| overproduction of an acetylxylan esterase from the extreme thermophile "caldocellum saccharolyticum" in escherichia coli. | the xync gene coding for an acetylxylan esterase from the extreme thermophile "caldocellum saccharolyticum" was overexpressed in escherichia coli strain rr28 by cloning the gene downstream from the lacz promoter region of puc18 (pnz1447) or downstream from the temperature-inducible lambda prpl promoters of pjla602 (pnz1600). the protein formed high molecular weight aggregates in induced cells of rr28/pnz1600 but not in rr28/pnz1447. the enzyme constituted up to 10% of the total cell protein and ... | 1990 | 1367035 |
| in vitro mutagenesis of a xylanase from the extreme thermophile caldocellum saccharolyticum. | six mutant xylanases were obtained by in vitro mutagenesis of a xylanase gene from the extremely thermophilic bacterium caldocellum saccharolyticum. the temperature stability of all enzymes was affected by mutation to various degrees and one of the xylanases had an altered temperature optimum. the mutations had no effect on the ph optimum. the c. saccharolyticum xylanase showed strong homology to several thermophilic and mesophilic xylanases, and comparison of primary sequences allowed the local ... | 1992 | 1368204 |
| the beta-mannanase from "caldocellum saccharolyticum" is part of a multidomain enzyme. | the complete sequence of a beta-mannanase gene from an anaerobic extreme thermophile was determined, and it shows that the expressed protein consists of two catalytic domains and two binding domains separated by spacer regions rich in proline and threonine residues. the amino-terminal catalytic domain has beta-mannanase activity, and the carboxy-terminal domain acts as an endoglucanase. neither domain shows homology with any other cellulase or hemicellulase sequence at the nucleic acid or protei ... | 1992 | 1476429 |
| a bifunctional xylanase encoded by the xyna gene of the rumen cellulolytic bacterium ruminococcus flavefaciens 17 comprises two dissimilar domains linked by an asparagine/glutamine-rich sequence. | the nucleotide sequence of the xyna gene of ruminococcus flavefaciens 17 was determined and found to consist of a 2862bp open reading frame beginning with a ttg start codon. the predicted product, xyla, consisted of distinct amino-terminal (a) and carboxy terminal (c) domains (248 amino acids, including a putative signal sequence, and 332 amino acids, respectively) linked by a repetitive sequence (b, 374 amino acids) extraordinarily rich in asparagine (45%) and glutamine (26%) residues. domains ... | 1992 | 1584021 |
| purification and properties of an aryl beta-xylosidase from a cellulolytic extreme thermophile expressed in escherichia coli. | an aryl beta-xylosidase was purified to homogeneity from an escherichia coli strain containing a recombinant plasmid carrying a beta-xylosidase (ec 3.2.1.37) gene from the extremely thermophilic anaerobic bacterium isolate tp8t6.3.3.1 ('caldocellum saccharolyticum'). it has a pi of 4.3 and shows optimal activity at ph 5.7. the enzyme is highly specific, acting on o- and p-nitrophenyl beta-d-xylopyranosides and minimally on p-nitrophenyl alpha-l-arabinopyranoside. it does not act on xylobiose. th ... | 1991 | 1847618 |
| cloning, sequencing and expression of a gene encoding a 73 kda xylanase enzyme from the rumen anaerobe butyrivibrio fibrisolvens h17c. | the cloning, expression and nucleotide sequence of a 3 kb dna segment on pls206 containing a xylanase gene (xynb) from butyrivibrio fibrisolvens h17c was investigated. the open reading frame (orf) of 1905 bp encoded a xylanase of 635 amino acid residues (mr 73156). at least 850 bp at the 3' end of the gene could be deleted without loss of xylanase activity. the deduced amino acid sequence was confirmed by purifying the enzyme and subjecting it to n-terminal amino acid sequence analysis. in esche ... | 1991 | 1909424 |
| sequence homology between a beta-galactosidase and some beta-glucosidases. | a significant sequence homology was found between a thermostable beta-galactosidase from sulfolobus solfataricus and two beta-glucosidases, respectively, from caldocellum saccharolyticum and from agrobacterium sp. these glycosidases appear to form a new protein family, since no homology could be detected with established beta-galactosidase or beta-glucosidase families. | 1991 | 1924272 |
| cloning, sequence analysis, and expression in escherichia coli of a gene coding for a beta-mannanase from the extremely thermophilic bacterium "caldocellum saccharolyticum". | a lambda recombinant phage expressing beta-mannanase activity in escherichia coli has been isolated from a genomic library of the extremely thermophilic anaerobe "caldocellum saccharolyticum." the gene was cloned into pbr322 on a 5-kb bamhi fragment, and its location was obtained by deletion analysis. the sequence of a 2.1-kb fragment containing the mannanase gene has been determined. one open reading frame was found which could code for a protein of mr 38,904. the mannanase gene (mana) was over ... | 1991 | 2039230 |
| cloning, sequence analysis, and expression of genes encoding xylan-degrading enzymes from the thermophile "caldocellum saccharolyticum". | a lambda recombinant bacteriophage coding for xylanase and beta-xylosidase activity has been isolated from a genomic library of the extremely thermophilic anaerobe "caldocellum saccharolyticum." partial sau3ai fragments of the lambda recombinant dna were ligated into pbr322. a recombinant plasmid with an insertion of ca. 7 kilobases of thermophilic dna expressing both enzymatic activities was isolated. the location of the genes has been established by analyzing deletion derivatives, and the dna ... | 1990 | 2111111 |
| celb, a gene coding for a bifunctional cellulase from the extreme thermophile "caldocellum saccharolyticum". | "caldocellum saccharolyticum" is an obligatory anaerobic thermophilic bacterium. a gene from this organism, designated celb, has been cloned in escherichia coli as part of a bacteriophage lambda gene library. this gene produces a thermostable cellulase that shows both endoglucanase and exoglucanase activities on test substrates and is able to degrade crystalline cellulose to glucose. the sequence of celb has homology with both exo- and endoglucanases described by others. it appears to have a cen ... | 1990 | 2126700 |
| sequence analysis of the clostridium stercorarium celz gene encoding a thermoactive cellulase (avicelase i): identification of catalytic and cellulose-binding domains. | the nucleotide sequence of the celz gene coding for a thermostable endo-beta-1,4-glucanase (avicelase i) of clostridium stercorarium was determined. the structural gene consists of an open reading frame of 2958 bp which encodes a preprotein of 986 amino acids with an mr of 109,000. the signal peptide cleavage site was identified by comparison with the n-terminal amino acid sequence of avicelase i purified from c. stercorarium culture supernatants. the recombinant protein expressed in escherichia ... | 1990 | 2250652 |
| xylanase from the extremely thermophilic bacterium "caldocellum saccharolyticum": overexpression of the gene in escherichia coli and characterization of the gene product. | a xylanase encoded by the xyna gene of the extreme thermophile "caldocellum saccharolyticum" was overexpressed in escherichia coli by cloning the gene downstream from the temperature-inducible lambda pr and pl promoters of the expression vector pjla602. induction of up to 55 times was obtained by growing the cells at 42 degrees c, and the xylanase made up to 20% of the whole-cell protein content. the enzyme was located in the cytoplasmic fraction in e. coli. the temperature and ph optima were de ... | 1990 | 2275529 |
| nucleotide sequence of a gene from caldocellum saccharolyticum encoding for exocellulase and endocellulase activity. | | 1989 | 2789517 |
| sequence structure and expression of a cloned beta-glucosidase gene from an extreme thermophile. | the gene for a beta-glucosidase from the extremely thermophilic bacterium caldocellum saccharolyticum has been isolated from a genomic library and sequenced. an open reading frame identified by computer analysis of the sequence could encode a protein of mr 54,400, which is close to the size of the polypeptide experimentally determined using maxicells. analysis of the amino-terminal residues of the protein produced in escherichia coli suggests that it is processed by a methionine aminopeptidase. ... | 1988 | 2851713 |
| optimising the recovery of recombinant thermostable proteins expressed in mesophilic hosts. | the purification of a thermostable caldocellum saccharolyticum beta-glucosidase expressed in escherichia coli was investigated using heat precipitation of unclarified cell homogenates. heat treatment at 70 degrees c was capable of purification with respect to cell debris, small particulates and the majority of cell protein, although e. coli proteins were even more efficiently removed at 80 degrees c and above. for thermostable proteins expressed in e. coli, a precipitation temperature of 80 degr ... | 1995 | 7576536 |
| cela, another gene coding for a multidomain cellulase from the extreme thermophile caldocellum saccharolyticum. | caldocellum saccharolyticum is an extremely thermophilic anaerobic bacterium capable of growth on cellulose and hemicellulose as sole carbon sources. cellulase and hemicellulase genes have been found clustered together on its genome. the gene for one of the cellulases (cela) was isolated on a lambda genomic library clone, sequenced and found to comprise a large open-reading frame of 5253 base pairs that could be translated into a peptide of 1751 amino acids. to date, it is the largest cellulase ... | 1995 | 7612247 |
| the effect of low temperatures on enzyme activity. | the stability of two enzymes from extreme thermophiles (glutamate dehydrogenase from thermococcales strain an1 and beta-glucosidase from caldocellum saccharolyticum expressed in escherichia coli) has been exploited to allow measurement of activity over a 175 degrees c temperature range, from +90 degrees c to -85 degrees c for the glutamate dehydrogenase and from +90 degrees c to -70 degrees c for the beta-glucosidase. the arrhenius plots of these enzymes, and those for two mesophilic enzymes (gl ... | 1995 | 7826325 |
| description of caldicellulosiruptor saccharolyticus gen. nov., sp. nov: an obligately anaerobic, extremely thermophilic, cellulolytic bacterium. | a new obligately anaerobic, extremely thermophilic, cellulolytic bacterium is described. the strain designated tp8t 6331 is differentiated from thermophilic cellulolytic clostridia on the basis of physiological characteristics and phylogenetic position within the bacillus/clostridium subphylum of the gram-positive bacteria. strain tp8t 6331 is assigned to a new genus caldicellulosiruptor, as caldicellulosiruptor saccharolyticus gen., nov., sp. nov. | 1994 | 8076802 |
| genetic organization, sequence and biochemical characterization of recombinant beta-xylosidase from thermoanaerobacterium saccharolyticum strain b6a-ri. | endoxylanase (xyna) and beta-xylosidase (xynb) genes from thermoanerobacterium saccharolyticum were subcloned from a cosmid clone (pxdm1) to generate pxph3. the nucleotide sequence of a psti-hindiii fragment in pxph3 that contained xynb revealed an open reading frame (orf) of 1500 bp encoding a 55 kda protein. another open reading frame (orf1) of unknown function was found 21 bp downstream from the first stop codon of xynb. xynb, orf1 and xyna had the same direction of transcription. xynb from t ... | 1993 | 8360617 |
| cloning and dna sequence of the gene coding for clostridium thermocellum cellulase ss (cels), a major cellulosome component. | clostridium thermocellum atcc 27405 produces an extracellular cellulase system capable of hydrolyzing crystalline cellulose. the enzyme system involves a multicomponent protein aggregate (the cellulosome) with a total molecular weight in the millions, impeding mechanistic studies. however, two major components of the aggregate, ss (m(r) = 82,000) and sl (m(r) = 250,000), which act synergistically to hydrolyze crystalline cellulose, have been identified (j. h. d. wu, w. h. orme-johnson, and a. l. ... | 1993 | 8444792 |
| purification and properties of a beta-1,4-xylanase from a cellulolytic extreme thermophile expressed in escherichia coli. | 1. an endoxylanase (ec 3.2.1.8) was purified from an escherichia coli strain carrying a xylanase gene from the extreme thermophile "caldocellum saccharolyticum" strain tp8t6.3.3.1. it was found to have an m(r) of 42,000 and an isoelectric point of approx. 5.0. 2. the enzyme showed optimum activity at ph 5.0-7.7 and had an activation energy of 44 kj mol-1. it was stable at room temperature at ph 4.5-11.5 in the presence of 0.5 mg ml-1 bovine serum albumin. the half-life of the enzyme at 75 degree ... | 1993 | 8467959 |
| 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 |
| comparison of a beta-glucosidase and a beta-mannosidase from the hyperthermophilic archaeon pyrococcus furiosus. purification, characterization, gene cloning, and sequence analysis. | two distinct exo-acting, beta-specific glycosyl hydrolases were purified to homogeneity from crude cell extracts of the hyperthermophilic archaeon pyrococcus furiosus: a beta-glucosidase, corresponding to the one previously purified by kengen et al. (kengen, s. w. m., luesink, e. j., stams, a. j. m., and zehnder, a. j. b. (1993) eur. j. biochem. 213, 305-312), and a beta-mannosidase. the beta-mannosidase and beta-glucosidase genes were isolated from a genomic library by expression screening. the ... | 1996 | 8798600 |
| cloning of a gene encoding cinnamoyl ester hydrolase from the ruminal bacterium butyrivibrio fibrisolvens e14 by a novel method. | a gene (cini) encoding a cinnamoyl ester hydrolase (ceh) has been isolated from the ruminal bacterium, butyrivibrio fibrisolvens e14, using a model substrate, mutmac [4-methylumbelliferoyl (p-trimethylammonium cinnamate chloride)]. cini has significant amino-acid similarities with members of a large and diverse family of hydrolases with a serine/aspartic acid/histidine catalytic triad. our analyses identified two previously unclassified amino acid sequences, the amino-terminal domain of unknown ... | 1996 | 8837463 |
| cloning, sequencing and overexpression in escherichia coli of a xylanase gene, xyna from the thermophilic bacterium rt8b.4 genus caldicellulosiruptor. | a genomic library of the extremely thermophilic eubacterial strain rt8b.4 was constructed in lambda zapii and screened for the expression of xylanase activity. one recombinant bacteriophage showed xylanase, xylosidase and arabinosidase activity. sequence analysis and homology comparisons showed that this plasmid derivative, pnz2011, was composed of 6.7 kb thermophilic dna and contained what appeared to be an operon-like structure involving genes associated with xylose metabolism. the xylanase ge ... | 1996 | 8920183 |
| cloning and sequence of a type i pullulanase from an extremely thermophilic anaerobic bacterium, caldicellulosiruptor saccharolyticus. | a gene coding for a pullulanase from the obligately anaerobic, extremely thermophilic bacterium caldicellulosiruptor saccharolyticus has been cloned in escherichia coli. it consists of an open reading frame (pula) of 2478 bp which codes for an enzyme of 95,732 da and is flanked by two other open reading frames. a truncated version of the gene which lacks 381 bp of 5'-sequence also has pullulanase activity and it appears that the amino-terminal portion of the gene is not essential for either acti ... | 1997 | 9375788 |
| properties and gene structure of a bifunctional cellulolytic enzyme (cela) from the extreme thermophile 'anaerocellum thermophilum' with separate glycosyl hydrolase family 9 and 48 catalytic domains. | a large cellulolytic enzyme (cela) with the ability to hydrolyse microcrystalline cellulose was isolated from the extremely thermophilic, cellulolytic bacterium 'anaerocellum thermophilum'. full-length cela and a truncated enzyme species designated cela' were purified to homogeneity from culture supernatants. cela has an apparent molecular mass of 230 kda. the enzyme exhibited significant activity towards avicel and was most active towards soluble substrates such as cm-cellulose (cmc) and beta-g ... | 1998 | 9493383 |
| caldicellulosiruptor owensensis sp. nov., an anaerobic, extremely thermophilic, xylanolytic bacterium. | an anaerobic, extremely thermophilic, xylanolytic, non-spore-forming bacterium was isolated from a sediment sample taken from owens lake, california, and designated strain olt (t = type strain). strain olt had a gramnegative reaction and occurred as short rods which sometimes formed long chains containing a few coccoid cells. it grew at 50-80 degrees c, with an optimum at 75 degrees c. the ph range for growth was 5.5-9.0 with an optimum at about ph 7.5. when grown on glucose at optimal condition ... | 1998 | 9542080 |
| 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 |
| caldicellulosiruptor kristjanssonii sp. nov., a cellulolytic, extremely thermophilic, anaerobic bacterium. | a cellulolytic anaerobic bacterium, strain 177r1bt, was isolated from a biomat sample of an icelandic, slightly alkaline, hot spring (78 degrees c). strain 177r1bt was rod-shaped, non-spore-forming, non-motile and stained gram-negative at all stages of growth. it grew at 45-82 degrees c, with an optimum growth temperature around 78 degrees c. at 70 degrees c, growth occurred at ph 5.8-8.0, with an optimum near ph 7.0. at the optimum temperature and ph, with 2 g cellobiose l-1 as substrate, strai ... | 1999 | 10425755 |
| polyhydroxylated pyrrolidine and pyrrolizidine alkaloids from hyancinthoides non-scripta and scilla campanulata. | aqueous ethanol extracts from the immature fruits and stalks of bluebell (hyacinthoides non-scripta) were subjected to various ion-exchange column chromatographic steps to give 1,4-dideoxy-1,4-imino-d-arabinitol (1),2(r),5(r)-bis(hydroxymethyl)-3(r),4(r)-dihydroxypyrrolidine (dmdp) (2), 6-deoxy-6-c-(2,5-dihydroxyhexyl)-dmdp (3),2,5-dideoxy-2,5-imino-dl-glycero-d-manno-heptitol (homodmdp)(4),homodmdp-7-o-apioside (5), homodmdp-7-o-beta-d-xylopyranoside (6), (1s*,2r*,3r*,5r*,7ar*)-1,2-dihydroxy-3, ... | 1999 | 10515698 |
| multidomain and multifunctional glycosyl hydrolases from the extreme thermophile caldicellulosiruptor isolate tok7b.1. | dna sequencing techniques have revealed widespread molecular diversity of the genomic organization of apparently closely related bacteria (as judged from ssu rdna sequence similarity). we have previously described the extreme thermophile caldicellulosiruptor saccharolyticus, which is unusual in possessing multi-catalytic, multidomain arrangements for the majority of its glycosyl hydrolases. we report here the sequencing of three gene clusters of glycosyl hydrolases from caldicellulosiruptor sp. ... | 2000 | 10706665 |
| synthesis and evaluation of aminocyclopentitol inhibitors of beta-glucosidases. | [reaction: see text] (1r,2s,3s,4r,5r)-4-amino-5-(hydroxymethyl)cyclopentane-1,2,3-triol 1, prepared from d-glucose, inhibits beta-glucosidases from caldocellum saccharolyticum (ki = 1.8 x 10(-7) m) and from almonds (ki = 3.4 x 10(-6) m). inhibition is not influenced by n-ethylation (--> 15) but is strongly reduced upon n-acetylation (--> 12). inversion of stereochemistry at c(5) (--> 14) has little effect on inhibition of beta-glucosidases. these experiments suggest that 1 acts as an analogue of ... | 2000 | 10814269 |
| the c-disaccharide alpha-c(1-->3)-mannopyranoside of n-acetylgalactosamine is an inhibitor of glycohydrolases and of human alpha-1,3-fucosyltransferase vi. its epimer alpha-(1-->3)-mannopyranoside of n-acetyltalosamine is not. | the radical c-glycosidation of (-)-(1s,4r,5r, 6r)-6-endo-chloro-3-methylidene-5-exo-(phenylseleno)-7-ox abi cyclo[2. 2.1]heptan-2-one ((-)-4) with 2,3,4, 6-tetra-o-acetyl-alpha-d-mannopyranosyl bromide gave (+)-(1s,3r,4r, 5r,6r)-6-endo-chloro-5-exo-(phenylseleno)-3-endo-(1',3',4', 5'-tetra-o-acetyl-2', 6'-anhydro-7'-deoxy-d-glycero-d-manno-heptitol-7'-c-yl)-7-oxabi cyc lo[ 2.2.1]hept-2-one ((+)-5) that was converted into (+)-(1r,2s,5r, 6r)-5-acetamido-3-chloro-2-hydroxy-6-(1',3',4',5'-tetra-o-ac ... | 2000 | 10891123 |
| 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 |
| substrate and product inhibition of hydrogen production by the extreme thermophile, caldicellulosiruptor saccharolyticus. | substrate and product inhibition of hydrogen production during sucrose fermentation by the extremely thermophilic bacterium caldicellulosiruptor saccharolyticus was studied. the inhibition kinetics were analyzed with a noncompetitive, nonlinear inhibition model. hydrogen was the most severe inhibitor when allowed to accumulate in the culture. concentrations of 5-10 mm h(2) in the gas phase (identical with partial hydrogen pressure (ph(2)) of (1-2) x 10(4) pa) initiated a metabolic shift to lacta ... | 2003 | 12474247 |
| hydrogen production from paper sludge hydrolysate. | the main objective of this study was to develop a system for the production of "renewable" hydrogen. paper sludge is a solid industrial waste yielding mainly cellulose, which can be used, after hydrolysis, as a feedstock in anaerobic fermentation by (hyper)thermophilic organisms, such as thermotoga elfii and caldicellulosiruptor saccharolyticus. tests on different medium compositions showed that both bacteria were able to produce hydrogen from paper sludge hydrolysate, but the amount of produced ... | 2003 | 12721435 |
| yields from glucose, xylose, and paper sludge hydrolysate during hydrogen production by the extreme thermophile caldicellulosiruptor saccharolyticus. | this study addressed the utilization of an industrial waste stream, paper sludge, as a renewable cheap feedstock for the fermentative production of hydrogen by the extreme thermophile caldicellulosiruptor saccharolyticus. hydrogen, acetate, and lactate were produced in medium in which paper sludge hydrolysate was added as the sole carbon and energy source and in control medium with the same concentration of analytical grade glucose and xylose. the hydrogen yield was dependent on lactate formatio ... | 2004 | 15054273 |
| high-resolution crystal structures of caldicellulosiruptor strain rt8b.4 carbohydrate-binding module cbm27-1 and its complex with mannohexaose. | carbohydrate-binding modules (cbms) are the most common non-catalytic modules associated with enzymes active in plant cell-wall hydrolysis. despite the large number of putative cbms being identified by amino acid sequence alignments, only few representatives have been experimentally shown to have a carbohydrate-binding function. caldicellulosiruptor strain rt8b.4 man26 is a thermostable modular glycoside hydrolase beta-mannanase which contains two non-catalytic modules in tandem at its n terminu ... | 2004 | 15210353 |
| hydrolysis of beta-glucosyl ester linkage of p-hydroxybenzoyl beta-d-glucose, a chemically synthesized glucoside, by beta-glucosidases. | to investigate the hydrolysis of glucosyl esters by beta-glucosidase, p-hydroxybenzoyl beta-d-glucose (phbg) was chemically synthesized. the hydrolytic activity of some beta-glucosidases for phbg was compared to that for p-nitrophenyl beta-glucoside (pnpg). the clavibacter michiganense and flavobacterium johnsonae enzymes could hydrolyze phbg and steviol glycosides which are natural glucosyl esters. the commercial beta-glucosidase originating from caldocellum saccharolyticum also hydrolyzes phbg ... | 2000 | 16232920 |
| reclassification of thermoanaerobium acetigenum as caldicellulosiruptor acetigenus comb. nov. and emendation of the genus description. | although the type species of the genus thermoanaerobium, thermoanaerobium brockii, was transferred to thermoanaerobacter, thermoanaerobium acetigenum was not transferred. therefore, thermoanaerobium acetigenum should be reclassified. based on 16s rrna gene sequence analysis and re-examination of physiological properties of the type strain, x6b(t) (=dsm 7040(t) = atcc baa-1149(t)), we propose that thermoanaerobium acetigenum should be reclassified as caldicellulosiruptor acetigenus comb. nov. str ... | 2006 | 16738119 |
| glycolytic pathway and hydrogen yield studies of the extreme thermophile caldicellulosiruptor saccharolyticus. | nmr analysis of (13)c-labelling patterns showed that the embden-meyerhof (em) pathway is the main route for glycolysis in the extreme thermophile caldicellulosiruptor saccharolyticus. glucose fermentation via the em pathway to acetate results in a theoretical yield of 4 mol of hydrogen and 2 mol of acetate per mole of glucose. previously, approximately 70% of the theoretical maximum hydrogen yield has been reached in batch fermentations. in this study, hydrogen and acetate yields have been deter ... | 2007 | 17216445 |
| polysaccharide degradation and synthesis by extremely thermophilic anaerobes. | extremely thermophilic fermentative anaerobes (growth t(opt) > or = 70 degrees c) have the capacity to use a variety of carbohydrates as carbon and energy sources. as such, a wide variety of glycoside hydrolases and transferases have been identified in these microorganisms. the genomes of three model extreme thermophiles-an archaeon pyrococcus furiosus (t(opt) = 98 degrees c), and two bacteria, thermotoga maritima (t(opt) = 80 degrees c) and caldicellulosiruptor saccharolyticus (t(opt) = 70 degr ... | 2008 | 18378602 |
| caldicellulosiruptor kronotskyensis sp. nov. and caldicellulosiruptor hydrothermalis sp. nov., two extremely thermophilic, cellulolytic, anaerobic bacteria from kamchatka thermal springs. | five novel strains (2002(t), 2902, 2006, 108(t) and 117) of cellulose-degrading, anaerobic, thermophilic bacteria were isolated from terrestrial hot springs of kamchatka (far east, russia). strains 2002(t) and 108(t) were non-spore-forming bacteria with a gram-positive type cell wall and peritrichous flagella. optimum growth of strains 2002(t) and 108(t) occurred at ph 7.0 and at temperatures of 70 and 65 degrees c, respectively. the g+c contents of the dna of strains 2002(t) and 108(t) were 35. ... | 2008 | 18523201 |
| engineering cellulase mixtures by varying the mole fraction of thermomonospora fusca e5 and e3, trichoderma reesei cbhi, and caldocellum saccharolyticum beta-glucosidase. | in this study, different mole fractions of pure thermomonospora fusca e(5) and e(3), plus trichoderma reesei cbhi were studied for reducing sugar production at 2 h, degree of synergism, and cellulose binding. in addition, the effects of introducing the caldocellum saccharolyticum beta-glucosidase into this cellulase system were investigated. the cellulases used were purified to homogeneity. avicel ph 102 (4% w/w solution in 0.05 sodium acetate ph 5.5 buffer) was the substrate. reactions were run ... | 1993 | 18613229 |
| cloning and sequencing of the gene for cellobiose 2-epimerase from a ruminal strain of eubacterium cellulosolvens. | cellobiose 2-epimerase (ce; ec 5.1.3.11) is known to catalyze the reversible epimerization of cellobiose to 4-o-beta-d-glucopyranosyl-d-mannose in ruminococcus albus cells. here, we report a ce in a ruminal strain of eubacterium cellulosolvens for the first time. the nucleotide sequence of the ce had an orf of 1218 bp (405 amino acids; 46 963.3 da). the ce from e. cellulosolvens showed 44-54% identity to n-acyl-d-glucosamine 2-epimerase-like hypothetical proteins in the genomes of coprococcus eu ... | 2008 | 18710396 |
| hydrogenomics of the extremely thermophilic bacterium caldicellulosiruptor saccharolyticus. | caldicellulosiruptor saccharolyticus is an extremely thermophilic, gram-positive anaerobe which ferments cellulose-, hemicellulose- and pectin-containing biomass to acetate, co(2), and hydrogen. its broad substrate range, high hydrogen-producing capacity, and ability to coutilize glucose and xylose make this bacterium an attractive candidate for microbial bioenergy production. here, the complete genome sequence of c. saccharolyticus, consisting of a 2,970,275-bp circular chromosome encoding 2,67 ... | 2008 | 18776029 |
| 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 |
| performance and population analysis of a non-sterile trickle bed reactor inoculated with caldicellulosiruptor saccharolyticus, a thermophilic hydrogen producer. | non-axenic operation of a 400 l trickle bed reactor inoculated with the thermophile caldicellulosiruptor saccharolyticus, yielded 2.8 mol h2/mol hexose converted. the reactor was fed with a complex medium with sucrose as the main substrate, continuously flushed with nitrogen gas, and operated at 73 degrees c. the volumetric productivity was 22 mmol h2/(l filterbed h). acetic acid and lactic acid were the main by-products in the liquid phase. production of lactic acid occurred when hydrogen parti ... | 2009 | 19016484 |
| phylogenomic analyses of clostridia and identification of novel protein signatures that are specific to the genus clostridium sensu stricto (cluster i). | the species of clostridium comprise a very heterogeneous assemblage of bacteria that do not form a phylogenetically coherent group. it has been proposed previously that only a subset of the species of clostridium that form a distinct cluster in the 16s rrna tree (cluster i) should be regarded as the true representatives of the genus clostridium (i.e. clostridium sensu stricto). however, this cluster is presently defined only in phylogenetic terms, and no biochemical, molecular or phenotypic char ... | 2009 | 19196767 |
| genome sequence of the anaerobic, thermophilic, and cellulolytic bacterium "anaerocellum thermophilum" dsm 6725. | "anaerocellum thermophilum" dsm 6725 is a strictly anaerobic bacterium that grows optimally at 75 degrees c. it uses a variety of polysaccharides, including crystalline cellulose and untreated plant biomass, and has potential utility in biomass conversion. here we report its complete genome sequence of 2.97 mb, which is contained within one chromosome and two plasmids (of 8.3 and 3.6 kb). the genome encodes a broad set of cellulolytic enzymes, transporters, and pathways for sugar utilization and ... | 2009 | 19346307 |
| characterization of a thermostable endo-1,5-alpha-l-arabinanase from caldicellulorsiruptor saccharolyticus. | a recombinant putative glycoside hydrolase from caldicellulosiruptor saccharolyticus was purified with a specific activity of 12 u mg(-1) by heat treatment and his-trap affinity chromatography, and identified as a single 56 kda band upon sds-page. the native enzyme is a dimer with a molecular mass of 112 kda as determined by gel filtration. the enzyme exhibited its highest activity when debranched arabinan (1,5-alpha-l-arabinan) was used as the substrate, demonstrating that the enzyme was an end ... | 2009 | 19458916 |
| efficient degradation of lignocellulosic plant biomass, without pretreatment, by the thermophilic anaerobe "anaerocellum thermophilum" dsm 6725. | very few cultivated microorganisms can degrade lignocellulosic biomass without chemical pretreatment. we show here that "anaerocellum thermophilum" dsm 6725, an anaerobic bacterium that grows optimally at 75 degrees c, efficiently utilizes various types of untreated plant biomass, as well as crystalline cellulose and xylan. these include hardwoods such as poplar, low-lignin grasses such as napier and bermuda grasses, and high-lignin grasses such as switchgrass. the organism did not utilize only ... | 2009 | 19465524 |
| efficient hydrogen production from the lignocellulosic energy crop miscanthus by the extreme thermophilic bacteria caldicellulosiruptor saccharolyticus and thermotoga neapolitana. | the production of hydrogen from biomass by fermentation is one of the routes that can contribute to a future sustainable hydrogen economy. lignocellulosic biomass is an attractive feedstock because of its abundance, low production costs and high polysaccharide content. | 2009 | 19534765 |
| characterization of a recombinant beta-glucosidase from the thermophilic bacterium caldicellulosiruptor saccharolyticus. | a recombinant beta-glucosidase from caldicellulosiruptor saccharolyticus dsm 8903 with a specific activity of 13 u/mg was purified by heat treatment and his-trap affinity chromatography and identified as a single 54 kda band on sds-page. the molecular mass of the native enzyme was 108 kda as a dimer by gel filtration. beta-glucosidase showed optimum activity at ph 5.5 and 70 degrees c for p-nitrophenyl (pnp)-beta-d-glucopyranoside. the half-lives of the enzyme at 60, 70, and 80 degrees c were 25 ... | 2009 | 19577189 |
| fermentative hydrogen production from pretreated biomass: a comparative study. | the aim of this work was to evaluate the potential of employing biomass resources from different origin as feedstocks for fermentative hydrogen production. mild-acid pretreated and hydrolysed barley straw (bs) and corn stalk (cs), hydrolysed barley grains (bg) and corn grains (cg), and sugar beet extract (sb) were comparatively evaluated for fermentative hydrogen production. pretreatments and/or enzymatic hydrolysis led to 27, 37, 56, 74 and 45 g soluble sugars/100 g dry bs, cs, bg, cg and sb, r ... | 2009 | 19656677 |
| effects of galactose and glucose on the hydrolysis reaction of a thermostable beta-galactosidase from caldicellulosiruptor saccharolyticus. | a recombinant beta-galactosidase from caldicellulosiruptor saccharolyticus was purified with a specific activity of 211 u mg(-1) by using heat treatment and his-trap affinity chromatography. the native enzyme was an 80-kda trimer with a molecular mass of 240 kda. maximum activity was observed at ph 6.0 and 80 degrees c, and the half-life at 70 degrees c was 48 h. the enzyme exhibited hydrolytic activity for p-nitrophenyl-beta-d: -galactopyranoside (pnpgal), onpgal, or lactose, whereas no activit ... | 2010 | 19662397 |
| modular organisation and functional analysis of dissected modular beta-mannanase csman26 from caldicellulosiruptor rt8b.4. | csman26 from caldicellulosiruptor strain rt8.b4 is a modular beta-mannanase consisting of two n-terminal family 27 carbohydrate-binding modules (cbms), followed by a family 35 cbm and a family 26 glycoside hydrolase catalytic module (mannanase). a functional dissection of the full-length csman26 and a comprehensive characterisation of the truncated derivatives were undertaken to evaluate the role of the cbms. limited proteolysis was used to define biochemically the boundaries of the different st ... | 2010 | 19787349 |
| classification of 'anaerocellum thermophilum' strain dsm 6725 as caldicellulosiruptor bescii sp. nov. | the thermophilic, cellulolytic, anaerobic bacterium 'anaerocellum thermophilum' strain z-1320 was isolated from a hot spring almost two decades ago and deposited in the german collection of microorganisms and cell cultures (dsmz) as dsm 6725. the organism was classified as representing a new genus, 'anaerocellum', primarily on its growth physiology, cell-wall type and morphology. the results of recent physiological studies and of phylogenetic and genome sequence analyses of strain dsm 6725 of 'a ... | 2010 | 19801388 |
| carbohydrate utilization patterns for the extremely thermophilic bacterium caldicellulosiruptor saccharolyticus reveal broad growth substrate preferences. | coutilization of hexoses and pentoses derived from lignocellulose is an attractive trait in microorganisms considered for consolidated biomass processing to biofuels. this issue was examined for the h(2)-producing, extremely thermophilic bacterium caldicellulosiruptor saccharolyticus growing on individual monosaccharides (arabinose, fructose, galactose, glucose, mannose, and xylose), mixtures of these sugars, as well as on xylan and xylogluco-oligosacchrides. c. saccharolyticus grew at approxima ... | 2009 | 19820143 |
| directed evolution of a thermophilic beta-glucosidase for cellulosic bioethanol production. | characteristics that would make enzymes more desirable for industrial applications can be improved using directed evolution. we developed a directed evolution technique called random drift mutagenesis (rndm). mutant populations are screened and all functional mutants are collected and put forward into the next round of mutagenesis and screening. the goal of this technique is to evolve enzymes by rapidly accumulating mutations and exploring a greater sequence space by providing minimal selection ... | 2010 | 19834652 |
| characterization of a recombinant l-fucose isomerase from caldicellulosiruptor saccharolyticus that isomerizes l-fucose, d-arabinose, d-altrose, and l-galactose. | a recombinant l-fucose isomerase from caldicellulosiruptor saccharolyticus was purified as a single 68 kda band with an activity of 76 u mg(-1). the molecular mass of the native enzyme was 204 kda as a trimer. the maximum activity for l-fucose isomerization was at ph 7 and 75 degrees c in the presence of 1 mm mn(2+). its half-life at 70 degrees c was 6.1 h. for aldose substrates, the enzyme displayed activity in decreasing order for l-fucose, with a k (cat) of 11,910 min(-1) and a k (m) of 140 m ... | 2010 | 19856146 |
| caldicellulosiruptor obsidiansis sp. nov., an anaerobic, extremely thermophilic, cellulolytic bacterium isolated from obsidian pool, yellowstone national park. | a novel, obligately anaerobic, extremely thermophilic, cellulolytic bacterium, designated ob47(t), was isolated from obsidian pool, yellowstone national park, wy. the isolate was a nonmotile, non-spore-forming, gram-positive rod approximately 2 microm long by 0.2 microm wide and grew at temperatures between 55 and 85 degrees c, with the optimum at 78 degrees c. the ph range for growth was 6.0 to 8.0, with values of near 7.0 being optimal. growth on cellobiose produced the fastest specific growth ... | 2010 | 20023107 |
| lactate formation in caldicellulosiruptor saccharolyticus is regulated by the energy carriers pyrophosphate and atp. | caldicellulosiruptor saccharolyticus displays superior h(2) yields on a wide range of carbon sources provided that lactate formation is avoided. nevertheless, a low lactate flux is initiated as the growth rate declined in the transition to the stationary phase, which coincides with a drastic decrease in the glucose consumption and acetate production fluxes. in addition, the decrease in growth rate was accompanied by a sudden increase and then decrease in nadh levels. the v'(max) of the lactate d ... | 2010 | 20060925 |
| hydrolytic properties of a thermostable α-l-arabinofuranosidase from caldicellulosiruptor saccharolyticus. | to characterize of a thermostable recombinant α-l-arabinofuranosidase from caldicellulosiruptor saccharolyticus for the hydrolysis of arabino-oligosaccharides to l-arabinose. | 2010 | 20477891 |
| pyrophosphate as a central energy carrier in the hydrogen-producing extremely thermophilic caldicellulosiruptor saccharolyticus. | the role of inorganic pyrophosphate (ppi) as an energy carrier in the central metabolism of the extremely thermophilic bacterium caldicellulosiruptor saccharolyticus was investigated. in agreement with its annotated genome sequence, cell extracts were shown to exhibit ppi-dependent phosphofructokinase and pyruvate phosphate dikinase activity. in addition, membrane-bound pyrophosphatase activity was demonstrated, while no significant cytosolic pyrophosphatase activity was detected. during the exp ... | 2010 | 20557574 |
| characterization of a heat resistant beta-glucosidase as a new reporter in cells and mice. | reporter genes are widely used in biology and only a limited number are available. we present a new reporter gene for the localization of mammalian cells and transgenic tissues based on detection of the bgla (synbgla) gene of caldocellum saccharolyticum that encodes a thermophilic beta-glucosidase. | 2010 | 20569471 |
| part ii: defining and quantifying individual and co-cultured intracellular proteomes of two thermophilic microorganisms by gelc-ms2 and spectral counting. | probing the intracellular proteome of thermotoga maritima and caldicellulosiruptor saccharolyticus in pure and co-culture affords a global investigation into the machinery and mechanisms enduring inside the bacterial thermophilic cell at the time of harvest. the second of a two part study, employing gelc-ms(2) a variety of proteins were confidently identified with <1% false discovery rate, and spectral counts for label-free relative quantification afforded indication of the dynamic proteome as a ... | 2010 | 20582400 |
| part i: characterization of the extracellular proteome of the extreme thermophile caldicellulosiruptor saccharolyticus by gelc-ms2. | the proteome of extremely thermophilic microorganisms affords a glimpse into the dynamics of microbial ecology of high temperature environments. the secretome, or extracellular proteome of these microorganisms, no doubt harbors technologically important enzymes and other thermostable biomolecules that, to date, have been characterized only to a limited extent. in the first of a two-part study on selected thermophiles, defining the secretome requires a sample preparation method that has no negati ... | 2010 | 20623222 |
| hydrogen production by hyperthermophilic and extremely thermophilic bacteria and archaea: mechanisms for reductant disposal. | hydrogen produced from biomass by bacteria and archaea is an attractive renewable energy source. however, to make its application more feasible, microorganisms are needed with high hydrogen productivities. for several reasons, hyperthermophilic and extremely thermophilic bacteria and archaea are promising is this respect. in addition to the high polysaccharide-hydrolysing capacities of many of these organisms, an important advantage is their ability to use most of the reducing equivalents (e.g. ... | 2010 | 20662387 |
| exploitation of the extremely thermophilic caldicellulosiruptor saccharolyticus in hydrogen and biogas production from biomasses. | caldicellulosiruptor saccharolyticus has attracted considerable attention by virtue of its ability to degrade various polysaccharide, oligosaccharide and monosaccharide substrates at temperatures above 70 degrees c, while its ability to convert various sugars to hydrogen has led to c. saccharolyticus being selected for the fermentative production of hydrogen. in this study, the utilization of a pure cellulosic substrate and mixed biomasses of plant origin was investigated. cellulase biosynthesis ... | 2010 | 20662389 |
| complete genome sequence of the cellulolytic thermophile caldicellulosiruptor obsidiansis ob47t. | caldicellulosiruptor obsidiansis ob47(t) (atcc baa-2073, jcm 16842) is an extremely thermophilic, anaerobic bacterium capable of hydrolyzing plant-derived polymers through the expression of multidomain/multifunctional hydrolases. the complete genome sequence reveals a diverse set of carbohydrate-active enzymes and provides further insight into lignocellulosic biomass hydrolysis at high temperatures. | 2010 | 20851897 |
| phylogenetic, microbiological, and glycoside hydrolase diversities within the extremely thermophilic, plant biomass-degrading genus caldicellulosiruptor. | phylogenetic, microbiological, and comparative genomic analyses were used to examine the diversity among members of the genus caldicellulosiruptor, with an eye toward the capacity of these extremely thermophilic bacteria to degrade the complex carbohydrate content of plant biomass. seven species from this genus (c. saccharolyticus, c. bescii, c. hydrothermalis, c. owensensis, c. kronotskyensis, c. lactoaceticus, and c. kristjanssonii) were compared on the basis of 16s rrna gene phylogeny and cro ... | 2010 | 20971878 |
| reduction of galactose inhibition via the mutation of β-galactosidase from caldicellulosiruptor saccharolyticus for lactose hydrolysis. | for the removal of galactose inhibition, the predicted galactose binding residues, which were determined by sequence alignment, were replaced separately with ala. the activities of the ala-substituted mutant enzymes were assessed with the addition of galactose. as a consequence, amino acid at position 349 was correlated with the reduction in galactose inhibition. the f349s mutant exhibited the highest activity in the presence of galactose relative to the activity measured in the absence of galac ... | 2010 | 20972818 |
| mathematical modeling of hydrolysate diffusion and utilization in cellulolytic biofilms of the extreme thermophile caldicellulosiruptor obsidiansis. | in this study, a hydrolysate diffusion and utilization model was developed to examine factors influencing cellulolytic biofilm morphology. model simulations using caldicellulosiruptor obsidiansis revealed that the cellulolytic biofilm needs to generate more hydrolysate than it consumes to establish a higher than bulk solution intra-biofilm substrate concentration to support its growth. this produces a hydrolysate surplus that diffuses through the thin biofilm structure into the bulk solution, wh ... | 2010 | 21075617 |
| physiological characteristics of the extreme thermophile caldicellulosiruptor saccharolyticus: an efficient hydrogen cell factory. | global concerns about climate changes and their association with the use of fossil fuels have accelerated research on biological fuel production. biological hydrogen production from hemicellulose-containing waste is considered one of the promising avenues. a major economical issue for such a process, however, is the low substrate conversion efficiency. interestingly, the extreme thermophilic bacterium caldicellulosiruptor saccharolyticus can produce hydrogen from carbohydrate-rich substrates at ... | 2010 | 21092203 |
| probing the redox metabolism in the strictly anaerobic, extremely thermophilic, hydrogen-producing caldicellulosiruptor saccharolyticus using amperometry. | changes in the redox metabolism in the anaerobic, extremely thermophilic, hydrogen-forming bacterium caldicellulosiruptor saccharolyticus were probed for the first time in vivo using mediated amperometry with ferricyanide as a thermotolerant external mediator. clear differences in the intracellular electron flow were observed when cells were supplied with different carbon sources. a higher electrochemical response was detected when cells were supplied with xylose than with sucrose or glucose. mo ... | 2010 | 21132340 |
| stable coexistence of two caldicellulosiruptor species in a de novo constructed hydrogen-producing co-culture. | mixed culture enrichments have been used frequently for biohydrogen production from different feedstock. in spite of the several advantages offered by those cultures, they suffer poor h2 yield. constructing defined co-cultures of known h2 producers may offer a better performance than mixed-population enrichments, while overcoming some of the limitations of pure cultures based on synergies among the microorganisms involved. | 2010 | 21192828 |
| synergistic production of l-arabinose from arabinan by the combined use of thermostable endo- and exo-arabinanases from caldicellulosiruptor saccharolyticus. | the optimum conditions for the production of l-arabinose from debranched arabinan were determined to be ph 6.5, 75°c, 20 g l(-1) debranched arabinan, 42 um l(-1) endo-1,5-α-l-arabinanase, and 14 u ml(-1) α-l-arabinofuranosidase from caldicellulosiruptor saccharolyticus and the conditions for sugar beet arabinan were ph 6.0, 75°c, 20 g l(-1) sugar beet arabinan, 3 u ml(-1) endo-1,5-α-l-arabinanase, and 24 u ml(-1) α-l-arabinofuranosidase. under the optimum conditions, 16 g l(-1)l-arabinose was ob ... | 2010 | 21216591 |
| complete genome sequences for the anaerobic, extremely thermophilic plant biomass-degrading bacteria caldicellulosiruptor hydrothermalis, caldicellulosiruptor kristjanssonii, caldicellulosiruptor kronotskyensis, caldicellulosiruptor owensensis, and caldicellulosiruptor lactoaceticus. | the genus caldicellulosiruptor contains the most thermophilic, plant biomass-degrading bacteria isolated to date. previously, genome sequences from three cellulolytic members of this genus were reported (c. saccharolyticus, c. bescii, and c. obsidiansis). to further explore the physiological and biochemical basis for polysaccharide degradation within this genus, five additional genomes were sequenced: c. hydrothermalis, c. kristjanssonii, c. kronotskyensis, c. lactoaceticus, and c. owensensis. t ... | 2011 | 21216991 |
| insights into plant biomass conversion from the genome of the anaerobic thermophilic bacterium caldicellulosiruptor bescii dsm 6725. | caldicellulosiruptor bescii dsm 6725 utilizes various polysaccharides and grows efficiently on untreated high-lignin grasses and hardwood at an optimum temperature of ∼ 80 °c. it is a promising anaerobic bacterium for studying high-temperature biomass conversion. its genome contains 2666 protein-coding sequences organized into 1209 operons. expression of 2196 genes (83%) was confirmed experimentally. at least 322 genes appear to have been obtained by lateral gene transfer (lgt). putative functio ... | 2011 | 21227922 |
| chemoenzymatic synthesis of diverse thiohydroximates from glucosinolate-utilizing enzymes from helix pomatia and caldicellulosiruptor saccharolyticus. | thiohydroximates comprise a diverse class of compounds important in both biological and industrial chemistry. their syntheses are generally limited to simple alkyl and aryl compounds with few stereocenters and a narrow range of functional groups. we hypothesized that sequential action of two recombinant enzymes, a sulfatase from helix pomatia and a ß-o-glucosidase from caldicellulosiruptor saccharolyticus, on glucosinolates would allow synthesis of thiohydroximates from a structurally broad arra ... | 2011 | 21267762 |
| glycoside hydrolase inventory drives plant polysaccharide deconstruction by the extremely thermophilic bacterium caldicellulosiruptor saccharolyticus. | the genome of caldicellulosiruptor saccharolyticus encodes a range of glycoside hydrolases (ghs) that mediate plant biomass deconstruction by this bacterium. two gh-based genomic loci that appear to be central to the hydrolysis of hemicellulosic and cellulosic substrates were examined. xynb-xynf (csac_2404-csac_2411) encodes intracellular and extracellular ghs that are active towards xylan and xylan side-chains, as well as carboxymethyl cellulose (cmc). xynd (csac_2409) and xyne (csac_2410) were ... | 2011 | 21337327 |
| enzymatic hydrolysis of cellulose by the cellobiohydrolase domain of celb from the hyperthermophilic bacterium caldicellulosiruptor saccharolyticus. | the celb gene of caldicellulosiruptor saccharolyticus was cloned and expressed in escherichia coli to create a recombinant biocatalyst for hydrolyzing lignocellulosic biomass at high temperature. the gh5 domain of celb hydrolyzed 4-nitrophenyl-β-d-cellobioside and carboxymethyl cellulose with optimum activity at ph 4.7-5.5 and 80°c. the recombinant gh5 and cbm3-gh5 constructs were both stable at 80°c with half-lives of 23 h and 39 h, respectively, and retained >94% activity after 48 h at 70°c. e ... | 2011 | 21421309 |
| label-free quantitative proteomics distinguish the secreted cellulolytic systems of caldicellulosiruptor bescii and caldicellulosiruptor obsidiansis. | the extremely thermophilic gram-positive bacteria caldicellulosiruptor bescii and caldicellulosiruptor obsidiansis efficiently degrade both cellulose and hemicellulose, making them relevant models for lignocellulosic biomass deconstruction to produce sustainable biofuels. to identify the shared and unique features of secreted cellulolytic apparatuses from c. bescii and c. obsidiansis, label-free quantitative proteomics was used to analyze protein abundance over the course of fermentative growth ... | 2011 | 21498747 |
| identification and characterization of cbei, a novel thermostable restriction enzyme from caldicellulosiruptor bescii dsm 6725 and a member of a new subfamily of haeiii-like enzymes. | potent haeiii-like dna restriction activity was detected in cell-free extracts of caldicellulosiruptor bescii dsm 6725 using plasmid dna isolated from escherichia coli as substrate. incubation of the plasmid dna in vitro with haeiii methyltransferase protected it from cleavage by haeiii nuclease as well as cell-free extracts of c. bescii. the gene encoding the putative restriction enzyme was cloned and expressed in e. coli with a his-tag at the c-terminus. the purified protein was 38 kda as pred ... | 2011 | 21604181 |
| enzymatic properties of recombinant kojibiose phosphorylase from caldicellulosiruptor saccharolyticus atcc43494. | one kojibiose phoshorylase (kp) homolog gene was cloned from caldicellulosiruptor saccharolyticus atcc43494. recombinant kp from c. saccharolyticus (cs-kp) expressed in escherichia coli showed highest activity at ph 6.0 at 85 ┬░c, and was stable from ph 3.5 to 10.0 and up to 85 ┬░c for phosphorolysis. cs-kp showed higher productivity of kojioligosaccharides of dp ôëº 4 than kp from thermoanaerobacter brockii atcc35047. | 2011 | 21670511 |
| characterization of a thermophilic l-rhamnose isomerase from caldicellulosiruptor saccharolyticus atcc 43494. | l-rhamnose isomerase (ec 5.3.1.14, l-rhi) catalyzes the reversible aldose-ketose isomerization between l-rhamnose and l-rhamnulose. in this study, the l-rhi gene encoding l-rhi was pcr-cloned from caldicellulosiruptor saccharolyticus atcc 43494 and then expressed in escherichia coli . a high yield of active l-rhi, 3010 u/g of wet cells, was obtained after 20 °c induction for 20 h. the enzyme was purified sequentially using heat treatment, nucleic acid precipitation, and ion-exchange chromatograp ... | 2011 | 21761877 |
| characterization of a recombinant cellobiose 2-epimerase from caldicellulosiruptor saccharolyticus and its application in the production of mannose from glucose. | a putative n-acyl-d: -glucosamine 2-epimerase from caldicellulosiruptor saccharolyticus was cloned and expressed in escherichia coli. the recombinant enzyme was identified as a cellobiose 2-epimerase by the analysis of the activity for substrates, acid-hydrolyzed products, and amino acid sequence. the cellobiose 2-epimerase was purified with a specific activity of 35-ánmol-ámin(-1)-ámg(-1) for d: -glucose with a 47-kda monomer. the epimerization activity for d: -glucose was maximal at ph-á7.5 an ... | 2011 | 21691788 |
| reassessment of hydrogen tolerance in caldicellulosiruptor saccharolyticus. | abstract: background: caldicellulosiruptor saccharolyticus has the ability to produce hydrogen (h2) at high yields from a wide spectrum of carbon sources, and has therefore gained industrial interest. for a cost-effective biohydrogen process, the ability of an organism to tolerate high partial pressures of h2 (ph2) is a critical aspect to eliminate the need for continuous stripping of the produced h2 from the bioreactor. results: herein, we demonstrate that, under given conditions, growth and ... | 2011 | 22189215 |
| fSpatial and temporal dynamics of cellulose degradation and biofilm formation by Caldicellulosiruptor obsidiansis and Clostridium thermocellum. | ABSTRACT: Cellulose degradation is one of the major bottlenecks of a consolidated bioprocess that employs cellulolytic bacterial cells as catalysts to produce biofuels from cellulosic biomass. In this study, we investigated the spatial and temporal dynamics of cellulose degradation by Caldicellulosiruptfor obsidiansis, which does not produce cellulosomes, and Clostridium thermocellum, which does produce cellulosomes. Results showed that the degradation of either regenerated or natural cellulose ... | 2011 | 21982458 |
| S-layer homology (SLH) domain proteins Csac_0678 and Csac_2722 implicated in plant polysaccharide deconstruction by the extremely thermophilic bacterium Caldicellulosiruptor saccharolyticus. | The genus Caldicellulosiruptor contains extremely thermophilic bacteria that grow on plant polysaccharides. The genomes of Caldicellulosiruptor species reveal certain surface layer homology (SLH) domain proteins that have distinguishing features, pointing to a role in lignocellulose deconstruction. Two of these proteins in Caldicellulosiruptor saccharolyticus (Csac_0678 and Csac_2722) were examined from this perspective. In addition to three contiguous SLH domains, Csac_0678 encodes a glycoside ... | 2011 | 22138994 |
| Lactulose production from lactose as a single substrate by a thermostable cellobiose 2-epimerase from Caldicellulosiruptor saccharolyticus. | The conditions for maximum lactulose production from lactose, as a single substrate, by a thermostable recombinant cellobiose-2-epimerase from Caldicellulosiruptor saccharolyticus were determined to be pH 7.5, 80°C, 700gl(-1) lactose, and 150Uml(-1) of enzyme. Under the conditions, the enzyme produced the two bifidus factors lactulose at 408gl(-1) and epilactose at 107gl(-1) after 2h. The yields of lactulose and epilactose from lactose and the productivities of lactulose and epilactose were 58%, ... | 2012 | 22123300 |
| A kinetic model for quantitative evaluation of the effect of hydrogen and osmolarity on hydrogen production by Caldicellulosiruptor saccharolyticus. | ABSTRACT: | 2011 | 21914204 |
| l-Arabinose production from sugar beet arabinan by immobilized endo- and exo-arabinanases from Caldicellulosiruptor saccharolyticus in a packed-bed reactor. | The immobilized endo- and exo-arabinanases from Caldicellulosiruptor saccharolyticus produced continuously an average of 16.5gl(-1)l-arabinose from 20gl(-1) sugar beet arabinan at pH 5.0 and 75°C for 216h, with a productivity of 9.9gl(-1)h(-1) and a conversion yield of 83%. | 2011 | 22099373 |
| label-free quantitative proteomics for the extremely thermophilic bacterium caldicellulosiruptor obsidiansis reveal distinct abundance patterns upon growth on cellobiose, crystalline cellulose, and switchgrass. | mass spectrometric analysis of caldicellulosiruptor obsidiansis cultures grown on four different carbon sources identified 65% of the cells' predicted proteins in cell lysates and supernatants. biological and technical replication together with sophisticated statistical analysis were used to reliably quantify protein abundances and their changes as a function of carbon source. extracellular, multifunctional glycosidases were significantly more abundant on cellobiose than on the crystalline cellu ... | 2011 | 21988591 |
| a 1.5 å resolution x-ray structure of the catalytic module of caldicellulosiruptor bescii family 3 pectate lyase. | a 1.5 å resolution x-ray structure of the catalytic module of caldicellulosiruptor bescii family 3 pectate lyase is reported (pdb entry 3t9g). the resulting structure was refined to an r factor of 0.143 and an r(free) of 0.178. structural analysis shows that this new structure is very similar to the previously solved structure of a family 3 pectate lyase from bacillus sp. strain ksm-p15 (pdb entry 1ee6), with a root-mean-square deviation of 0.93 å and a sequence identity of 53%. this structural ... | 2011 | 22139151 |
| biochemical and mutational analyses of a multi-domain cellulase/mannanase from caldicellulosiruptor bescii. | thermophilic cellulases and hemicellulases are of significant interest to the biofuel industry due to their perceived advantages over their mesophilic counterparts. we report the biochemical and mutational analyses of caldicellulosiruptor bescii cel9b/man5a (cbcel9b/man5a), a highly thermophilic enzyme. as one of the highly secreted proteins of c. bescii, the enzyme is likely to be critical to nutrient acquisition by the bacterium. cbcel9b/man5a is a modular protein composed of three carbohydrat ... | 2012 | 22247178 |