was 905 bp in length and had a terminal inverted repeat of 18 bp. in addition, is12528 was found to generate a 3-bp duplication (tma, where m represent ...	1997	9055428
effect of acetic acid bacterium on ethanol oxidation in vivo.	we investigated the possible effects of acetic acid bacterium on ethanol oxidation in vivo by monitoring the blood ethanol level after injecting 5% ethanol with (treated group) or without (control group) a freeze-dried bacterial cell suspension directly into the stomach of anesthesized rats. paired comparison t-tests of the results indicate that the blood ethanol concentration of the rats in the treated group was significantly (p < 0.07) lower than that in the control group. when measured 10 min ...	1997	9058979
structure of the repeating oligosaccharide from the lipopolysaccharide of the nitrogen-fixing bacterium acetobacter diazotrophicus strain pal 5.	acetobacter diazotrophicus is an acid-tolerant nitrogen-fixing bacterium found in roots, rhizosphere, stems, and leaves of sugar cane (saccharum officinarum) cultivated in brazil. the o-polysaccharide from the lipopolysaccharide of the root isolate strain pal 5 has been determined by a combination of methylation analysis and two-dimensional high field nmr spectroscopy. the pentasaccharide repeat has the structure: [formula: see text] minor resonances in the nmr spectra are consistent with the pr ...	1997	9098959
endo-beta-glucanase from acetobacter xylinum: purification andcharacterization	a cellulose-producing acetic acid bacterium,acetobacter xylinum ku-1, abundantly produces an extracellularendo-beta-glucanase (ec 3.2.1.4) in the culture broth. the enzyme was purifiedto homogeneity by deae- and cm- toyopearl 650m ion-exchange chromatography,butyl-toyopearl 650m hydrophobic chromatography, and toyopearl hw-50 gelfiltration. the purified enzyme showed the maximum activity at ph 5 and50°c: it was stable up to 50°c at ph 5, activated by co2+, andcompetitively inhibited by h ...	1997	9099632
the toxicity of substituted phenolic compounds to a detoxifying and an acetic acid bacterium.	in the detoxifying bacterium acinetobacter calcoaceticus 69-v and in the acetic acid bacterium acetobacter methanolicus mb 58, glucose and xylose are oxidized, respectively, via pqq-dependent membrane-bound dehydrogenases, which are linked to the respiratory chain in a manner enabling energy conservation via electron transport phosphorylation (etp) in the cytoplasmic membrane. neither the glucose and gluconic acid nor the xylose and xylonic acid are metabolized. therefore, measurements of sugar ...	1997	9143455
cloning and sequence analysis of a novel insertion element from plasmids harbored by the carbofuran-degrading bacterium, sphingomonas sp. cfo6.	sphingomonas sp. cfo6 (a member of the alpha group of proteobacteria) was isolated from a washington soil by enrichment on the insecticide carbofuran as a sole source of carbon and energy. this strain has been shown to harbor five plasmids, at least some of which are required for catabolism of carbofuran. rearrangements, deletions, and loss of individual plasmids resulting in the loss of the carbofuran-degrading phenotype were observed following treatment with heat or introduction of tn5. severa ...	1997	9200220
controlled secretion into the culture medium of a hybrid beta-glucanase by acetobacter methanolicus mediated by the kil gene of escherichia coli located on a tn5-derived transposon.	a tn5-based transposon bearing the kil gene (killing protein), mediating controlled export of periplasmic proteins into the culture medium, was constructed (tn5-kil3). this transposon contained the kil gene of the colel plasmid under the growth-phase-dependent promoter of the fic gene (filamentation induced by camp) of escherichia coli, an interposon located upstream of kil, a kanamycin/neomycin-resistance gene, a multiple cloning site and the mob site. the transposition of tn5-kil3 to acetobact ...	1997	9210342
influence of substituent of direct dye having bisphenylenebis(azo) skeletal structure on structure of nascent cellulose produced by acetobacter xylinum [i]: different influence of direct red 28, blue 1 and 15 on nascent structure.	the difference of influence of a certain kind of direct dye on the structure of nascent microbial cellulose was examined, with direct red 28 have a biphenylenebis(azo) skeletal structure; direct blue 1 having two hydroxyl, two methoxy and two sulfonate groups more than direct red 28; and direct blue 15 whose sulfonate groups position are different compared to direct blue 1. it became clear that the product in the presence of a direct dye (in particular, direct red 28) has the structure in which ...	1997	9218171
biochemical and genetic characterization of the acetaldehyde dehydrogenase complex from acetobacter europaeus.	the aldehyde dehydrogenase complex, which catalyzes the oxidation of acetaldehyde to acetic acid, was purified to apparent homogeneity from the membrane fraction of the industrial vinegar-producing strain acetobacter europaeus. the determined km for acetaldehyde was 2.1 mm. sds-page of the enzyme complex showed the presence of three different subunits with molecular masses of 79, 46, and 17 kda, respectively. the two larger subunits contained heme. the difference spectrum indicated a cytochrome ...	1997	9238099
improved broad-host-range rk2 vectors useful for high and low regulated gene expression levels in gram-negative bacteria.	this report describes the construction and use of improved broad-host-range expression vectors based on the previously constructed pjb137 and pjb653 plasmids (blatny et al., 1997). these vectors contain the minimal replicon of rk2 and the inducible pu or pm promoters together with their regulatory xylr or xyls genes, respectively, from the pseudomonas putida tol plasmid pwwo. a set of atg vectors were derived from pjb653, and these vectors are characterized by the relatively small size, the pres ...	1997	9281494
coffea arabica l., a new host plant for acetobacter diazotrophicus, and isolation of other nitrogen-fixing acetobacteria.	acetobacter diazotrophicus was isolated from coffee plant tissues and from rhizosphere soils. isolation frequencies ranged from 15 to 40% and were dependent on soil ph. attempts to isolate this bacterial species from coffee fruit, from inside vesicular-arbuscular mycorrhizal fungi spores, or from mealybugs (planococcus citri) associated with coffee plants were not successful. other acid-producing diazotrophic bacteria were recovered with frequencies of 20% from the coffee rhizosphere. these n2-f ...	1997	9293018
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
characterization of microbial cellulose from a high-producing mutagenized acetobacter pasteurianus strain.	a wild-type acetobacter pasteurianus was subjected to chemical mutagenesis for the induction and isolation of a cellulose overproducing strain. a mutagenized strain capable of synthesizing double amounts of cellulose compared to the wild type was obtained. cellulose, both from the wild-type and the mutagenized strain, was extracted and purified for chemical characterization and investigation of its physico-chemical properties. the comparison of the two microbial polysaccharides shows that the pu ...	1997	9305792
cloning of the acef gene encoding the phosphomannose isomerase and gdp-mannose pyrophosphorylase activities involved in acetan biosynthesis in acetobacter xylinum.	the acef gene from acetobacter xylinum was identified and cloned from a genomic dna library. the complete dna sequence was determined and computer analysis of the translated gene sequence revealed homology with the deduced amino acid sequence of xanb from xanthomonas campestris. therefore acef is likely to encode a bifunctional enzyme with mannose-6-phosphate isomerase (pmi) and gdp-mannose pyrophosphorylase (gmp) activities. pmi and gmp activities were detected in strains of escherichia coli ex ...	1997	9311139
resonance raman, infrared, and epr investigation on the binuclear site structure of the heme-copper ubiquinol oxidases from acetobacter aceti: effect of the heme peripheral formyl group substitution.	acetobacter aceti produces two different terminal ubiquinol oxidases (cytochromes a1 and o) depending on the culture conditions. two types of oxidases share a common protein moiety but with different heme components at the binuclear center (heme a for cytochrome a1 and heme o for cytochrome o). we investigated the structure of the binuclear site of the two oxidases using resonance raman, fourier transform-infrared (ft-ir), and epr spectroscopies to clarify the interactions of heme a formyl group ...	1997	9335565
acetate-specific stress response in acetate-resistant bacteria: an analysis of protein patterns.	many metabolic byproducts have toxic effects on bacteria, and acetic acid is an excellent model for such molecules. the negative effects of acetate, which include decreased growth rates and specific productivities, appear for escherichia coli at acetate concentrations lower than 5 g/l. acetic acid bacteria, however, are naturally resistant to the detrimental effects of acetate in their surroundings; they remain active at acetate levels well over 40 g/l. this study investigated the response to ac ...	1997	9336975
studies on recombinant acetobacter xylinum alpha-phosphoglucomutase.	the phosphoglucomutase (pgm) from acetobacter xylinum, which had been cloned and expressed in escherichia coli, has been studied. after expression, the enzyme was purified from the e. coli in a three-step process consisting of (nh4)2so4 precipitation, gel filtration and anion-exchange chromatography. the purified enzyme gave one band on gel electrophoresis and was judged essentially free of impurities, although it was unstable when diluted without the addition of 15 microm bsa. the isoelectric p ...	1997	9337869
sequence analysis of a 1296-nucleotide plasmid from xylella fastidiosa.	a cryptic plasmid from xylella fastidiosa strain atcc 35868 was cloned, sequenced, and the sequence entered into genbank (u71220). the plasmid is 1296 nucleotides in length with 55% gc content and three open reading frames. a plasmid with sequence homology was found in only one other strain of x. fastidiosa, atcc 35878. searches of the genbank reveal nucleotide sequence homology with plasmid pnkh43 from stenotrophomonas maltophilia, and amino acid sequence homology with phage pf3 from pseudomona ...	1997	9351204
a beta-glucosidase gene downstream of the cellulose synthase operon in cellulose-producing acetobacter.	an open reading frame was found 214 bp downstream of the cellulose synthase operon of acetobacter. the encoded amino acid sequence was found to be similar to some beta-glucosidases (g3ases). we detected g3ase activity in the culture medium and analysis of the n-terminal amino acid sequence showed that this gene encodes the enzyme. therefore, it is possible that this region is a gene cluster for cellulose synthesis.	1997	9362130
c-di-gmp-binding protein, a new factor regulating cellulose synthesis in acetobacter xylinum.	a protein which specifically binds cyclic diguanylic acid (c-di-gmp), the reversible allosteric activator of the membrane-bound cellulose synthase system of acetobacter xylinum, has been identified in membrane preparations of this organism. c-di-gmp binding is of high affinity (kd 20 nm), saturable and reversible. the equilibrium of the reaction is markedly and specifically shifted towards the binding direction by k+. the c-di-gmp binding protein, structurally associated with the cellulose synth ...	1997	9369216
a new insertion sequence from sinorhizobium meliloti with homology to is1357 from methylobacterium sp. and is1452 from acetobacter pasteurianus.	the insertion sequence isrm8 was identified by sequence analysis of the cryptic plasmid prmegr4b of sinorhizobium meliloti gr4. isrm8 is 1451 bp in length and carries 22/24-bp terminal imperfect inverted repeats with seven mismatches and a direct target site duplication of 3 bp. isrm8 carries a unique open reading frame whose putative protein showed significant similarity to the insertion sequences is1357 and is1452, isolated from methylobacterium sp. and acetobacter pasteurianus, respectively. ...	1998	9453160
a recipe for cellulose.		1998	9471727
nucleotide sequence of the nifh gene coding for nitrogen reductase in the acetic acid bacterium acetobacter diazotrophicus.	the nifh gene sequence of the nitrogen-fixing bacterium acetobacter diazotrophicus was determined with the use of the polymerase chain reaction and universal degenerate oligonucleotide primers. the gene shows highest pair-wise similarity to the nifh gene of azospirillum brasilense. the phylogenetic relationships of the nifh gene sequences were compared with those inferred from 16s rrna gene sequences. knowledge of the sequence of the nifh gene contributes to the growing database of nifh gene seq ...	1998	9489028
analysis of hopanoids in bacteria involved in food technology and food contamination.	hopanoids are pentacyclic triterpenoids which are believed to act as reinforcers of membranes in certain prokaryotic microorganisms. a rapid and sensitive method for their screening in bacteria was elaborated, involving extraction of nonsaponifiable lipids and the analysis by gas chromatography-mass spectrometry, selectively monitoring the ion of m/z = 191. using the method, hopanoids were detected in strains of acetobacter pasteurianus, but were found to be absent in lactic acid bacteria (lacto ...	1998	9503615
intramolecular electron transport in quinoprotein alcohol dehydrogenase of acetobacter methanolicus: a redox-titration study	quinohemoprotein-cytochrome c complex alcohol dehydrogenase (adh) of acetic acid bacteria consists of three subunits, of which subunit i contains pyrroloquinoline quinone (pqq) and heme c, and subunit ii contains three heme c components. the pqq and heme c components are believed to be involved in the intramolecular electron transfer from ethanol to ubiquinone. to study the intramolecular electron transfer in adh of acetobacter methanolicus, the redox potentials of heme c components were determi ...	1998	9526036
effect of deacetylation on the synergistic interaction of acetan with locust bean gum or konjac mannan.	it has been discovered that deacetylation of the bacterial polysaccharide acetan promotes synergistic interactions with either locust bean gum (lbg) or konjac mannan (km). acetan is similar in structure to xanthan, and adopts a similar 5-fold conformation in the solid state. like xanthan, it shows a thermally reversible order (helix)-disorder (coil) transition in solution. both polymers have a cellulosic backbone with charged (anionic) sidechains attached at o-3 of alternate glucosyl residues, b ...	1997	9534230
the production of a new water-soluble polysaccharide by acetobacter xylinum nci 1005 and its structural analysis by nmr spectroscopy.	a new water-soluble polysaccharide (wsp) was isolated from a culture of acetobacter xylinum nci 1005 grown on sucrose. the structure of the wsp was analysed by nuclear magnetic resonance spectroscopy and determined to be a beta-(2-->6)-linked polyfructan, which is structurally different from the polymer synthesized from glucose instead of sucrose by the same strain. the discovery of this new polysaccharide has revealed that the bacterium is able to synthesize two different kinds of water-soluble ...	1997	9534231
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
mapping the active sites of 3-phosphoglycerate kinase and glycerol kinase with monoammine chromium(iii) atp.	the 12 isomers of monoammine chromium(iii) atp have been used to probe the atp binding sites of yeast 3-phosphoglycerate kinase and glycerol kinase from candida mycoderma. inhibition studies of 3-phosphoglycerate kinase show a dramatic decrease in isomer binding only when the ammonia is in the delta axial facial anti position. this suggests an open site architecture with only one strong contact point between the coordination sphere and the enzyme surface. these results agree well with the comput ...	1998	9548916
identification of a novel triterpenoid saponin from pisum sativum as a specific inhibitor of the diguanylate cyclase of acetobacter xylinum.	a specific and highly potent inhibitor of diguanylate cyclase, the key regulatory enzyme of the cellulose synthesizing apparatus in the bacterium acetobacter xylinum, was isolated from extracts of etiolated pea shoots (pisum sativum). the inhibitor has been purified by a multistep procedure, and sufficient amounts of highly purified compound (3-8 mg) for spectral analysis were obtained. the structure of this compound was established as 3-o-alpha-l-rhamnopyranosyl-(1-->2)-beta-d-galactopyranosyl- ...	1998	9559560
life in grasses: diazotrophic endophytes.	n2-fixing bacteria such as azoarcus spp., herbaspirillum spp, and acetobacter diazotrophicus can infect the interior of gramineous plants without causing symptoms of plant disease but do not survive in soil. like phytopathogens, they can penetrate into central tissues and spread systemically. there is no evidence for an endosymbiosis in living plant cells; however, the bacteria are physiologically active in the plant apoplast.	1998	9587190
characterization of glycerol uptake and glycerol kinase activity in rat hepatocytes cultured under different hormonal conditions.	glycerol uptake and glycerol kinase activity were studied in primary cultures of rat hepatocytes in the presence of either 1 nm insulin, 1 nm glucagon, or 100 nm dexamethasone, alone or in combination in the culture medium. glycerol uptake exhibited saturation kinetic with k(m) values (microm) and vmax (nmol/min x mg protein) ranging from 250-402, and 7.9-10.1, respectively. the corresponding k(m) and vmax values for glycerol kinase activity were 36-46 and 8.7-12.7. using the metabolic uncoupler ...	1998	9606984
control of expression by the cellulose synthase (bcsa) promoter region from acetobacter xylinum bpr 2001.	the 5' upstream region (about 3.1kb) of the cellulose synthase operon (bcs operon) has been isolated by cloning from acetobacter xylinum strain bpr 2001. the expression level of the upstream region was determined using sucrose synthase cdna as a reporter gene in the shuttle vector psa19. the expression occurred with the 1.1-kb upstream sequence from the atg start codon of the bcs operon but not with the 241-bp upstream sequence in a. xylinum, although neither the 1.1-kb nor the 241-bp upstream s ...	1998	9630539
increased cellulose production from sucrose with reduced levan accumulation by an acetobacter strain harboring a recombinant plasmid.	cellulose production from sucrose by acetobacter strains is accompanied by the accumulation of a water-soluble polysaccharide, called levan. to improve cellulose productivity, a levansucrase-deficient mutant, ld-2, was derived from acetobacter strain 757 and used as a host for the construction of recombinant strains. an ld-2 mutant harboring a plasmid containing the sucrase gene, sucze3, from zymomonas mobilis together with zlis, a gene that encodes a secretion-activating factor under the contro ...	1998	9648211
preparation and preservation of freeze-dried cells of acetic acid bacteria with aldehyde oxidase activity.	freeze-dried cells of acetic acid bacteria were prepared to use as an additive for manufacturing and processing foods. when the freeze-dried cells were stored for 1 week at 5 degrees c, however, more than 50% of the original activity of aldehyde oxidase (aox) was lost. it was found that this decrease in aox was caused by damage to both the membrane-bound aldehyde dehydrogenase and terminal oxidase activities involved in the aldehyde oxidase electron transport system of acetic acid bacteria. the ...	1998	9692195
bacterial cellulose-binding domain modulates in vitro elongation of different plant cells	recombinant cellulose-binding domain (cbd) derived from the cellulolytic bacterium clostridium cellulovorans was found to modulate the elongation of different plant cells in vitro. in peach (prunus persica l.) pollen tubes, maximum elongation was observed at 50 &mgr;g ml-1 cbd. pollen tube staining with calcofluor showed a loss of crystallinity in the tip zone of cbd-treated pollen tubes. at low concentrations cbd enhanced elongation of arabidopsis roots. at high concentrations cbd dramatically ...	1998	9701575
three cdg operons control cellular turnover of cyclic di-gmp in acetobacter xylinum: genetic organization and occurrence of conserved domains in isoenzymes.	cyclic di-gmp (c-di-gmp) is the specific nucleotide regulator of beta-1,4-glucan (cellulose) synthase in acetobacter xylinum. the enzymes controlling turnover of c-di-gmp are diguanylate cyclase (dgc), which catalyzes its formation, and phosphodiesterase a (pdea), which catalyzes its degradation. following biochemical purification of dgc and pdea, genes encoding isoforms of these enzymes have been isolated and found to be located on three distinct yet highly homologous operons for cyclic diguany ...	1998	9721278
decolourization and biodegradation of n,n'-dimethyl-p-phenylenediamine by klebsiella pneumoniae rs-13 and acetobacter liquefaciens s-1.	klebsiella pneumoniae rs-13 and acetobacter liquefaciens s-1, both methyl red (mr)-degrading bacterial strains, degraded n,n'-dimethyl-p-phenylenediamine (dmpd) under aerobic conditions. dmpd, a toxic and mutagenic aromatic amine, is formed during the reductive cleavage of azo dyes such as mr. the effects of physical parameters, such as temperature and aeration, and chemical parameters, such as ph and concentrations of glucose, ethanol and ammonium sulphate in the culture medium, on the degradat ...	1998	9721658
description of acetobacter oboediens sp. nov. and acetobacter pomorum sp. nov., two new species isolated from industrial vinegar fermentations.	two strains of acetobacter sp., lth 2460t and lth 2458t, have been isolated from running red wine and cider vinegar fermentations, respectively. taxonomic characteristics of the isolates were investigated. comparative analysis of the 165 rrna sequences revealed > 99% similarity between strain lth 2460t and the type strains of the related species acetobacter europaeus and acetobacter xylinus and between strain lth 2458t and acetobacter pasteurianus. on the other hand, low levels of dna relatednes ...	1998	9734049
evidence for intermolecular binding between deacetylated acetan and the glucomannan konjac mannan.	binary mixtures of deacetylated acetan and konjac mannan form thermoreversible gels under conditions for which the individual components do not gel. such synergistic behaviour is normally attributed to intermolecular binding between the two polysaccharides. x-ray diffraction data obtained from oriented fibres prepared from deacetylated acetan-konjac mannan gels provides direct evidence for intermolecular binding between the two polysaccharides. the novel heterotypic junction zones appear to be s ...	1998	9764469
o-demethylase from ap6tobacterium dehalogenans--cloning, sequencing, and active expression of the gene encoding the corrinoid protein.	the ether-cleaving o-demethylase from the strictly anaerobic homoacetogen acetobacterium dehalogenans catalyses the methyltransfer from 4-hydroxy-3-methoxy-benzoate (vanillate) to tetrahydrofolate. in the first step a vanillate :corrinoid protein methyltransferase (methyltransferase i) mediates the methylation of a 25-kda corrinoid protein with the cofactor reduced to cob(i)alamin. the methyl group is then transferred to tetrahydrofolate by the action of a methylcorrinoid protein:tetrahydrofolat ...	1998	9826201
characterisation of the polysaccharide produced by acetobacter xylinum strain cr1/4 by light scattering and atomic force microscopy.	the molecular weight of the extracellular polysaccharide (cr1/4) produced by acetobacter xylinum strain cr1/4 has been shown to be dependent upon growth conditions. under normal growth conditions a high molecular weight polysaccharide ( > 1 x 10(6) da) is produced. maintaining the ph at 5 results in an order of magnitude increase in the total yield of polysaccharide, but also an order of magnitude decrease in molecular weight. analysis of the cr1/4 polysaccharides by the techniques of atomic for ...	1998	9849626
effect of high sugar concentration on nitrogenase activity of acetobacter diazotrophicus.	acetobacter diazotrophicus is a nitrogen-fixing bacterium that growth inside sugar cane plant tissue where the sucrose concentration is approximately 10%. the influence of high sugar content on nitrogenase was measured in the presence of oxygen and of nitrogen added in the form of ammonium and amino acids. in all parameters analyzed, 10% sucrose protected nitrogenase against inhibition by oxygen, ammonium, some amino acids, and also to some extent by salt stress. the oxygen concentration at whic ...	1998	9871014
enhancement of cellulose production by expression of sucrose synthase in acetobacter xylinum.	higher plants efficiently conserve energy atp in cellulose biosynthesis by expression of sucrose synthase, in which the high free energy between glucose and fructose in sucrose can be conserved and used for the synthesis of udp-glucose. a mixture of sucrose synthase and bacterial cellulose synthase proceeded to form udp-glucose from sucrose plus udp and to synthesize 1,4-beta-glucan from the sugar nucleotide. the mutant sucrose synthase, which mimics phosphorylated sucrose synthase, enhanced the ...	1999	9874763
the quinohemoprotein alcohol dehydrogenase of gluconobacter suboxydans has ubiquinol oxidation activity at a site different from the ubiquinone reduction site.	alcohol dehydrogenase (adh) of acetic acid bacteria functions as the primary dehydrogenase of the ethanol oxidase respiratory chain, where it donates electrons to ubiquinone. in addition to the reduction of ubiquinone, adhs of gluconobacter suboxydans and acetobacter aceti were shown to have a novel function in the oxidation of ubiquinol. the oxidation activity of ubiquinol was detected as an ubiquinol:ferricyanide oxidoreductase activity, which can be monitored by selected wavelength pairs at 2 ...	1999	9878716
substitution of asp-309 by asn in the arg-asp-pro (rdp) motif of acetobacter diazotrophicus levansucrase affects sucrose hydrolysis, but not enzyme specificity.	beta-fructofuranosidases share a conserved aspartic acid-containing motif (arg-asp-pro; rdp) which is absent from alpha-glucopyranosidases. the role of asp-309 located in the rdp motif of levansucrase (ec 2.4.1.10) from acetobacter diazotrophicus srt4 was studied by site-directed mutagenesis. substitution of asp-309 by asn did not affect enzyme secretion. the kcat of the mutant levansucrase was reduced 75-fold, but its km was similar to that of the wild-type enzyme, indicating that asp-309 plays ...	1999	9895294
phylogenetic identification of two major nitrogen-fixing bacteria associated with sugarcane.	acetobacter diazotrophicus and herbaspirillum seropedicae were identified by genetic methods based on 16s rrna sequences. a specific pcr method in combination with probing was developed for a. diazotrophicus. the pcr system includes four primers, of which the primers named ac (ctgtttcccgcaagggac) and di (gcgccccattgctgggtt) generated an 445 bp amplicon in all of the 11 a. diazotrophicus strains tested. the phylogenetic position of h. seropedicae was determined. h. seropedicae forms with oxalobac ...	1998	9924818
evidence that a beta-1,4-endoglucanase secreted by acetobacter xylinum plays an essential role for the formation of cellulose fiber.	cellulose-producing acetobacter xylinum has been known to secrete a cellulose-hydrolyzing beta-1,4-endoglucanase (cmcax). when antibodies to recombinant cmcax were added to the culture medium, the formation of cellulose fiber was severely inhibited. western blot analysis using the antibody showed that this enzyme was secreted into the medium even by a cellulose non-producing strain (cel-). these results indicate that beta-1,4-endoglucanase in the medium plays a critical role in the formation of ...	1998	9972249
[testing the osmotic-diffusion properties for the membranous dressing bioprocess].	in order to determine of the osmotic-diffusive properties of membranous dressing bioprocess, which is a microfibrous network of homogeneous cellulose produced in biosynthesis by acetobacter, the hydraulic permeability (lp), reflection (sigma) and diffusive permeability (omega) coefficients were measured. the values of these coefficients showed that this membrane possess a low selectivity. this amount it easy permeable for solvent (water) as well as for solutions (aqueous solutions of glucose, su ...	1998	10093152
wine vinegar production using a noncommercial 100-litre bubble column reactor equipped with a novel type of dynamic sparger	this paper describes batch and semicontinuous acetic acid fermentations for wine vinegar production carried out with acetobacter pasteurianus, and an industrial strain using a noncommercial 100-l bubble column reactor equipped with a novel type of gas-liquid dynamic sparger. results showed acetification rates with this fermentor (i.e., an overall acetic acid productivity of 1. 8 g/l/h and yield of 94%) similar to that of the frings acetator and higher as compared to others fermentors in current ...	1999	10099590
cloning of the escherichia coli endo-1,4-d-glucanase gene and identification of its product.	a plasmid (pyp17) containing a genomic dna insert from escherichia coli k-12 that confers the ability to hydrolyze carboxymethylcellulose (cmc) was isolated from a genomic library constructed in the cosmid vector plafr3 in e. coli dh5alpha. a small 1.65-kb fragment, designated bcsc (pyp300), was sequenced and found to contain an orf of 1,104 bp encoding a protein of 368 amino acid residues, with a calculated molecular weight of 41,700 da. bcsc carries a typical prokaryotic signal peptide of 21 a ...	1999	10102357
structural characterization of acetobacter diazotropicus levansucrase by matrix-assisted laser desorption/ionization mass spectrometry: identification of an n-terminal blocking group and a free-thiol cysteine residue.	high-resolution matrix-assisted laser desorption/ionization time-of-flight mass spectrometry was used to characterize the primary structure of the levansucrase (ec 2.4.1.10) secreted by acetobacter diazotropicus srt4. the technique permitted not only the reading frame of this enzyme, the amino acid sequence of which was deduced from dna, but also the elucidation of an n-terminal blocking group and the position of a disulfide bridge between cys309 and cys365 among the three cys residues. a free c ...	1999	10214721
digestion of crystalline cellulose substrates by the clostridium thermocellum cellulosome: structural and morphological aspects.	the action of cellulosomes from clostridium thermocellum on model cellulose microfibrils from acetobacter xylinum and cellulose microcrystals from valonia ventricosa was investigated. the biodegradation of these substrates was followed by transmission electron microscopy, fourier-transform ir spectroscopy and x-ray diffraction analysis, as a function of the extent of degradation. the cellulosomes were very effective in catalysing the complete digestion of bacterial cellulose, but the total degra ...	1999	10359670
cloning of cellulose synthase genes from acetobacter xylinum jcm 7664: implication of a novel set of cellulose synthase genes.	three sets of cellulose synthase genes were cloned from a cellulose-producing bacterium acetobacter xylinum jcm 7664. one set of genes (bcsai/bcsbi/bcsci/bcsdi) were highly conserved with the well-established type i genes in other strains of a. xylinum, while the other two (bcsabii-a, bcsabii-b) were homologous to the known type ii (acsaii). unexpectedly, they were immediately followed by a gene cluster of bcsx/bcsy/bcscii/orf569, likely forming an operon. western blotting demonstrated that the ...	1999	10382968
purification and enzymic properties of the fructosyltransferase of streptococcus salivarius atcc 25975.	the recombinant fructosyltransferase (ftf) of streptococcus salivarius was expressed in escherichia coli and purified to electrophoretic homogeneity after a combination of adsorption, ion-exchange and gel-filtration chromatography. the n-terminal signal sequence of the ftf was removed by e. coli at the same site as in its natural host. the purified ftf exhibited maximum activity at ph 6.0 and 37 degrees c, was activated by ca2+, but inhibited by the metal ions cu2+, zn2+, hg2+ and fe3+. the enzy ...	1999	10393084
generation of a novel polysaccharide by inactivation of the acep gene from the acetan biosynthetic pathway in acetobacter xylinum.	the acetan biosynthetic pathway in acetobacter xylinum is an ideal model system for engineering novel bacterial polysaccharides. to genetically manipulate this pathway, an acetobacter strain (cke5), more susceptible to gene-transfer methodologies, was developed. a new gene, acep, involved in acetan biosynthesis was identified, sequenced and shown to have homology at the amino acid level with beta-d-glucosyl transferases from a number of different organisms. disruption of acep in strain cke5 conf ...	1999	10411277
[intramolecular and intermolecular electron transfer reactions in quinoprotein and quinohemoprotein dehydrogenases].		1999	10432834
levansucrase from acetobacter diazotrophicus srt4 is secreted via periplasm by a signal-peptide-dependent pathway.	acetobacter diazotrophicus srt4 secretes a constitutive levansucrase (lsda) (ec 2.4.1.10) that is responsible for sucrose utilization. immunogold electron microscopical studies revealed that lsda accumulates in the periplasm before secretion. the periplasmic and extracellular forms of the enzyme were purified to homogeneity. both proteins exhibited similar physical and biochemical characteristics indicating that lsda adopts its final conformation in the periplasm. the n-terminal sequence of matu ...	1999	10441728
expression and biochemical characterisation of recombinant acea, a bacterial alpha-mannosyltransferase.	biosynthesis of repeat-unit polysaccharides and n-linked glycans proceeds by sequential transfer of sugars from the appropriate sugar donor to an activated lipid carrier. the transfer of each sugar is catalysed by a specific glycosyltransferase. the molecular basis of the specificity of sugar addition is not yet well understood, mainly because of the difficulty of isolating these proteins. in this study, the acea gene product expressed by acetobacter xylinum, which is involved in the biosynthesi ...	1999	10485283
roles of cellulose and xyloglucan in determining the mechanical properties of primary plant cell walls	the primary cell walls of growing and fleshy plant tissue mostly share a common set of molecular components, cellulose, xyloglucan (xyg), and pectin, that are required for both inherent strength and the ability to respond to cell expansion during growth. to probe molecular mechanisms underlying material properties, cell walls and analog composites from acetobacter xylinus have been measured under small deformation and uniaxial extension conditions as a function of molecular composition. small de ...	1999	10517858
identification, sequencing and structural analysis of a nifa-like gene of acetobacter diazotrophicus.	a recombinant plasmid, pad101, containing a dna fragment of acetobacter diazotrophicus strain pal5 was isolated by its ability to restore nif+ phenotype to a nifa- ntrc- double mutant of azotobacter vinelandii. hybridization with the nifa genes of azospirillum brasilense located the nifa gene more precisely to specific fragments of pad101. dna sequencing of appropriate subclones of pad101 revealed that the nifa gene was adjacent to the nifb gene in a. diazotrophicus, and the 5' end of the nifb g ...	1999	10530336
the respiratory system and diazotrophic activity of acetobacter diazotrophicus pal5.	the characteristics of the respiratory system of acetobacter diazotrophicus pal5 were investigated. increasing aeration (from 0.5 to 4.0 liters of air min(-1) liter of medium(-1)) had a strong positive effect on growth and on the diazotrophic activity of cultures. cells obtained from well-aerated and diazotrophically active cultures possessed a highly active, membrane-bound electron transport system with dehydrogenases for nadh, glucose, and acetaldehyde as the main electron donors. ethanol, suc ...	1999	10559164
acid hydrolysis of bacterial cellulose reveals different modes of synergistic action between cellobiohydrolase i and endoglucanase i.	intact and partially acid hydrolyzed cellulose from acetobacter xylinum were used as model substrates for cellulose hydrolysis by 1,4-beta-d-glucan-cellobiohydrolase i (cbh i) and 1,4-beta-d-endoglucanase i (eg i) from trichoderma reesei. a high synergy between cbh i and eg i in simultaneous action was observed with intact bacterial cellulose (bc), but this synergistic effect was rapidly reduced by acid pretreatment of the cellulose. moreover, a distinct synergistic effect was observed upon sequ ...	1999	10561572