| primary structures of alcohol and aldehyde dehydrogenase genes of entamoeba histolytica. | ethanol is the major metabolic product of glucose fermentation by the protozoan parasite e. histolytica under the anaerobic conditions found in the lumen of the colon. with the goal of finding new targets for anti-amebic drugs, the e. histolytica nadp(+)-dependent alcohol dehydrogenase gene (ehadh1; ec 1.1.1.2) and an aldehyde dehydrogenase gene (ehaldh1; ec 1.3.2) were cloned. the ehadh1 alcohol dehydrogenase gene encoded -39 kda protein with 62 and 60% amino acid identities, respectively, with ... | 1992 | 1340318 |
| cloning and expression of an nadp(+)-dependent alcohol dehydrogenase gene of entamoeba histolytica. | ethanol is the major metabolic product of glucose fermentation by the protozoan parasite entamoeba histolytica under the anaerobic conditions found in the lumen of the colon. here an internal peptide sequence determined from a major 39-kda amoeba protein isolated by isoelectric focusing followed by sds/page was used to clone the gene for the e. histolytica nadp(+)-dependent alcohol dehydrogenase (ehadh1; ec 1.1.1.2). the ehadh1 clone had an open reading frame that was 360 amino acids long and en ... | 1992 | 1438208 |
| three-dimensional structure of the surface protein layer (mw layer) of bacillus brevis 47. | the three-dimensional (3d) structure of one surface protein layer from bacillus brevis 47, the middle wall (mw) layer, has been reconstructed from tilted-view electron micrographs after correlation averaging to a resolution of 2 nm. the mw layer has p6 symmetry with a center-to-center spacing of 18.3 nm and a minimum thickness of 5.5 nm. the reconstruction reveals a distinct domain structure: the heavier domain of six monomers jointly forms a massive core centered at the sixfold symmetry axis, a ... | 1989 | 2635709 |
| s-layer protein gene of acetogenium kivui: cloning and expression in escherichia coli and determination of the nucleotide sequence. | acetogenium kivui is anaerobically growing thermophilic bacterium with a gram-positive type of cell wall structure. the outer surface is covered with a hexagonally packed surface (s) layer. the gene coding for the s-layer polypeptide was cloned in escherichia coli on two overlapping fragments by using the plasmid puc18 as the vector. it was expressed under control of a cloned acetogenium promoter or the lacz gene. we determined the complete sequence of the structural gene. the mature polypeptide ... | 1989 | 2681162 |
| enzymatic synthesis of [4r-2h]nad (p)h and [4s-2h]nad(p)h and determination of the stereospecificity of 7 alpha- and 12 alpha hydroxysteroid dehydrogenase. | the stereospecifically labeled coenzymes [4r-2h]nadh, [4r-2h]nadph and [4s-2h]nad(p)h were synthesized enzymatically in high yield and high isotopic purity (greater than or equal to 95%) with 2hcoo2h/formate dehydrogenase, (ch3)2c2hoh/alchol dehydrogenase from thermoanaerobium brockii and [1-2h]glucose/glucose dehydrogenase, respectively. this set of deuterated coenzymes was used to determine the stereospecificity of the previously unstudied 7 alpha-hydroxysteroid dehydrogenase from escherichia ... | 1989 | 2675982 |
| characterization of the h2- and co-dependent chemolithotrophic potentials of the acetogens clostridium thermoaceticum and acetogenium kivui. | strains of clostridium thermoaceticum were tested for h2- and co-dependent growth in a defined medium containing metals, minerals, vitamins, cysteine-sulfide, co2-bicarbonate, and h2 or co. ten of the thirteen strains tested grew at the expense of h2 and co, and c. thermoaceticum atcc 39073 was chosen for further study. the doubling times for h2- and co-dependent growth under chemolithotrophic conditions (the defined medium with nicotinic acid as sole essential vitamin and sulfide as sole reduce ... | 1990 | 2376565 |
| differential effects of sodium on hydrogen- and glucose-dependent growth of the acetogenic bacterium acetogenium kivui. | acetogenium kivui could not be revived or maintained in a sodium-deficient medium (0.2 mm sodium) under h2-dependent conditions, and neither lithium nor potassium replaced the sodium requirement of h2-cultivated cells. conversely, the revival and maintenance of glucose-cultivated cells did not display a dependency on supplemental sodium. in the absence of growth, formate became a major end product in both sodium-deficient and metabolically impaired h2-grown cultures of a. kivui. harmaline, a put ... | 1990 | 2310187 |
| studies of nadp(+)-preferred secondary alcohol dehydrogenase from thermoanaerobium brockii. | alcohol dehydrogenase has been purified from the cell-free preparation of thermoanaerobium brockii to homogeneity, employing combined deae, sephadex, and affinity chromatographic procedures. the enzyme is tetrameric having subunit molecular weight of 40.4 x 10(3). the purified alcohol dehydrogenase is capable of utilizing either nad+ or nadp+ to oxidize primary and secondary alcohols, although it prefers nadp+ as the coenzyme and secondary alcohols as substrates. inactivation of the enzymic acti ... | 1990 | 2204361 |
| purification and characterization of thermostable glucose isomerase from clostridium thermosulfurogenes and thermoanaerobacter strain b6a. | glucose isomerases produced by thermoanaerobacter strain b6a and clostridium thermosulfurogenes strain 4b were purified 10-11-fold to homogeneity and their physicochemical and catalytic properties were determined. both purified enzymes displayed very similar properties (native mr 200,000, tetrameric subunit composition, and apparent ph optima 7.0-7.5). the enzymes were stable at ph 5.5-12.0, and maintained more than 90% activity after incubation at high temperature (85 degrees c) for 1 h in the ... | 1991 | 1996956 |
| purification and properties of f420- and nadp(+)-dependent alcohol dehydrogenases of methanogenium liminatans and methanobacterium palustre, specific for secondary alcohols. | the f420-dependent alcohol dehydrogenase (adh) of methanogenium liminatans and the nadp(+)-dependent adh of methanobacterium palustre were purified to homogeneity. the native f420-dependent adh of mg. liminatans had a molecular mass of 150 kda and consisted of four (presumably identical) subunits with a mass of 39 kda. the temperature optimum was 42 degrees c, the optimum ph 6.0 and nacl or kcl were inhibitory. the nadp(+)-dependent adh of mb. palustre had a molecular mass of 175 kda and consist ... | 1991 | 1879431 |
| characterization of the fructose 1,6-bisphosphate-activated, l(+)-lactate dehydrogenase from thermoanaerobacter ethanolicus. | the l(+)-lactate dehydrogenase from thermoanaerobacter ethanolicus wt was purified to a final specific activity of 598 mumol pyruvate reduced per min per mg of protein. the specific activity of the pure enzyme with l(+)-lactate was 0.79 units per mg of protein. the m(r) of the native enzyme was 134,000 containing a single subunit type of m(r) 33,500 indicating an apparent tetrameric structure. the l(+)-lactate dehydrogenase was activated by fructose 1,6-bisphosphate in a cooperative manner affec ... | 1991 | 1669451 |
| strain selection in carbon-limited chemostats affects reproducibility of thermoanaerobacter ethanolicus fermentations. | we found that the reproducibility of chemostat trials can be improved by using chemostat-adapted strains. our experimental findings are consistent with adaptation that involves an improvement in culture fitness and an alteration of the fermentation genotype. | 1992 | 1610203 |
| alcohol dehydrogenase: multiplicity and relatedness in the solvent-producing clostridia. | alcohol dehydrogenase (adh) is a key enzyme for the production of butanol, ethanol, and isopropanol by the solvent-producing clostridia. initial studies of adh in extracts of several strains of clostridium acetobutylicum and c. beijerinckii gave conflicting molecular properties. a more coherent picture has emerged because of the following results: (i) identification of adhs with different coenzyme specificities in these species; (ii) discovery of structurally conserved adhs (type 3) in three sol ... | 1995 | 7576768 |
| a thermostable nadh oxidase from anaerobic extreme thermophiles. | a high-abundance nadh-oxidizing enzyme (nadh: acceptor oxidoreductase, ec 1.6.99.3) has been identified and isolated from a range of anaerobic extreme thermophiles, including strains of clostridium thermohydrosulfuricum and thermoanaerobium brockii. by use of a pseudo-affinity salt-promoted adsorbent, a nearly pure sample was obtained in one step; remaining impurities were separated by ion-exchange. the fully active purified enzyme contains fad (two molecules per subunit of 75-78 kda) and iron-s ... | 1992 | 1599437 |
| evidence for tyrosine-linked glycosaminoglycan in a bacterial surface protein. | the s-layer protein of acetogenium kivui was subjected to proteolysis with different proteases and several high molecular mass glycosaminoglycan peptides containing glucose, galactosamine and an unidentified sugar-related component were separated by molecular sieve chromatography and reversed-phase hplc and subjected to n-terminal sequence analysis. by methylation analysis glucose was found to be uniformly 1,6-linked, whereas galactosamine was exclusively 1,4-linked. hydrazinolysis and subsequen ... | 1992 | 1596358 |
| purification and characterization of a thermostable beta-xylosidase from thermoanaerobacter ethanolicus. | a highly thermostable beta-xylosidase, exhibiting similarly high activities for arylxylose and arylarabinose, was purified (72-fold) to gel electrophoretic homogeneity from the ethanologenic thermophilic anaerobe thermoanaerobacter ethanolicus. the isoelectric point is ph 4.6; the apparent molecular weight is around 165,000 for the native enzyme (gel filtration and gradient polyacrylamide gel electrophoresis) and 85,000 for the two subunits (sodium dodecyl sulfate-polyacrylamide gel electrophore ... | 1992 | 1522062 |
| thermostable nad(+)-dependent alcohol dehydrogenase from sulfolobus solfataricus: gene and protein sequence determination and relationship to other alcohol dehydrogenases. | the nad(+)-dependent alcohol dehydrogenase (ec 1.1.1.1) from the thermoacidophilic archaebacterium sulfolobus solfataricus, dsm1617 strain (ssadh), has been purified and characterized. its gene has been isolated by screening two s. solfataricus genomic libraries using oligonucleotide probes. the encoding sequence consists of 1041 base pairs, and it shows a high preference for codons ending in t or a. the primary structure, determined by peptide and gene analysis, consists of 347 amino acid resid ... | 1992 | 1463738 |
| molecular cloning and sequence analysis of the gene encoding the h2o2-forming nadh oxidase from streptococcus mutans. | streptococcus mutans induces both h2o2-forming and h2o-forming nadh oxidases in the presence of o2 [m. higuchi, j. gen. microbiol., 130, 1819-1826 (1984)]. in this paper, a nox-1 gene encoding h2o2-forming nadh oxidase (nox-1) from streptococcus mutans was cloned, and the nucleotides sequenced. the structural gene of nox-1 consisted of 1530 base pairs, which encode a polypeptide consisting of 510 amino acids with a predicted molecular mass of 55,196 da. the deduced n-terminal amino acid sequence ... | 1994 | 7765479 |
| immobilization of anaerobic thermophilic bacteria for the production of cell-free thermostable alpha-amylases and pullulanases. | for the production of cell-free thermostable alpha-amylases and pullulanases various anaerobic thermophilic bacteria that belong to the genera clostridium and thermoanaerobacter were immobilized in calcium alginate gel beads. the entrapment of bacteria was performed in full as well as in hollow spheres. an optimal limited medium, which avoided bacterial outgrowth, was developed for the cultivation of immobilized organisms at 60 degrees c using 0.4% starch as substrate. compared to non-immobilize ... | 1990 | 1370007 |
| characterization of the bacillus anthracis s-layer: cloning and sequencing of the structural gene. | bacillus anthracis, a gram-positive, spore-forming bacterium, is the etiological agent of anthrax. the gene coding for the s-layer protein (sap) was cloned on two contiguous fragments in escherichia coli, and the complete sequence of the structural gene was determined. the protein, sap, is composed of 814 residues, including a classical prokaryotic 29-amino-acid signal peptide. the mature form has a calculated molecular mass of 83.7 kda and a molecular mass of 94 kda on a sodium dodecyl sulfate- ... | 1995 | 7836294 |
| coenzymatic properties of low molecular-weight and macromolecular n6-derivatives of nad+ and nadp+ with dehydrogenases of interest for organic synthesis. | the catalytic activity, expressed as km and vmax values, of 16 enzymes of practical interest with the macromolecular coenzymes poly(ethylene glycol)-n6-(2-aminoethyl)-nad+ and poly(ethylene glycol)-n6-(2-aminoethyl)-nadp+ and their low molecular weight precursors n6-(2-aminoethyl)-nad+ and n6-(2-aminoethyl)-nadp+, was investigated. the enzymes examined are of direct interest for organic synthesis (i.e. alcohol dehydrogenase from yeast, horse liver, or thermoanaerobium brockii, lactic dehydrogena ... | 1990 | 1366782 |
| characterization of an alcohol, dehydrogenase from thermoanaerobacter ethanolicus active with ethanol and secondary alcohols. | | 1981 | 7023472 |
| glucose fermentation pathway of thermoanaerobium brockii. | thermoanaerobium brockii was shown to catabolize glucose via the embden-meyerhof-parnas pathway into ethanol, acetic acid, h(2)-co(2), and lactic acid. radioactive tracer studies, employing specifically labeled [(14)c]glucose, demonstrated significant fermentation of (14)co(2) from c-3 and c-4 of the substrate exclusively. all extracts contained sufficient levels of activity (expressed in micromoles per minute per milligram of protein at 40 degrees c) to assign a catabolic role for the following ... | 1980 | 6767705 |
| thermophilic anaerobic bacteria which ferment hemicellulose: characterization of organisms and identification of plasmids. | seven thermophilic anaerobic bacteria which ferment xylan were isolated from natural geothermal features in the western united states. typically, these strains were gram-negative non-sporeforming rods with an unusual double-layered cell wall which resembled that observed in thermobacteroides acetoethylicus. the strains differed from known thermophilic anaerobes in their ability to utilize a very wide variety of carbohydrates and in their ability to grow in a chemically-defined medium and/or at p ... | 1984 | 6742954 |
| thermoanaerobacter ethanolicus in a comparison of the growth efficiencies of thermophilic and mesophilic anaerobes. | maintenance coefficients and theoretical maximum growth yields, with respect to both substrate and atp, were estimated for thermoanaerobacter ethanolicus growing in a glucose-limited, continuous culture. a comparison of these values with those for other bacteria showed that, contrary to predictions by others, anaerobic thermophiles had neither low observed growth yields nor high maintenance energy coefficients. | 1985 | 4030696 |
| active-site- and substrate-specificity of thermoanaerobium tok6-b1 pullulanase. | thermoanaerobium tok6-b1 pullulanase (ec 3.2.1.41) was active on alpha 1-6-glucosidic linkages of pullulan, amylopectin and glycogen and the alpha 1-4 linkages of amylose, amylopectin and glycogen but not of pullulan. hydrolysis of short-chain-length malto-oligosaccharides (seven or fewer glucose residues) yielded maltose as product. pullulan hydrolysis was ph-dependent and a plot of log(v/km) versus ph implied a carboxy group with pka 4.3 at the active site. modification with 1-(3-dimethylamino ... | 1987 | 3500710 |
| domain structure of the acetogenium kivui surface layer revealed by electron crystallography and sequence analysis. | the three-dimensional structure of the acetogenium kivui surface layer (s-layer) has been determined to a resolution of 1.7 nm by electron crystallographic techniques. two independent reconstructions were made from layers negatively stained with uranyl acetate and na-phosphotungstate. the s-layer has p6 symmetry with a center-to-center spacing of approximately 19 nm. within the layer, six monomers combine to form a ring-shaped core surrounded by a fenestrated rim and six spokes that point toward ... | 1994 | 8113161 |
| synthesis of 4r- and 4s-tritium labeled nadph for the determination of the coenzyme stereospecificity of nadph: protochlorophyllide oxidoreductase. | a rapid and easy method for the production of both the 4r and 4s tritium labeled isomers of either nadh or nadph has been developed. the method requires the use of only a single labeled compound (d-[1(-3)h] glucose), and two enzymes (glucose dehydrogenase from bacillus sp. and alcohol dehydrogenase from thermoanaerobium brockii) which are specific for the pro s and pro r hydrogens, respectively, of either nadh or nadph. the 4r and 4s tritium labeled isomers of nadph have been used to determine t ... | 1987 | 3314870 |
| a cell-associated oligo-1,6-alpha-glucosidase from an extremely thermophilic anaerobic bacterium, thermoanaerobium tok6-b1. | cell-associated oligo-1,6-alpha-glucosidase (ec 3.2.1.10) was isolated from thermoanaerobium tok6-b1 grown on starch-containing medium. activity was purified 11.4-fold by salt precipitation, gel filtration, hydroxyapatite and anion-exchange chromatography. molecular mass was determined as 30,000 by sds/polyacrylamide-gel electrophoresis and 33,000 by analytical gel filtration. the probable order of specificity was p-nitrophenyl-alpha d-glucose greater than-isomaltose greater than-isomaltotriose ... | 1988 | 3214428 |
| cloning of the debranching-enzyme gene from thermoanaerobium brockii into escherichia coli and bacillus subtilis. | the gene for an enzyme with single or dual specificity on complex carbohydrates has been transferred from its native host (thermoanaerobium brockii), a thermophilic anaerobe, into escherichia coli and bacillus subtilis. most of the gene coding region is in a 2.2-kilobase psti fragment that is common to the e. coli and b. subtilis chimeric vectors pcpc902 and pcpc903, respectively. although the t. brockii debranching enzyme secreted from b. subtilis was unglycosylated and had less thermostability ... | 1987 | 3040687 |
| determination of intracellular pyridine nucleotide levels by bioluminescence using anaerobic bacteria as a model. | an assay for the determination of nad(p)+ and nad(p)h in extracts from the obligate anaerobe bacterium thermoanaerobacter finnii is developed and the strategy for this development is described. this assay performed with constant fmn reductase (ec 1.6.8.1) and luciferase (ec 1.14.14.3) concentrations has been shown to detect as low as 1 pmol pyridine nucleotide. with this assay recovery, efficiency of extraction, reliability, and detection limit of the procedures were determined. to our knowledge ... | 1989 | 2817339 |
| amino acid sequence of alcohol dehydrogenase from the thermophilic bacterium thermoanaerobium brockii. | the complete amino acid sequence of alcohol dehydrogenase of thermoanaerobium brockii (tbad) is presented. the s-carboxymethylated protein was cleaved at methionine residues (with cyanogen bromide) to provide a set of 10 nonoverlapping fragments accounting for 90% of the sequence. these fragments were then overlapped and aligned, and the sequence was completed by using peptides generated by proteolytic cleavage at lysine residues (with achromobacter protease i). the protein subunit contained 352 ... | 1989 | 2790012 |
| nickel transport by the thermophilic acetogen acetogenium kivui. | exogenous 63ni was incorporated into carbon monoxide dehydrogenase when acetogenium kivui atcc 33488 was cultivated in the presence of 63nicl2. the capacity for nickel (63nicl2) transport was greatest with cells harvested from the mid- to late exponential phases of growth. nickel transport was linear during the transport assay period and displayed saturation kinetics. the apparent km and vmax for nickel transport by h2-cultivated cells approximated 2.3 microm ni and 670 pmol of ni transported pe ... | 1989 | 2757374 |
| novel nadp-linked alcohol--aldehyde/ketone oxidoreductase in thermophilic ethanologenic bacteria. | an nadp-specific alcohol--aldehyde/ketone oxidoreductase was detected in cell extracts of thermoanaerobium brockii and clostridium thermohydrosulfuricum, but not in thermobacteroides acetoethylicus or clostridium thermocellum. the enzyme was purified from ta. brockii by differential procedures that included heat treatment and an affinity-chromatography step on blue dextran--sepharose. the 44-fold-purified enzyme displayed one band (mol.wt. approx. 40000) after sodium dodecyl sulphate/polyacrylam ... | 1981 | 7030321 |
| ethanol production by thermophilic bacteria: metabolic control of end product formation in thermoanaerobium brockii. | specific changes in the chemical and microbial composition of thermoanaerobium brockii fermentations were compared and related to alterations of process rates, end product yields, and growth parameters. fermentation of starch as compared with glucose was associated with significant decreases in growth rate and intracellular fructose-1,6-bisphosphate concentration and with a dramatic increase in the ethanol/lactate product ratio. glucose or pyruvate fermentation in the presence of acetone was cor ... | 1981 | 7217000 |
| some aspects of thermophilic and extreme thermophilic anaerobic microorganisms. | in this presentation, we have discussed that the acetogenic thermophilic bacterium, clostridium thermoaceticum, ferments glucose almost quantitatively to acetate. that part of the acetate is formed from co2, which functions as the electron sink. we have demonstrated that enzymes in the acetate formation contain trace elements such as iron, cobalt, nickel, selenium and tungsten. furthermore, we have indicated that this bacterium must have an electron transport system, which is not yet completely ... | 1981 | 7271714 |
| organization of a clostridium thermocellum gene cluster encoding the cellulosomal scaffolding protein cipa and a protein possibly involved in attachment of the cellulosome to the cell surface. | the nucleotide sequence was determined for a 9.4-kb region of clostridium thermocellum dna extending from the 3' end of the gene (now termed cipa), encoding the s1/sl component of the cellulosome. three open reading frames (orfs) belonging to two operons were detected. they encoded polypeptides of 1,664, 688, and 447 residues, termed orf1p, orf2p, and orf3p, respectively. the cooh-terminal regions of the three polypeptides were highly similar and contained three reiterated segments of 60 to 70 r ... | 1993 | 8458832 |
| microbiology of methanogenesis in thermal, volcanic environments. | microbial methanogenesis was examined in thermal waters, muds, and decomposing algal-bacterial mats associated with volcanic activity in yellowstone national park. radioactive tracer studies with [(14)c]glucose, acetate, or carbonate and enrichment culture techniques demonstrated that methanogenesis occurred at temperatures near 70 degrees c but below 80 degrees c and correlated with hydrogen production from either geothermal processes or microbial fermentation. three methanobacterium thermoauto ... | 1980 | 7400098 |
| ethanol production by thermophilic bacteria: relationship between fermentation product yields of and catabolic enzyme activities in clostridium thermocellum and thermoanaerobium brockii. | significant quantitative differences in end-product yields by two strains of clostridium thermocellum and one strain of thermoanaerobium brockii were observed during cellobiose fermentation. most notably, the ethanol/h(2) and lactate/acetate ratios were drastically higher for t. brockii as compared with c. thermocellum strains lqri and as39. exogenous h(2) addition (0.4 to 1.0 atm) during culture growth increased the ethanol/acetate ratio of both t. brockii and as39 but had no effect on lqri. al ... | 1980 | 7430065 |
| new reactive coenzyme analogues for affinity labeling of nad+ and nadp+ dependent dehydrogenases. | reactive coenzyme analogues omega-(3-diazoniumpyridinium)alkyl adenosine diphosphate were prepared by reaction of omega-(3-aminopyridinium)alkyl adenosine diphosphate with nitrous acid. in these compounds the nicotinamide ribose is substituted by hydrocarbon chains of varied lengths (n-ethyl to n-pentyl). the diazonium compounds are very unstable and decompose rapidly at room temperature. they show a better stability to 0 degree c. lactate and alcohol dehydrogenase do not react with any of the a ... | 1995 | 7546038 |
| description of thermoanaerobacter brockii subsp. lactiethylicus subsp. nov., isolated from a deep subsurface french oil well, a proposal to reclassify thermoanaerobacter finnii as thermoanaerobacter brockii subsp. finnii comb. nov., and an emended description of thermoanaerobacter brockii. | a strictly anaerobic, thermophilic, gram-positive, spore-forming cubacterium designated strain serb 5268t (t = type strain) was isolated from an oil field at a depth of 2,100 m, where the temperature was 92 degrees c. the cells of this organism were gram-positive, straight, motile rods (0.5 by 2 to 3 microns) with peritrichous flagella. the cells occurred singly or in pairs during the logarithmic growth phase, but were pleomporphic and filamentous (length, 15 microns) in old cultures. growth occ ... | 1995 | 7547300 |
| the single-ring thermoanaerobacter brockii chaperonin 60 (tbr-el7) dimerizes to tbr-el14.tbr-es7 under protein folding conditions. | chaperone proteins assist in the folding of some newly synthesized proteins and inhibit protein aggregation. the thermoanaerobacter brockii chaperonin proteins (tbr-el and tbr-es) have recently been purified and characterized [truscott, w.n., høj, p. b., & scopes, r. k. (1994) eur. j. biochem. 222, 277-284]; tbr-el was a single seven-membered toroid, unlike most groels which exist as double toroids. using high-resolution gel filtration chromatography, we have resolved the purified tbr-el into si ... | 1995 | 7578105 |
| nucleotide sequence and chromosomal localization of the gene encoding the old yellow enzyme from kluyveromyces lactis. | a 6.6 kb genomic dna fragment from the yeast kluyveromyces lactis was isolated. sequence analysis of this fragment revealed the presence of two incomplete open reading frames (orfs) in one strand, one coding for the carboxyl terminus of the plasma membrane h(+)-atpase and the other for the amino terminus of an unidentified product. in the complementary strand, a full-length orf which encodes for a protein homologous to the yeast nadph-dependent old yellow enzyme was found. the deduced amino acid ... | 1995 | 7597850 |
| phylogenetic analysis of anaerobic thermophilic bacteria: aid for their reclassification. | small subunit rdna sequences were determined for 20 species of the genera acetogenium, clostridium, thermoanaerobacter, thermoanaerobacterium, thermoanaerobium, and thermobacteroides, 3 non-validly described species, and 5 isolates of anaerobic thermophilic bacteria, providing a basis for a phylogenetic analysis of these organisms. several species contain a version of the molecule significantly longer than that of escherichia coli because of the presence of inserts. on the basis of normal evolut ... | 1993 | 7687600 |
| similarity of "core" structures in two different glycans of tyrosine-linked eubacterial s-layer glycoproteins. | previously, the repeating-unit structure of the s-layer glycoprotein from the eubacterium bacillus alvei ccm 2051 has been determined to be [-->3)-beta-d-galp-(1-->4)-[alpha-d-glcp-(1-->6)-]-beta-d-manpnac- (1-->]n (e. altman, j.-r. brisson, p. messner, and u. b. sleytr, biochem. cell biol. 69:72-78, 1991). nuclear magnetic resonance spectroscopic reexamination of this glycan reveals that the o-antigen-like domain of the polysaccharide is [see text] connected with the s-layer polypeptide through ... | 1995 | 7721708 |
| the phylogeny of the genus clostridium: proposal of five new genera and eleven new species combinations. | the 16s rrna gene sequences of 34 named and unnamed clostridial strains were determined by pcr direct sequencing and were compared with more than 80 previously determined clostridial sequences and the previously published sequences of representative species of other low- g + c-content gram-positive genera, thereby providing an almost complete picture of the genealogical interrelationships of the clostridia. the results of our phylogenetic analysis corroborate and extend previous findings in show ... | 1994 | 7981107 |
| purification of acetaldehyde dehydrogenase and alcohol dehydrogenases from thermoanaerobacter ethanolicus 39e and characterization of the secondary-alcohol dehydrogenase (2 degrees adh) as a bifunctional alcohol dehydrogenase--acetyl-coa reductive thioesterase. | the purification and characterization of three enzymes involved in ethanol formation from acetyl-coa in thermoanaerobacter ethanolicus 39e (formerly clostridium thermohydrosulfuricum 39e) is described. the secondary-alcohol dehydrogenase (2 degrees adh) was determined to be a homotetramer of 40 kda subunits (sds/page) with a molecular mass of 160 kda. the 2 degrees adh had a lower catalytic efficiency for the oxidation of 1 degree alcohols, including ethanol, than for the oxidation of secondary ... | 1994 | 8068002 |
| a new family of very long chain alpha,omega-dicarboxylic acids is a major structural fatty acyl component of the membrane lipids of thermoanaerobacter ethanolicus 39e. | a new family of alpha,omega-dicarboxylic, very long chain fatty acids was isolated and characterized from the lipids of thermophilic anaerobic eubacterium, thermoanaerobacter ethanolicus 39e. after the isolation of the membrane, the fatty acyl components were converted to methyl esters by acid-catalyzed methanolysis. the esterified fatty acyl components were purified by a variety of chromatographic techniques and analyzed by gas chromatography (gc) and gc-mass spectrometry (ms). one of the isola ... | 1994 | 8077844 |
| stereospecificity of hydrogen transfer by the nadp-linked alcohol dehydrogenase from the thermophilic bacterium thermoanaerobium brockii. | class a and class b nad(h)/nadp(h) coenzyme-dependent dehydrogenases distinguish between the diastereotopic hydrogens pro-r and pro-s at position 4 of the cofactor. we investigated the stereochemistry of hydride transfer in reactions catalyzed by an unusual thermophilic, zinc-containing, nadp-linked enzyme thermoanaerobium brockii alcohol dehydrogenase (tbad). using proton nmr spectroscopy of monodeuterated alcohols and coenzymes we found that tbad is a class a enzyme that transfers the pro-r hy ... | 1993 | 8106201 |
| primary structure of the o-glycosidically linked glycan chain of the crystalline surface layer glycoprotein of thermoanaerobacter thermohydrosulfuricus l111-69. galactosyl tyrosine as a novel linkage unit. | the products of pronase digestion of the crystalline surface layer (s-layer) glycoproteins of thermoanaerobacter thermohydrosulfuricus strains l111-69 and l110-69 were isolated by gel permeation chromatography, cation exchange chromatography, chromatofocusing, and reversed phase high performance liquid chromatography. four compounds were obtained which were analyzed by monosaccharide analysis, one- and two-dimensional 500 and 600 mhz 1h and 13c nmr spectroscopy, methylation analysis, gas-liquid ... | 1994 | 8125923 |
| pullulanase of thermoanaerobacterium thermosulfurigenes em1 (clostridium thermosulfurogenes): molecular analysis of the gene, composite structure of the enzyme, and a common model for its attachment to the cell surface. | the complete pullulanase gene (amyb) from thermoanaerobacterium thermosulfurigenes em1 was cloned in escherichia coli, and the nucleotide sequence was determined. the reading frame of amyb consisted of 5,586 bp encoding an exceptionally large enzyme of 205,991 da. sequence analysis revealed a composite structure of the pullulanase consisting of catalytic and noncatalytic domains. the n-terminal half of the protein contained a leader peptide of 35 amino acid residues and the catalytic domain, whi ... | 1994 | 8195085 |
| sequencing of the amylopullulanase (apu) gene of thermoanaerobacter ethanolicus 39e, and identification of the active site by site-directed mutagenesis. | the complete nucleotide sequence of the gene encoding the dual active amylopullulanase of thermoanaerobacter ethanolicus 39e (formerly clostridium thermohydrosulfuricum) was determined. the structural gene (apu) contained a single open reading frame 4443 base pairs in length, corresponding to 1481 amino acids, with an estimated molecular weight of 162,780. analysis of the deduced sequence of apu with sequences of alpha-amylases and alpha-1,6 debranching enzymes enabled the identification of four ... | 1993 | 8344920 |
| purification and characterization of a primary-secondary alcohol dehydrogenase from two strains of clostridium beijerinckii. | two primary alcohols (1-butanol and ethanol) are major fermentation products of several clostridial species. in addition to these two alcohols, the secondary alcohol 2-propanol is produced to a concentration of about 100 mm by some strains of clostridium beijerinckii. an alcohol dehydrogenase (adh) has been purified to homogeneity from two strains (nrrl b593 and neste 255) of 2-propanol-producing c. beijerinckii. when exposed to air, the purified adh was stable, whereas the partially purified ad ... | 1993 | 8349550 |
| cloning, sequencing and expression of the gene encoding nadh oxidase from the extreme anaerobic thermophile thermoanaerobium brockii. | the gene encoding the enzyme nadh oxidase from the extreme thermophile thermoanaerobium brockii has been isolated from a recombinant library of genomic dna and sequenced. an open reading frame corresponds to the 651 amino acids of the enzyme's subunit, which include characteristic fad- and nadh-binding sequences, as well as cysteines which are involved in the fes cluster present in the enzyme. the enzyme is expressed either from its own promoter or from vector promoters in escherichia coli. afte ... | 1993 | 8357835 |
| cloning, sequencing and biochemical characterization of xylose isomerase from thermoanaerobacterium saccharolyticum strain b6a-ri. | the xylose isomerase gene from thermoanaerobacterium saccharolyticum strain b6a-ri was cloned by complementation using escherichia coli xyl-5 mutant strain hb101. one positive clone was detected and the recombinant plasmid, pzx16, was isolated. the clone contained the vector puc18 and an insert fragment of 4.5 kb. the cloned xylose isomerase gene (xyla) was expressed constitutively in e. coli. the gene contained one open reading frame (orf) of 1317 bp, which corresponds to 439 amino acid residue ... | 1993 | 8360616 |
| analysis of the catalytic center of cyclomaltodextrinase from thermoanaerobacter ethanolicus 39e. | the amino acid sequences of cyclomaltodextrinase (cdase) from thermoanaerobacter ethanolicus 39e (formerly clostridium thermohydrosulfuricum 39e) and other amylolytic enzymes were compared by using linear alignment and hydrophobic cluster analysis. two asp and one glu residue, which were considered to be the catalytic residues of the compared enzymes according to crystallographic or protein engineering experiments, were also conserved in cdase. asp325, asp421 and glu354 of the cdase were individ ... | 1993 | 8425614 |
| crystal parameters of an alcohol dehydrogenase from the extreme thermophile thermoanaerobium brockii. | a bacterial thermophilic alcohol dehydrogenase which is stable and active at 85 degrees c, has been crystallized by vapor diffusion from solutions of polyethylene glycol. a monoclinic crystal form diffracts to 2.8 a resolution and belongs to space group c2 with unit cell dimensions a = 139.0 a, b = 137.4 a, c = 80.9 a and beta = 93.23 degrees. the asymmetric unit contains four molecules which exhibit 222 point symmetry. a second crystal form is orthohombic, space group p2(1)2(1)2 with unit cell ... | 1993 | 8450548 |
| old yellow enzyme. the discovery of multiple isozymes and a family of related proteins. | using fast protein liquid chromatography, we have separated native old yellow enzyme from brewer's bottom yeast into three distinct fractions. two of these fractions are homodimeric forms of the enzyme while the third is the corresponding heterodimeric form. one of these homodimeric fractions is identical in every respect to oye1, originally cloned from brewer's bottom yeast (saito, k., thiele, d. j., davio, m., lockridge, o., and massey, v. (1991) j. biol. chem. 266, 20720-20724). we have clone ... | 1993 | 8454584 |
| characterization of the baih gene encoding a bile acid-inducible nadh:flavin oxidoreductase from eubacterium sp. strain vpi 12708. | a cholate-inducible, nadh-dependent flavin oxidoreductase from the intestinal bacterium eubacterium sp. strain vpi 12708 was purified 372-fold to apparent electrophoretic homogeneity. the subunit and native molecular weights were estimated to be 72,000 and 210,000, respectively, suggesting a homotrimeric organization. three peaks of nadh:flavin oxidoreductase activity (forms i, ii, and iii) eluted from a deae-high-performance liquid chromatography column. absorption spectra revealed that purifie ... | 1993 | 8491719 |
| characterization of a new obligately anaerobic thermophile, thermoanaerobacter wiegelii sp. nov. | an obligately anaerobic, extremely thermophilic thermoanaerobacter species was isolated from a freshwater pool formed from a geothermally heated (56 to 69 degrees c) water outlet in government gardens, rotorua, new zealand. this organism was a spore-forming, gram-negative, rod-shaped bacterium. strain rt8.b1t (= dsm 10319t) (t = type strain) fermented a wide variety of mono-, di-, and polysaccharides and produced ethanol, acetate, lactate, propionate, and hydrogen. sugar alcohols were also ferme ... | 1996 | 8573487 |
| a t7 promoter-specific, inducible protein expression system for bacillus subtilis. | the adaptation and application of the escherichia coli t7 rna polymerase system for regulated and promoter-specific gene expression in bacillus subtilis is reported. the expression cassette used in bacillus subtilis was tightly regulated and t7 rna polymerase (t7 rnap)appeared 30 minutes after induction. the efficiency of t7 promoter-specific gene expression in b.subtilis was studied using one secretory and two cytosolic proteins of heterologous origin. the accumulation of e. coli beta-galactosi ... | 1996 | 8628223 |
| hydrostatic pressure induces conformational and catalytic changes on two alcohol dehydrogenases but no oligomeric dissociation. | a comparison between the pressure effects on the catalysis of thermoanaerobium brockii alcohol dehydrogenase (tbadh: a thermostable tetrameric enzyme) and yeast alcohol dehydrogenase (yadh: a mesostable tetrameric enzyme) revealed a different behaviour. yadh activity is continuously inhibited by an increase of pressure, whereas yadh affinity seems less sensitive to pressure. tbadh activity is enhanced by pressure up to 100 mpa. tbadh affinity for alcoholic substrates increases if pressure increa ... | 1996 | 8639709 |
| cloning and expression of the gene encoding the thermoanaerobacter ethanolicus 39e secondary-alcohol dehydrogenase and biochemical characterization of the enzyme. | the adhb gene encoding thermoanaerobacter ethanolicus 39e secondary-alcohol dehydrogenase (s-adh) was cloned, sequenced and expressed in escherichia coli. the 1056 bp gene encodes a homotetrameric recombinant enzyme consisting of 37.7 kda subunits. the purified recombinant enzyme is optimally active above 90 degrees c with a half-life of approx. 1.7 h at 90 degrees c. an nadp(h)-dependent enzyme, the recombinant s-adh has 1400-fold greater catalytic efficiency in propan-2-ol oxidation than in et ... | 1996 | 8645192 |
| effect of thiosulphate as electron acceptor on glucose and xylose oxidation by thermoanaerobacter finnii and a thermoanaerobacter sp. isolated from oil field water. | during glucose and xylose fermentation, thermoanaerobacter finnii was observed to produce lactate, acetate, h2 and co2, with ethanol being the major end product. thermoanaerobacter strain sebr 5268, an isolate from an oil field, also produced a similar range of end products from glucose and xylose fermentation, with the exception that both ethanol and lactate were the major products of sugar metabolism. both these strains were able to reduce thiosulphate to sulphide in the presence of these two ... | 1996 | 8761734 |
| a novel thermostable dextranase from a thermoanaerobacter species cultured from the geothermal waters of the great artesian basin of australia. | a gram-negative sporulating thermophilic anaerobe, designated ab11ad, was isolated from the heated waters of the great artesian basin of australia. it grew on a variety of carbohydrates including glucose, starch, and dextran and produced a thermostable and thermoactive extracellular endo-dextranase. the enzyme was produced more actively under ph controlled continuous culture conditions than under batch conditions. ammonium sulfate precipitated crude dextranase exhibited a temperature optimum of ... | 1996 | 8764490 |
| two-dimensional paracrystalline glycoprotein s-layers as a novel matrix for the immobilization of human igg and their use as microparticles in immunoassays. | in the present study, cup-shaped 1-3 microns large cell wall fragments from thermoanaerobacter thermohydrosulfuricus l111-69 covered with a hexagonal s-layer lattice composed of glycoprotein subunits were shown to act as a matrix for the immobilization of human igg. after cross-linking the s-layer glycoprotein lattice with glutaraldehyde (s-layer microparticles), igg was either bound to carbodiimide activated carboxyl groups from acidic amino acids from the protein moiety or to the carbohydrate ... | 1996 | 8841445 |
| a method of preparation and purification of (4r)-deuterated-reduced nicotinamide adenine dinucleotide phosphate. | (4r)-deuterated-reduced nicotinamide adenine dinucleotide phosphate, (4r)-[2h]nadph, was prepared by reduction of nadp+ using an nadp(+)-dependent alcohol dehydrogenase (ec 1.1.1.2) from thermoanaerobium brockii and isopropanol-d8 as substrate at 43 degrees c, ph 9. more than 80% of the product was identified as reduced cofactor by reverse-phase (ods) hplc, and a 1h nmr study showed that all of the reduced cofactor was (4r)-deuterated. less than 10% of the product was oxidized cofactor, the rema ... | 1994 | 7810866 |
| amino acid substitutions in the yeast pichia stipitis xylitol dehydrogenase coenzyme-binding domain affect the coenzyme specificity. | directed mutagenesis has been used to identify a set of amino acids in the pichia stipitis xylitol dehydrogenase, encoded by the xylitol dehydrogenase gene xyl2, which is involved in specific nad binding. within the binding domain, a characteristic beta alpha beta-fold is centered around a glycine motif gxgxxg also containing conserved aspartate and lysine/arginine residues. the mutation d207-->g and the double mutation d207-->g and d210-->g increased the apparent km for nad ninefold and decreas ... | 1995 | 7883010 |
| purification and characterization of chaperonin 60 and chaperonin 10 from the anaerobic thermophile thermoanaerobacter brockii. | chaperonin 60 and chaperonin 10 (groel and groes homologues, respectively) have been isolated from extracts of the anaerobic thermophile thermoanaerobacter brockii. a simple and rapid purification for chaperonin 60 made use of hydrophobic and anion-exchange chromatographies, and could be readily scaled up; approximately 2 mg pure chaperonin 60 was obtained/g cells. in contrast with all other prokaryotic chaperonin 60 proteins that have been studied, which are tetradecamers, including those from ... | 1994 | 7912671 |
| thermoanaerobacter brockii alcohol dehydrogenase: characterization of the active site metal and its ligand amino acids. | the active-site metal ion and the associated ligand amino acids in the nadp-linked, tetrameric enzyme thermoanaerobacter brockii alcohol dehydrogenase (tbadh) were characterized by atomic absorption spectroscopy analysis and site-directed mutagenesis. our preliminary results indicating the presence of a catalytic zinc and the absence of a structural metal ion in tbadh (peretz & burstein. 1989. biochemistry 28:6549-6555) were verified. to determine the role of the putative active-site zinc, we in ... | 1997 | 9041649 |
| new alcohol dehydrogenases for the synthesis of chiral compounds. | the enantioselective reduction of carbonyl groups is of interest for the production of various chiral compounds such as hydroxy acids, amino acids, hydroxy esters, or alcohols. such products have high economic value and are most interesting as additives for food and feed or as building blocks for organic synthesis. enzymatic reactions or biotransformations with whole cells (growing or resting) for this purpose are described. although conversions with whole cells are advantageous with respect to ... | 1997 | 9103913 |
| cysteine reactivity in thermoanaerobacter brockii alcohol dehydrogenase. | the free cysteine residues in the extremely thermophilic thermoanaerobacter brockii alcohol dehydrogenase (tbadh) were characterized using selective chemical modification with the stable nitroxyl biradical bis(1-oxy-2,2,5,5-tetramethyl-3-imidazoline-4-yl)disulfide, via a thiol-disulfide exchange reaction and with 2[14c]iodoacetic acid, via s-alkylation. the respective reactions were monitored by electron paramagenetic resonance (epr) and by the incorporation of the radioactive label. in native t ... | 1997 | 9144779 |
| clostridium thermocellum jw20 (atcc 31549) is a coculture with thermoanaerobacter ethanolicus. | a pcr assay based on 16s rrna sequence differences among four thermophilic anaerobic bacterial strains was used to demonstrate contamination of clostridium thermocellum jw20 (atcc 31549) with a thermoanaerobacter ethanolicus strain. therefore, we suggest that interpretation of experimental results with c. thermocellum jw20 be viewed with caution. | 1997 | 9212442 |
| [cloning and expression of the gene for thermostable beta-galactosidase from thermoanaerobacter ethanolicus in escherichia coli: purification and properties of the product]. | an anaerobic thermophilic bacterium thermoanaerobacter ethanolicus 39e (clostridium thermohydrosulfuricum 39e) gene library was constructed in e. coli. recombinant plasmid (put50) containing the thermostable beta-galactosidase was isolated by direct selection of clones for enzyme activity using 5-bromo-4-chloro-3-indolyl-d-galactopyranoside (x-gal) and mapping procedures were carried out. the beta-galactosidase was purified from cell extracts of e. coli. physicochemical characteristics of the re ... | 1997 | 9213771 |
| dissimilatory reduction of fe(iii) by thermophilic bacteria and archaea in deep subsurface petroleum reservoirs of western siberia | twenty-five samples of stratal fluids obtained from a high-temperature (60-84 degrees c) deep subsurface (1700-2500 m) petroleum reservoir of western siberia were investigated for the presence of dissimilatory fe(iii)-reducing microorganisms. of the samples, 44% and 76% were positive for fe(iii) reduction with peptone and h2 respectively as electron donors. in most of these samples, the numbers of culturable thermophilic h2-utilizing iron reducers were in the order of 10-100 cells/ml. nine strai ... | 1999 | 10398835 |
| dethiosulfovibrio peptidovorans gen. nov., sp. nov., a new anaerobic, slightly halophilic, thiosulfate-reducing bacterium from corroding offshore oil wells. | a strictly anaerobic thiosulfate-reducing bacterium was isolated from a corroding offshore oil well in congo and was designated strain sebr 4207t. pure culture of the strain induced a very active pitting corrosion of mild steel, with penetration rates of up to 4 mm per year. this constitutes the first experimental evidence of the involvement of thiosulfate reduction in microbial corrosion of steel. strain sebr 4207t cells were vibrios (3 to 5 by 1 microns), stained gram negative, and possessed l ... | 1997 | 9226912 |
| thermoanaerobacter mathranii sp. nov., an ethanol-producing, extremely thermophilic anaerobic bacterium from a hot spring in iceland. | the extremely thermophilic ethanol-producing strain a3 was isolated from a hot spring in iceland. the cells were rod-shaped, motile, and had terminal spores; cells from the mid-to-late exponential growth phase stained gram-variable but had a gram-positive cell wall structure when viewed by transmission electron microscopy. strain a3 used a number of carbohydrates as carbon sources, including xylan, but did not utilize microcrystalline cellulose. fermentation end products were ethanol, acetate, l ... | 1997 | 9238102 |
| the enantiomeric purity of alcohols formed by enzymatic reduction of ketones can be improved by optimisation of the temperature and by using a high co-substrate concentration. | the stereoselective reduction of ketones by alcohol dehydrogenase from thermoanaerobium brockii was studied in organic reaction media. 2-propanol was used as co-substrate to regenerate the coenzyme nadph. the enantiomeric excess of the alcohol formed from the ketone decreased during the course of the reaction (from 53 to 0% e.e. in the formation of (r)-2-butanol). this was interpreted as being due to the reversibility of all the reactions involved. by using a large excess of 2-propanol this effe ... | 1997 | 9271250 |
| chemoenzymatic synthesis of chiral biologically active heterocycles. | the chemoenzymatic approach to the preparation of some chiral biologically active heterocycles is discussed. synthetic strategies took advantage of enantioselective bioconversion processes carried out on suitable reaction intermediates. reductions of carbonyl compounds catalyzed by different alcohol dehydogenases (tbadh from thermoanaerobium brockii, 20 beta-hsdh from streptomyces hydrogenans, beta-hsdh from pseudomonas testosteroni) allowed the preparation with high enantiomeric purity of the e ... | 1997 | 9274001 |
| genes encoding two different beta-glucosidases of thermoanaerobacter brockii are clustered in a common operon. | a 5.9-kb fragment of chromosomal dna coding for beta-glucosidase activity of the thermophilic anaerobe thermoanaerobacter brockii was sequenced. two genes, cglt and xgls, encoding a cellodextrin-cleaving beta-glucosidase and a xylodextrin-degrading xylo-beta-glucosidase, respectively, were located directly adjacent to each other. the 5' region contained two additional genes, cglf and cglg, whose products exhibited similarity to integral membrane proteins of metabolite transport systems. the two ... | 1997 | 9327554 |
| carbonic anhydrase in acetobacterium woodii and other acetogenic bacteria. | acetobacterium woodii, acetohalobium arabaticum, clostridium formicoaceticum, and sporomusa silvacetica were found to contain carbonic anhydrase (ca). minimal to no ca activity was detected in moorella thermoautotrophica, moorella thermoacetica subsp. "pratumsolum," sporomusa termitida, and thermoanaerobacter kivui. of the acetogens tested, a. woodii had the highest ca specific activity, approximately 14 u mg of protein(-1), in extracts of either glucose- or h2-co2-cultivated cells. ca of a. woo ... | 1997 | 9371472 |
| a novel type of thermostable alpha-d-glucosidase from thermoanaerobacter thermohydrosulfuricus exhibiting maltodextrinohydrolase activity. | an alpha-glucosidase with the ability to attack polymeric substrates was purified to homogeneity from culture supernatants of thermoanaerobacter thermohydrosulfuricus dsm 567. the enzyme is apparently a glycoprotein with a molecular mass of 160 kda. maximal activity is observed between ph5 and 7 at 75 degrees c. the alpha-glucosidase is active towards p-nitrophenyl-alpha-d-glucoside, maltose, malto-oligosaccharides, starch and pullulan. highest activity is displayed towards the disaccharide malt ... | 1997 | 9371718 |
| immunoreactivity of allergen (bet v 1) conjugated to crystalline bacterial cell surface layers (s-layers). | crystalline cell surface layers (s-layers) from gram-positive eubacteria had been demonstrated as carrier/adjuvants for chemically synthesized tumor-associated oligosaccharide haptens and capsular polysaccharide antigens of streptococcus pneumoniae strains. | 1996 | 9373319 |
| the effects of temperature on the kinetics and stability of mesophilic and thermophilic 3-phosphoglycerate kinases. | the effects of temperature on the kinetic parameters kcat and km, for three isolates of the highly conserved monomeric enzyme 3-phosphoglycerate kinase (pgk), were investigated in detail using a rapid automated kinetics apparatus. pgk was purified from the thermophilic bacterium thermoanaerobacter sp. rt8.g4 (optimum growth temperature 68 degrees c), the mesophile zymomonas mobilis (optimum growth temperature 32 degrees c) and a second, unidentified, soil mesophile designated unid a (optimum gro ... | 1998 | 9494072 |
| cloning and characterization of transcription of the xylab operon in thermoanaerobacter ethanolicus. | the genes encoding xylose isomerase (xyla) and xylulose kinase (xylb) from the thermophilic anaerobe thermoanaerobacter ethanolicus were found to constitute an operon with the transcription initiation site 169 nucleotides upstream from the previously assigned (k. dekker, h. yamagata, k. sakaguchi, and s. udaka, agric. biol. chem. 55:221-227, 1991) promoter region. the bicistronic xylab mrna was processed by cleavage within the 5'-terminal portion of the xylb-coding sequence. transcription of xyl ... | 1998 | 9495747 |
| the mode of action of allicin: trapping of radicals and interaction with thiol containing proteins. | allicin (thio-2-propene-1-sulfinic acid s-allyl ester) is the main biologically active component of garlic clove extracts. its biological activity was attributed to either antioxidant activity or thiol disulfide exchange. antioxidant properties of both allicin and its precursor, alliin (+s-allyl-l-cysteine sulfoxide), were investigated in the fenton oxygen-radical generating system [h2o2-fe(ii)]. using the spin trapping technique and esr, it was found that both compounds possessed significant an ... | 1998 | 9528659 |
| chaperonins from thermoanaerobacter species. | | 1998 | 9534160 |
| the d-xylose-binding protein, xylf, from thermoanaerobacter ethanolicus 39e: cloning, molecular analysis, and expression of the structural gene. | immediately downstream from the thermoanaerobacter ethanolicus xylab operon, comprising genes that encode d-xylose isomerase and d-xylulose kinase, lies a 1,101-bp open reading frame that exhibits 61% amino acid sequence identity to the escherichia coli d-xylose binding periplasmic receptor, xylf, a component of the high-affinity binding-protein-dependent d-xylose transport. the 25-residue n-terminal fragment of the deduced t. ethanolicus xylf has typical features of bacterial leader peptides. t ... | 1998 | 9657999 |
| purification and characterization of thermostable pectate-lyases from a newly isolated thermophilic bacterium, thermoanaerobacter italicus sp. nov. | a novel thermophilic spore-forming anaerobic microorganism (strain ab9) able to grow on citrus pectin and polygalacturonic acid (pectate) was isolated from a thermal spa in italy. the newly isolated strain grows optimally at 70 degrees c with a growth rate of 0.23 h(-1) with pectin and 0.12 h(-1) with pectate as substrates. xylan, starch, and glycogen are also utilized as carbon sources and thermoactive xylanolytic (highest activity at 70 degrees - 75 degrees c), amylolytic as well as pullulolyt ... | 1997 | 9680298 |
| xylose transport by the anaerobic thermophile thermoanaerobacter ethanolicus and the characterization of a d-xylose-binding protein | thermoanaerobacter ethanolicus is a xylose-utilizing thermophilic anaerobe that produces considerable amounts of ethanol. a protein in xylose-growing cells was solubilized from cell membranes by extraction with octyl-beta-glucoside. internal peptide sequencing revealed that the protein was the product of a gene, xylf, encoding a putative d-xylose-binding protein. metabolic labeling with 14c palmitic acid suggested that this is a lipoprotein that is anchored to the cell membrane via a cysteine re ... | 1998 | 9767707 |
| anaerobaculum thermoterrenum gen. nov., sp. nov., a novel, thermophilic bacterium which ferments citrate. | a thermophilic anaerobic bacterium designated strain rwcit2t (t = type strain) was isolated from the production water of a petroleum reservoir. the cells of this organism are straight to slightly curved rods that are gram negative and nonmotile. spore formation has not been demonstrated. growth occurs at temperatures ranging from 28 to 60 degrees c, with optimum growth occurring at 55 degrees c, and at ph values ranging from 5.5 to 8.6, with optimum growth occurring between ph 7 and 7.6. growth ... | 1997 | 8995817 |
| sequence analysis and heterologous expression of the groe genes from thermoanaerobacter sp. rt8.g4. | the groe homologous genes of the anaerobic thermophile thermoanaerobacter sp. rt8.g4 (trt) have been isolated, sequenced and analysed. the trt groes and groel encode subunits of chaperonin 10 (cpn10) and chaperonin 60 (cpn60) of 94 and 541 amino acids, respectively, and are arranged in that order forming the open reading frames (orfs) of a bicistronic operon. a controlling inverted repeat of chaperone expression (circe) element lies between the consensus promoter of the operon and trt groes. at ... | 1998 | 9795109 |
| a kinetic locking-on strategy for bioaffinity purification: further studies with alcohol dehydrogenase. | the kinetic locking-on strategy improves the selectivity of protein purification procedures based on immobilized cofactor derivatives through use of enzyme-specific substrate analogues in irrigants to promote biospecific adsorption. this paper describes the development and application of this strategy to the one-chromatographic step affinity purification of nad(p)+-dependent alcohol dehydrogenases using 8'-azo-linked immobilized nad(p)+, s6-linked and n6-linked immobilized nad+, and n6-linked im ... | 1999 | 10024480 |
| effect of chemical modification of cyclodextrin glycosyltransferase (cgtase) from thermoanaerobacter sp. on its activity and product selectivity. | | 1998 | 10075634 |
| chemical modification of lysine side chains of cyclodextrin glycosyltransferase from thermoanaerobacter causes a shift from cyclodextrin glycosyltransferase to alpha-amylase specificity. | cyclodextrin glycosyltransferases and alpha-amylases are two groups of enzymes with related secondary structures. however, cyclodextrin glycosyltransferases display transferase activities not present in alpha-amylases, probably derived from the existence of two more domains and different amino acid sequences. the hydrolytic activity of cyclodextrin glycosyltransferases is generally quite low, except for two cyclodextrin glycosyltransferases from termophiles. in this work, we have carried out the ... | 1999 | 10094484 |
| oligomeric integrity--the structural key to thermal stability in bacterial alcohol dehydrogenases. | principles of protein thermostability have been studied by comparing structures of thermostable proteins with mesophilic counterparts that have a high degree of sequence identity. two tetrameric nadp(h)-dependent alcohol dehydrogenases, one from clostridium beijerinckii (cbadh) and the other from thermoanaerobacter brockii (tbadh), having exceptionally high (75%) sequence identity, differ by 30 degrees in their melting temperatures. the crystal structures of cbadh and tbadh in their holo-enzyme ... | 1999 | 10417229 |
| thermoanaerobacter siderophilus sp. nov., a novel dissimilatory fe(iii)-reducing, anaerobic, thermophilic bacterium. | a thermophilic, anaerobic, spore-forming, dissimilatory fe(iii)-reducing bacterium, designated strain sr4t, was isolated from sediment of newly formed hydrothermal vents in the area of the eruption of karymsky volcano on the kamchatka peninsula. cells of strain sr4t were straight-to-curved, peritrichous rods, 0.4-0.6 micron in diameter and 3.5-9.0 microns in length, and exhibited a slight tumbling motility. strain sr4t formed round, refractile, heat-resistant endospores in terminally swollen spo ... | 1999 | 10555328 |
| organization and sequence of histidine biosynthesis genes hish, -a, -f, and -ie in thermoanaerobacter ethanolicus. | nucleotide sequence analysis of a 3.5-kb chromosomal fragment from the low g + c gram-positive bacterium thermoanaerobacter ethanolicus revealed a cluster of five contiguous open reading frames (orfs) designated hish, hisa, hisf, hisie, and orf5. the first four orfs showed homology to genes of the histidine biosynthesis pathway, and orf5 encoded a product with no significant similarities to polypeptides presently known. the hish orf was partial (truncated by cloning) and orf5 was adjacent to xyl ... | 2000 | 10594232 |
| crystal structure of a thermophilic alcohol dehydrogenase substrate complex suggests determinants of substrate specificity and thermostability. | the crystal structure of a thermophilic alcohol dehydrogenase (tbad) from thermoanaerobacter brockii has been determined in a binary complex with sec-butanol as substrate to a resolution of 3.0 a. van der waals interactions of the carbon c1 atom of sec-butanol with atoms in his59, ala85, trp110, asp150, and leu294 account for the substrate preference of this enzyme for secondary over primary alcohols. a crevice from the surface to the active site provides access for substrates and products. this ... | 1999 | 10651277 |
| culture-dependent and culture-independent characterization of microbial assemblages associated with high-temperature petroleum reservoirs. | recent investigations of oil reservoirs in a variety of locales have indicated that these habitats may harbor active thermophilic prokaryotic assemblages. in this study, we used both molecular and culture-based methods to characterize prokaryotic consortia associated with high-temperature, sulfur-rich oil reservoirs in california. enrichment cultures designed for anaerobic thermophiles, both autotrophic and heterotrophic, were successful at temperatures ranging from 60 to 90 degrees c. heterotro ... | 2000 | 10653739 |