| cloning and nucleotide sequence of a heat-stable amylase gene from an anaerobic thermophile, dictyoglomus thermophilum. | a highly heat-stable amylase gene from an obligately anaerobic and extremely thermophilic bacterium, dictyoglomus thermophilum, was cloned and expressed in escherichia coli. the nucleotide sequence of the amylase gene predicts a 686-amino-acid protein of relative molecular mass 81,200, which is consistent with that determined by sodium dodecyl sulfate/polyacrylamide gel electrophoresis of the purified enzyme. the nh2-terminal sequence determined using the enzyme purified from e. coli cells corre ... | 1988 | 2453362 |
| cloning and expression in escherichia coli of two additional amylase genes of a strictly anaerobic thermophile, dictyoglomus thermophilum, and their nucleotide sequences with extremely low guanine-plus-cytosine contents. | an obligately anaerobic and extremely thermophilic bacterium, dictyoglomus thermophilum, produces multiple extracellular amylases. in addition to one of the amylase genes, amya, which we previously cloned and characterized, we have cloned two additional genes, amyb and amyc, coding for amylases of this thermophile, into escherichia coli and determined their nucleotide sequences. the two amylase genes were expressed under the control of e. coli promoters. almost all activity was detected in the i ... | 1988 | 2458257 |
| alpha-amylase from the hyperthermophilic archaebacterium pyrococcus furiosus. cloning and sequencing of the gene and expression in escherichia coli. | a gene encoding a highly thermostable alpha-amylase from the hyperthermophilic archaebacterium pyrococcus furiosus was cloned and expressed in escherichia coli. the nucleotide sequence of the gene predicts a 649-amino acid protein with a calculated molecular mass of 76.3 kda, which corresponds well with the value obtained from purified enzyme using denaturing polyacrylamide gel electrophoresis. the nh2 terminus of the deduced amino acid sequence corresponds precisely to that obtained from the pu ... | 1993 | 8226990 |
| cloning, sequencing, and expression of a xylanase gene from the extreme thermophile dictyoglomus thermophilum rt46b.1 and activity of the enzyme on fiber-bound substrate. | a genomic library of the dictyoglomus sp. strain rt46b.1 was constructed in the phage vector lambda zapii and screened for xylanase activity. a plaque expressing xylanase activity, designated b6-77, was isolated and shown to contain a genomic insert of 5.3 kb. subcloning revealed that the xylanase activity was restricted to a internal 1,507-bp psti-hindiii fragment which was subsequently sequenced and shown to contain a single complete open reading frame coding for a single-domain xylanase, xyna ... | 1995 | 8534104 |
| close evolutionary relatedness among functionally distantly related members of the (alpha/beta)8-barrel glycosyl hydrolases suggested by the similarity of their fifth conserved sequence region. | a short conserved sequence equivalent to the fifth conserved sequence region of alpha-amylases (173_lpdld, aspergillus oryzae alpha-amylase) comprising the calcium-ligand aspartate, asp-175, was identified in the amino acid sequences of several members of the family of (alpha/beta)8-barrel glycosyl hydrolases. despite the fact that the aspartate is not invariantly conserved, the stretch can be easily recognised in all sequences to be positioned 26-28 amino acid residues in front of the well-know ... | 1995 | 8543020 |
| sequencing, cloning and expression of a beta-1,4-mannanase gene, mana, from the extremely thermophilic anaerobic bacterium, caldicellulosiruptor rt8b.4. | a gene encoding a beta-mannanase (mana) has been cloned from an obligately anaerobic extreme thermophile, caldicellulosiruptor strain rt8b.4, which is most closely related to caldicellulosiruptor saccharolyticus (formerly caldocellum saccharolyticum). the gene codes for a multidomain enzyme with a c-terminal beta-mannanase domain which was amplified by the polymerase chain reaction and cloned into a temperature-inducible expression vector in escherichia coli. sequence comparisons have shown that ... | 1996 | 8764509 |
| 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 |
| expression and secretion of a thermostable bacterial xylanase in kluyveromyces lactis. | the xyna structural gene from the extremely thermophilic anaerobe dictyoglomus thermophilum rt46b.1 was fused in frame with the secretion signal of the kluyveromyces lactis killer toxin in episomal expression vectors based on the kluyveromyces plasmid pkd1. xyna was secreted predominantly as an unglycosylated 35-kda protein which comprised up to 90% of the total extracellular proteins and reached a concentration of 130 micrograms/ml in shake-flask cultures grown under selective conditions. | 1997 | 9251219 |
| cloning, sequencing, and expression of the gene encoding amylopullulanase from pyrococcus furiosus and biochemical characterization of the recombinant enzyme. | the gene encoding the pyrococcus furiosus hyperthermophilic amylopullulanase (apu) was cloned, sequenced, and expressed in escherichia coli. the gene encoded a single 827-residue polypeptide with a 26-residue signal peptide. the protein sequence had very low homology (17 to 21% identity) with other apus and enzymes of the alpha-amylase family. in particular, none of the consensus regions present in the alpha-amylase family could be identified. p. furiosus apu showed similarity to three proteins, ... | 1997 | 9293009 |
| 4-alpha-glucanotransferase from the hyperthermophilic archaeon thermococcus litoralis--enzyme purification and characterization, and gene cloning, sequencing and expression in escherichia coli. | 4-alpha-glucanotransferase was purified from cells of thermococcus litoralis, a hyperthermophilic archaeon. the molecular mass of the enzyme was estimated to be approximately 87 kda by gel filtration. the optimal temperature for its activity was 90 degrees c. the enzyme catalyzed the transglycosylation of maltooligosaccharides, yielding maltooligosaccharides of various lengths and glucose. when maltoheptaose was used as the substrate, glucoamylase-resistant and glucoamylase-sensitive saccharides ... | 1997 | 9310375 |
| cloning of the xynb gene from dictyoglomus thermophilum rt46b.1 and action of the gene product on kraft pulp. | a two-step pcr protocol was used to identify and sequence a family 11 xylanase gene from dictyoglomus thermophilum rt46b.1. family 11 xylanase consensus fragments (gxcfs) were amplified from rt46b.1 genomic dna by using different sets of consensus pcr primers that exhibited broad specificity for conserved motifs within fungal and/or bacterial family 11 xylanase genes. on the basis of the sequences of a representative sample of the gxcfs a single family 11 xylanase gene (xynb) was identified. the ... | 1998 | 9572948 |
| family 10 and 11 xylanase genes from caldicellulosiruptor sp. strain rt69b.1. | three family 10 xylanase genes (xyna, xynb, and xync) and a single family 11 xylanase gene (xynd) were identified from the extreme thermophile caldicellulosiruptor strain rt69b.1 through the use of consensus pcr in conjunction with sequencing and polyacrylamide gel electrophoresis. these genes appear to comprise the complete endoxylanase system of rt69b.1. the xyna gene was found to be homologous to the xyna gene of the closely related caldicellulosiruptor strain rt8b.4, and primers designed pre ... | 1999 | 10356996 |
| purification and properties of the pyrophosphate-dependent phosphofructokinase from dictyoglomus thermophilum rt46 b.1. | the distribution of phosphofructokinase phosphoryl donor subtypes (atp-, adp-, and pyrophosphate) in the deeply rooted phylogenetic lineages of thermophiles is of interest with regard to the evolution of phosphofructokinase activity and of the embden-meyerhof pathway. in this article we present the first biochemical description of a thermostable pyrophosphate-dependent phosphofructokinase from the hyperthermophilic bacterium dictyoglomus thermophilum. the enzyme was not allosterically controlled ... | 1999 | 10356999 |
| sequencing and expression of a beta-mannanase gene from the extreme thermophile dictyoglomus thermophilum rt46b.1, and characteristics of the recombinant enzyme. | a beta-mannanase gene (mana) was isolated from the extremely thermophilic bacterium dictyoglomus thermophilum rt46b.1. mana is a single-domain enzyme related to one group of beta-mannanases (glycosyl hydrolase family 26). the mana gene was expressed in the heat-inducible vector pjla602 and the expression product, mana, purified to homogeneity. the recombinant mana is a monomeric enzyme with a molecular mass of 40 kda and an optimal temperature and ph for activity of 80 degrees c and 5.0. in the ... | 1999 | 10525841 |
| sequencing, cloning, and high-level expression of the pfp gene, encoding a pp(i)-dependent phosphofructokinase from the extremely thermophilic eubacterium dictyoglomus thermophilum. | the sequencing, cloning, and expression of the pfp gene from dictyoglomus thermophilum, which consists of 1,041 bp and encodes a pyrophosphate-dependent phosphofructokinase, are described. a phylogenetic analysis indicates that the enzyme is closely related to the pyrophosphate-dependent enzyme from thermoproteus tenax. the recombinant and native enzymes share a high degree of similarity for most properties examined. | 2000 | 10913106 |
| codon optimization of xylanase gene xynb from the thermophilic bacterium dictyoglomus thermophilum for expression in the filamentous fungus trichoderma reesei. | the catalytic domain of the xynb (xylanase) gene from the thermophilic bacterium dictyoglomus thermophilum was reconstructed by pcr to match the codon preference of trichoderma reesei. the 0.6-kb dna fragment encoding the enzyme was first amplified by primer extension with a mixture of eight overlapping oligonucleotides, followed by pcr with outside primers containing restriction enzyme sites for directional cloning into escherichia coli and t. reesei vectors. the synthetic gene was expressed in ... | 2000 | 10981683 |
| structure of xynb, a highly thermostable beta-1,4-xylanase from dictyoglomus thermophilum rt46b.1, at 1.8 a resolution. | microorganisms employ a large array of enzymes to break down the cellulose and hemicelluloses of plant biomass. these enzymes, especially those with high thermal stability, have many uses in biotechnology. we have solved the crystal structure of a beta-1, 4-xylanase, xynb, from the extremely thermophilic bacterium dictyoglomus thermophilum, isolate rt46b.1. the protein crystallized from 1.6 m ammonium sulfate, 0.2 m hepes ph 7.2 and 10% glycerol, with unit-cell parameters a = b = 91.3, c = 44.9 ... | 2000 | 11053833 |
| polyamines of the thermophilic eubacteria belonging to the genera thermosipho, thermaerobacter and caldicellulosiruptor. | cellular polyamines of four new thermophiles located in three early branched eubacterial clades, were investigated for the chemotaxonomic significance of polyamine distribution profiles. the thermophilic anaerobic thermosipho japonicus, belonging to the order thermotogales, contained norspermidine, norspermine and thermospermine in addition to spermidine and spermine. the polyamine profile was identical to the polyamine composition of thermotoga, fervidobacterium and petrotoga species of the ord ... | 2001 | 11327112 |
| expression of xylanase enzymes from thermophilic microorganisms in fungal hosts. | bulk production of xylanases from thermophilic microorganisms is a prerequisite for their use in industrial processes. as effective secretors of gene products, fungal expression systems provide a promising, industrially relevant alternative to bacteria for heterologous enzyme production. we are currently developing the yeast kluyveromyces lactis and the filamentous fungus trichoderma reesei for the extracellular production of thermophilic enzymes for the pulp and paper industry. the k. lactis sy ... | 2002 | 12072952 |
| recombinant enzymes from thermophilic micro-organisms expressed in fungal hosts. | cost-effective production of enzymes for industrial processes makes the appropriate selection of the host/vector expression system critical. we have tested two fungal systems for the bulk production of enzymes from thermophiles. the yeast kluyveromyces lactis has been developed as a secretion host employing expression vectors based on the 2u-like plasmid pkd1 of kluyveromyces drosophilarium. our second system involves the filamentous fungus trichoderma reesei. signal and protein fusion vectors h ... | 2004 | 15046592 |
| transglycosylation activity of dictyoglomus thermophilum amylase a. | amylase a from dictyoglomus thermophilum is a thermophilic enzyme and has about 40% identity with 4-alpha-glucanotransferase (gtase) from thermococcus litoralis, and both of these enzymes belong to family 57 glycosyl hydrolase. since the transglycosylation activity of t. litoralis gtase has been well characterized, the substrate specificity and reaction products of amylase a from d. thermophilum were examined. alpha-1,4 glucan was produced from maltooligosaccharides, and glucoamylase-resistant m ... | 2004 | 15564678 |
| heat-resistant oxygen-carrying hemoproteins consist of recombinant xylanases and synthetic iron(ii) porphyrin. | synthetic iron(ii) porphyrin (fep) is equivalently incorporated into recombinant thermotoga maritima xylanase b (tmx; family f/10 of glycoside hydrolase), producing a heat-resistant artificial hemoprotein (tmx-fep) that can bind and release oxygen (o(2)) in aqueous medium (ph 7.3, 25 degrees c) in the same manner as hemoglobin and myoglobin. the oxygenated species was sufficiently stable; the half-lifetime against the ferric state (tau(1/2)) was 5 h. this o(2)-carrying hemoprotein showed a high ... | 2005 | 15877369 |
| aminobacterium colombiensegen. nov. sp. nov., an amino acid-degrading anaerobe isolated from anaerobic sludge. | a new gram-negative, non-sporulating, mesophilic, amino acid fermenting bacterium, designated strain ala-1(t) (t = type strain), was isolated from an anaerobic lagoon of a dairy wastewater treatment plant. the strain is curved (3-4 microm x 0.2-0.3 microm) and occurs singly or in pairs. optimum growth occurs at 37 degrees c and ph 7.3. the g+c content of the dna is 46 mol %. the strain requires yeast extract for growth, grows poorly on casamino acids, peptones, cysteine, and alpha-ketoglutarate, ... | 1998 | 16887649 |
| bioaugmentation of a two-stage thermophilic (68 degrees c/55 degrees c) anaerobic digestion concept for improvement of the methane yield from cattle manure. | the possibility of improving a two-stage (68 degrees c/55 degrees c) anaerobic digestion concept for treatment of cattle manure was studied. in batch experiments, a 10-24% increase of the specific methane yield from cattle manure and its fractions was obtained, when the substrates were inoculated with bacteria of the genus caldicellusiruptor and dictyoglomus. in a reactor experiment inoculation of a 68 degrees c pretreatment reactor with caldicellusiruptor resulted in a 93% increase in the metha ... | 2007 | 17252605 |
| biodiversity of thermophilic prokaryotes with hydrolytic activities in hot springs of uzon caldera, kamchatka (russia). | samples of water from the hot springs of uzon caldera with temperatures from 68 to 87 degrees c and phs of 4.1 to 7.0, supplemented with proteinaceous (albumin, casein, or alpha- or beta-keratin) or carbohydrate (cellulose, carboxymethyl cellulose, chitin, or agarose) biological polymers, were filled with thermal water and incubated at the same sites, with the contents of the tubes freely accessible to the hydrothermal fluid. as a result, several enrichment cultures growing in situ on different ... | 2009 | 18978089 |
| temperature influence on fluorescence intensity and enzyme activity of the fusion protein of gfp and hyperthermophilic xylanase. | by constructing the expression system for fusion protein of gfpmut1 (a green fluorescent protein mutant) with the hyperthermophilic xylanase obtained from dictyoglomus thermophilum rt46b.1, the effects of temperature on the fluorescence of gfp and its relationship with the activities of gfp-fused xylanase have been studied. the fluorescence intensities of both gfp and gfp-xylanase have proved to be thermally sensitive, with the thermal sensitivity of the fluorescence intensity of gfp-xylanase be ... | 2009 | 19390851 |
| expression and characterization of the dictyoglomus thermophilum rt46b.1 xylanase gene (xynb) in bacillus subtilis. | to obtain extracellular and high-level expression of the dictyoglomus thermophilum rt46b.1 xylanase b gene, this gene was integrated into the alpha-amylase gene site of a host strain of bacillus subtilis wb800. the extreme thermophile xylanase gene was successfully integrated and expressed in the host, measured at 24 + or - 0.4 xus/ml in the luria broth medium supernatant. the recombinant enzyme was purified by ammonium sulfate precipitation, anion exchange chromatography, and gel filtration. th ... | 2010 | 19430737 |
| autohydrolysis of plant xylans by apoplastic expression of thermophilic bacterial endo-xylanases. | the genes encoding the two endo-xylanases xyna and xynb from the thermophilic bacterium dictyoglomus thermophilum were codon optimized for expression in plants. both xylanases were designed to be constitutively expressed under the control of the camv 35s promoter and targeted to the apoplast. transient expression in tobacco and stable expression in transgenic arabidopsis showed that both enzymes were expressed in an active form with temperature optima at 85 degrees c. transgenic arabidopsis accu ... | 2010 | 20384855 |
| alteration of the ph optimum of a family 11 xylanase, xynb6 of dictyoglomus thermophilum. | we reported previously that the activities of several glycosyl hydrolase family 11 xylanases claimed to be active under alkaline conditions, were found to have optima in the ph 5-6 range when assayed under optimal conditions. one enzyme, badx, had enhanced activity at phs greater than 7 compared to other family 11 xylanases. gene shuffling between badx and dictyoglomus thermophilum xynb6 was performed in an attempt to elucidate regions conferring alkaline activity to badx, and potentially, to in ... | 2010 | 20601267 |
| mining dictyoglomus turgidum for enzymatically active carbohydrases. | the genome of dictyoglomus turgidum was sequenced and analyzed for carbohydrases. the broad range of carbohydrate substrate utilization is reflected in the high number of glycosyl hydrolases, 54, and the high percentage of cazymes present in the genome, 3.09% of its total genes. screening a random clone library generated from d. turgidum resulted in the discovery of five novel biomass-degrading enzymes with low homology to known molecules. whole genome sequencing of the organism followed by bioi ... | 2011 | 20635162 |
| anaerobic transformation of carbon monoxide by microbial communities of kamchatka hot springs. | carbon monoxide (co) is one of the common gaseous compounds found in hot volcanic environments. it is known to serve as the growth substrate for a number of thermophilic prokaryotes, both aerobic and anaerobic. the goal of this work was to study the process of anaerobic transformation of co by microbial communities inhabiting natural thermal environments: hot springs of uzon caldera, kamchatka. the anaerobic microbial community of treshchinny spring (80-¦c, ph 6.5) was found to exhibit two peaks ... | 2011 | 21387195 |
| phylogeny and molecular signatures for the phylum thermotogae and its subgroups. | thermotogae species are currently identified mainly on the basis of their unique toga and distinct branching in the rrna and other phylogenetic trees. no biochemical or molecular markers are known that clearly distinguish the species from this phylum from all other bacteria. the taxonomic/evolutionary relationships within this phylum, which consists of a single family, are also unclear. we report detailed phylogenetic analyses on thermotogae species based on concatenated sequences for many ribos ... | 2011 | 21503713 |
| whole-genome comparison clarifies close phylogenetic relationships between the phyla dictyoglomi and thermotogae. | the anaerobic thermophilic bacterial genus dictyoglomus is characterized by the ability to produce useful enzymes such as amylase, mannanase, and xylanase. despite the significance, the phylogenetic position of dictyoglomus has not yet been clarified, since it exhibits ambiguous phylogenetic positions in a single gene sequence comparison-based analysis. the number of substitutions at the diverging point of dictyoglomus is insufficient to show the relationships in a single gene comparison-based a ... | 2011 | 21851855 |
| characterization of a gh3 family β-glucosidase from dictyoglomus turgidum and its application to the hydrolysis of isoflavone glycosides in spent coffee grounds. | a recombinant β-glucosidase from dictyoglomus turgidum was purified with a specific activity of 31 u/mg by his-trap affinity chromatography. d. turgidum β-glucosidase was identified as a memmber of the glycoside hydrolase (gh) 3 family on the basis of its amino acid sequence. the native enzyme existed as an 86 kda monomer with an activity maximum at ph 5 and 85 °c with a half-life of 334 min. the hydrolytic activity of the enzyme with aryl-glycoside substrates was the highest for p-nitrophenyl ( ... | 2011 | 21919440 |