| homologous catalytic domains in a rumen fungal xylanase: evidence for gene duplication and prokaryotic origin. | a cdna (xyna), encoding xylanase a (xyla), was isolated from a cdna library, derived from mrna extracted from the rumen anaerobic fungus, neocallimastix patriciarum. recombinant xyla, purified from escherichia coli harbouring xyna, had a m(r) of 53,000 and hydrolysed oat-spelt xylan to xylobiose and xylose. the enzyme did not hydrolyse any cellulosic substrates. the nucleotide sequence of xyna revealed a single open reading frame of 1821 bp coding for a protein of m(r) 66,192. the predicted prim ... | 1992 | 1406248 |
| cloning and expression of multiple cellulase cdnas from the anaerobic rumen fungus neocallimastix patriciarum in escherichia coli. | a cdna expression library of the rumen fungus neocallimastix patriciarum was made in escherichia coli. cellulolytic clones were identified by screening on a medium containing carboxymethylcellulose. restriction mapping and southern hybridization analysis of selected clones revealed three distinct cellulase cdnas, designated cela, celb and celc. studies on the substrate specificity showed that the enzyme encoded by cela had high activity towards amorphous and microcrystalline cellulose, while the ... | 1992 | 1512573 |
| effect of condensed tannins from birdsfoot trefoil on endoglucanase activity and the digestion of cellulose filter paper by ruminal fungi. | the ruminal fungi neocallimastix frontalis re1, neocallimastix patriciarum 27, piromyces communis 22, and orpinomyces joyonii 19-2 were examined for their ability to digest filter paper in the presence of condensed tannins from birdsfoot trefoil (lotus corniculatus l.). for all four fungi, inhibition of endoglucanases was evident at 100 micrograms condensed tannins.ml-1 with nearly complete inhibition at 300 micrograms condensed tannins.ml-1. at 100 and 200 micrograms condensed tannins.ml-1, the ... | 1994 | 8039053 |
| solubilization of lignin by the ruminal anaerobic fungus neocallimastix patriciarum. | the ability of the ruminal anaerobic phycomycete neocallimastix patriciarum to digest model lignin compounds and lignified structures in plant material was studied in batch culture. the fungus did not degrade or transform model lignin compounds that were representative of the predominant intermonomer linkages in lignin, nor did it solubilize acid detergent lignin that had been isolated from spear grass. in a stem fraction of sorghum, 33.6% of lignin was apparently solubilized by the fungus. solu ... | 1994 | 8085834 |
| the xync gene from fibrobacter succinogenes s85 codes for a xylanase with two similar catalytic domains. | the xync gene of fibrobacter succinogenes s85 codes for a 66.4-kda xylanase which consists of three distinct domains separated by two flexible regions rich in serine residues. domains a and b of xync code for catalytic domains with 56.5% identity and 9.6% similarity with each other, and both domains share homology with xylanases of ruminococcus flavefaciens, neocallimastix patriciarum, clostridium acetobutylicum, bacillus pumilus, bacillus subtilis, and bacillus circulans. more than 88% of the x ... | 1993 | 8244936 |
| expression of a modified neocallimastix patriciarum xylanase in butyrivibrio fibrisolvens digests more fibre but cannot effectively compete with highly fibrolytic bacteria in the rumen. | this study investigated the competitive abilities of two neocallimastix patriciarum-derived xylanases constructs in butyrivibrio fibrisolvens h17c (xyna and pumsx) and their ability to compete in vivo. | 2001 | 11298234 |
| xylanase b from neocallimastix patriciarum contains a non-catalytic 455-residue linker sequence comprised of 57 repeats of an octapeptide. | a neocallimastix patriciarum cdna library was screened for xylanase-expressing clones, which were distinct from the previously characterized n. patriciarum xyna cdna encoding xylanase a. a single cdna, designated xynb, which did not exhibit homology with xyna, was isolated. northern-blot analysis of mrna from avicel-grown n. patriciarum showed that xynb hybridized to a 3.4 kb mrna species. the nucleotide sequence of xynb revealed a single open reading frame of 2580 bp coding for a protein design ... | 1994 | 8172598 |
| modification of a xylanase cdna isolated from an anaerobic fungus neocallimastix patriciarum for high-level expression in escherichia coli. | a neocallimastix patriciarum xylanase cdna with the core coding sequence essentially identical to xyna was isolated and modified for high-level expression in escherichia coli. the xylanase cdna was truncated into individual catalytic domains, which were modified at the n-terminus. these modified xylanases were synthesised as non-fusion proteins under the control of the tac promoter. high-level expression was obtained with the modified domain ii construct, accounting for approx. 25% of total cell ... | 1995 | 7765876 |
| transformation and expression of an anaerobic fungal xylanase in several strains of the rumen bacterium butyrivibrio fibrisolvens. | to obtain reliable transformation of a range of butyrivibrio fibrisolvens strains and to express a neocallimastix patriciarum xylanase gene in the recipients. | 2002 | 12067381 |
| interactions between rumen anaerobic fungi and ciliate protozoa in the degradation of rice straw cell walls. | suspensions of mixed rumen protozoa were added to incubations of the anaerobic fungus neocallimastix patriciarum with rice straw cell walls. the protozoa did not influence the dry matter lost from the straw, or the solubilization of monosaccharides, but they had a marked effect on the fermentation products formed. studies with 14c-labelled protozoa suggested that the presence of protozoa reduced the fungal carboxymethylcellulase activity to around half of that found in pure cultures of the fungu ... | 1995 | 7765871 |
| comparison of amylolytic and proteolytic activities of ruminal fungi grown on cereal grains. | strains of the ruminal fungi neocallimastix patriciarum, orpinomyces joyonii, and piromyces communis were grown on cellobiose and on cereal grains and then examined for proteolytic and amylolytic activities. on cellobiose all three fungi displayed similar activities, with the exception of little amylolytic activity in the cell-associated fraction of n. patriciarum. growth on the cereal grains barley, corn, and wheat showed differences in proteolytic and amylolytic activities amongst the ruminal ... | 1993 | 7693316 |
| alpha-(4-o-methyl)-d-glucuronidase activity produced by the rumen anaerobic fungus piromonas communis: a study of selected properties. | the rumen anaerobic fungus piromonas communis, unlike the rumen anaerobic fungi neocallimastix frontalis and neocallimastix patriciarum, produced extracellular alpha-(4-o-methyl)-d-glucuronidase when grown in cultures containing filter-paper, barley straw, birchwood xylan or birchwood sawdust as carbon source. the highest concentration of enzyme was produced in cultures containing birchwood sawdust. the aldobiouronic acid o-alpha-(4-o-methyl-d-glucopyranosyluronic acid)-(1-->2)-d-xylopyranose (m ... | 1995 | 7576556 |
| glycoside hydrolase enzymes present in the zoospore and vegetative growth stages of the rumen fungi neocallimastix patriciarum, piromonas communis, and an unidentified isolate, grown on a range of carbohydrates. | the rumen fungi neocallimastix patriciarum, piromonas communis, and a morphologically distinct but unidentified isolate were cultivated on the polysaccharides starch, cellulose, xylan, and their principal component monosaccharides and disaccharides, and the range and specific activities of the glycoside hydrolases formed were monitored using gluco-oligosaccharide and p-nitrophenyl glycoside substrates. a wide range of enzyme activities was detected in preparations from vegetative growth and zoos ... | 1987 | 3607611 |
| polysaccharide-degrading enzymes formed by three species of anaerobic rumen fungi grown on a range of carbohydrate substrates. | the range of polysaccharide-degrading enzymes formed by three anaerobic rumen fungi (neocallimastix patriciarum, piromonas communis, and an unidentified isolate (f] was monitored following growth on seven mono-, di-, and poly-saccharide carbohydrate substrates. enzymes capable of degrading a variety of alpha- and beta-glucans, beta-galactans, galactomannan, and hemicellulosic arabinoxylans were present in all three isolates. although reducing saccharides were released from pectin, polygalacturon ... | 1987 | 3607610 |
| hydrogenosomes in the rumen fungus neocallimastix patriciarum. | sedimentable hydrogenase activity was demonstrated in cell-free extracts from both zoospores and vegetative growth of the anaerobic rumen fungus neocallimastix patriciarum. electron micrographs of the fraction enriched in hydrogenase activity contained finely granular microbody-like organelles, about 0.5 micron in diameter and having an equilibrium density of about 1.2 g x ml-1 in sucrose, 1.12 g x ml-1 in percoll and 1.27-1.28 g x ml-1 in metrizamide. these organelles, which are sedimentable at ... | 1986 | 3539104 |
| a novel polysaccharide hydrolase cdna (celd) from neocallimastix patriciarum encoding three multi-functional catalytic domains with high endoglucanase, cellobiohydrolase and xylanase activities. | a plant polysaccharide hydrolase cdna, designated celd, was isolated from a cdna library of the rumen fungus neocallimastix patriciarum. the enzyme encoded by celd had endoglucanase, cellobiohydrolase and xylanase activities. deletion analysis revealed that celd cdna can be truncated to code for three catalytically active domains. each domain had the same substrate specificity as the enzyme produced by the untruncated celd and also possessed cellulose-binding capacity. substrate competition stud ... | 1992 | 1479358 |
| stable linker peptides for a cellulose-binding domain-lipase fusion protein expressed in pichia pastoris. | fusion proteins composed of a cellulose-binding domain from neocallimastix patriciarum cellulase a and candida antarctica lipase b were constructed using different linker peptides. the aim was to create proteolytically stable linkers that were able to join the functional modules without disrupting their function. six fusion variants containing linkers of 4-44 residues were expressed in pichia pastoris and analysed. three variants were found to be stable throughout 7-day cultivations. the cellulo ... | 2001 | 11707619 |
| clostridium beijerinckii cells expressing neocallimastix patriciarum glycoside hydrolases show enhanced lichenan utilization and solvent production. | growth and the production of acetone, butanol, and ethanol by clostridium beijerinckii ncimb 8052 on several polysaccharides and sugars were analyzed. on crystalline cellulose, growth and solvent production were observed only when a mixture of fungal cellulases was added to the medium. on lichenan growth and solvent production occurred, but this polymer was only partially utilized. to increase utilization of these polymers and subsequent solvent production, the genes for two new glycoside hydrol ... | 2001 | 11679336 |
| expression in pichia pastoris of candida antarctica lipase b and lipase b fused to a cellulose-binding domain. | candida antarctica lipase b (calb) and c. antarctica lipase b fused to a cellulose-binding domain (cbd-calb) were expressed functionally in the methylotrophic yeast pichia pastoris. the cellulose-binding domain originates from cellulase a of the anaerobic rumen fungus neocallimastix patriciarum. the genes were fused to the alpha-factor secretion signal sequence of saccharomyces cerevisiae and placed under the control of the alcohol oxidase gene (aox1) promoter. the recombinant proteins were secr ... | 2001 | 11281712 |
| a comparison of enzyme-aided bleaching of softwood paper pulp using combinations of xylanase, mannanase and alpha-galactosidase. | enzymatic pretreatment of softwood kraft pulp was investigated using xylanase a (xyla) from neocallimastix patriciarum in combination with mannanase and alpha-galactosidase. mannanase a (mana) from pseudomonas fluorescens subsp. cellulosa and mana from clostridium thermocellum, both family 26 glycosyl hydrolases, are structurally diverse and exhibit different ph and temperature optima. although neither mannanase was effective in pretreating softwood pulp alone, both enzymes were able to enhance ... | 2000 | 10919323 |
| characterization of a neocallimastix patriciarum xylanase gene and its product. | a xylanase gene (xync) isolated from the anaerobic ruminal fungus neocallimastix patriciarum was characterized. the gene consists of an n-terminal catalytic domain that exhibited homology to family 11 of glycosyl hydrolases, a c-terminal cellulose binding domain (cbd) and a putative dockerin domain in between. each domain was linked by a short linker domain rich in proline and alanine. deletion analysis demonstrated that the cbd was essential for optimal xylanase activity of the enzyme, while th ... | 1999 | 10588045 |
| an acetylxylan esterase and a xylanase expressed from genes cloned from the ruminal fungus neocallimastix patriciarum act synergistically to degrade acetylated xylans. | a neocallimastit patriciarum acetylxylan esterase (bnaa) was expressed from the cloned gene in escherichia coli. purified recombinant bnaa efficiently released acetate from soluble acetylated birchwood xylan (abx), with a specific activity of 76 u mg-1. in contrast, release of acetate was very inefficient from the insoluble substrates, spear grass and delignified spear grass. addition of a recombinant xylanase, xyna, also expressed from a cloned n. patriciarum gene, had no effect on the release ... | 1999 | 10499262 |
| characterization of an acetyl xylan esterase from the anaerobic fungus orpinomyces sp. strain pc-2. | a 1,067-bp cdna, designated axea, coding for an acetyl xylan esterase (axea) was cloned from the anaerobic rumen fungus orpinomyces sp. strain pc-2. the gene had an open reading frame of 939 bp encoding a polypeptide of 313 amino acid residues with a calculated mass of 34,845 da. an active esterase using the original start codon of the cdna was synthesized in escherichia coli. two active forms of the esterase were purified from recombinant e. coli cultures. the size difference of 8 amino acids w ... | 1999 | 10473406 |
| immobilization of neocallimastix patriciarum xylanase on artificial oil bodies and statistical optimization of enzyme activity. | a thermally stable and alkalophilic xylanase, xyncdbfv, from neocallimastix patriciarum was overexpressed in escherichia coli as a recombinant protein fused to the n-terminus of oleosin, a unique structural protein of seed oil bodies. as a result of the reconstitution of the artificial oil bodies (aobs), the immobilization of active xylanase was accomplished. response surface methodology (rsm) was employed for the optimization of the immobilized xylanase activity. the central composite design (c ... | 2008 | 18495476 |
| three neocallimastix patriciarum esterases associated with the degradation of complex polysaccharides are members of a new family of hydrolases. | acetylesterase and cinnamoyl ester hydrolase activities were demonstrated in culture supernatant of the anaerobic ruminal fungus neocallimastix patriciarum. a cdna expression library from n. patriciarum was screened for esterases using beta-naphthyl acetate and a model cinnamoyl ester compound. cdna clones representing four different esterase genes (bnaa-d) were isolated. none of the enzymes had cinnamoyl ester hydrolase activity, but two of the enzymes (bnaa and bnac) had acetylxylan esterase a ... | 1997 | 9274014 |
| improvement of expression and secretion of a fungal xylanase in the rumen bacterium butyrivibrio fibrisolvens ob156 by manipulation of promoter and signal sequences. | promoters and signal sequences for expression and secretion of a fungal xylanase encoded by a modified neocallimastix patriciarum xyna cdna in the rumen bacterium, butyrivibrio fibrisolvens ob156, were investigated. successful expression of the fungal xylanase in ob156 was obtained using the putative xylanase promoter from b. fibrisolvens strain 49. replacing the putative -35 region sequence (ttgcac) of the xylanase promoter with the sequence ttgaca by mutagenesis reduced the fungal xylanase exp ... | 1997 | 9195758 |
| monocentric and polycentric anaerobic fungi produce structurally related cellulases and xylanases. | cellulase and xylanase cdnas were isolated from a cdna library of the polycentric anaerobic fungus orpinomyces sp. strain pc-2 constructed in escherichia coli. the cellulase cdna (celb) was 1.8 kb long with an open reading frame (orf) coding for a polypeptide of 471 amino acids, and the xylanase cdna (xyna) was 1.2 kb long with an orf encoding a polypeptide of 362 amino acids. single transcripts of 1.9 kb for celb and 1.5 kb for xyna were detected in total rna of orpinomyces grown on avicel. gen ... | 1997 | 9023940 |
| characterization of a neocallimastix patriciarum cellulase cdna (cela) homologous to trichoderma reesei cellobiohydrolase ii. | the nucleotide sequence of a cellulase cdna (cela) from the rumen fungus neocallimastix patriciarum and the primary structure of the protein which it encodes were characterized. the cela cdna was 1.95 kb long and had an open reading frame of 1,284 bp, which encoded a polypeptide having 428 amino acid residues. a sequence alignment showed that cellulase a (cela) exhibited substantial homology with family b cellulases (family 6 glycosyl hydrolases), particularly cellobiohydrolase ii from the aerob ... | 1996 | 8787388 |
| the effects of co-cultivation with the acetogen acetitomaculum ruminis on the fermentative metabolism of the rumen fungi neocallimastix patriciarum and neocallimastix sp. strain l2. | the effects of co-cultivation with the hydrogen-utilizing acetogenic bacterium acetitomaculum ruminis on the fermentative activities of the rumen fungi neocallimastix patriciarum or neocallimastix sp. l2 were investigated. in both co-cultures acetate production increased, making it the predominant fermentation product, as the accumulation of lactate, formate, ethanol, h2 and (in the case of neocallimastix sp. l2) succinate all decreased. the effects of co-cultivation with methanobrevibacter smit ... | 1995 | 8566705 |
| cereal grain digestion by selected strains of ruminal fungi. | the ruminal fungi orpinomyces joyonii strain 19-2, neocallimastix patriciarum strain 27, and piromyces communis strain 22 were examined for their ability to digest cereal starch. all strains digested corn starch more readily than barley or wheat starch. orpinomyces joyonii 19-2 exhibited the greatest propensity to digest starch in wheat and barley, whereas the digestion of these starches by n. patriciarum 27 and p. communis 22 was limited. media ammonia concentrations were lower when fungal grow ... | 1993 | 8500008 |
| cloning of a xylanase gene from the ruminal fungus neocallimastix patriciarum 27 and its expression in escherichia coli. | an endo-beta-1,4-xylanase gene was cloned from neocallimastix patriciarum 27 in the bacteriophage vector lambda gtwes lambda b and was subcloned into the plasmid vectors puc18 and puc19 in which xylanase activity was expressed in both orientations. the xylanase was located in the periplasmic space of the host, escherichia coli hb101. the ph and temperature optima for periplasmic xylanase activity were 6.2 and 40 degrees c, respectively, and the km for oat spelt xylan hydrolysis was 0.89 mg.ml-1. ... | 1993 | 8439870 |
| intronless celb from the anaerobic fungus neocallimastix patriciarum encodes a modular family a endoglucanase. | the cdna designated celb from the anaerobic rumen fungus neocallimastix patriciarum contained a single open reading frame of 1422 bp coding for a protein (celb) of m(r) 53,070. celb expressed by escherichia coli harbouring the full-length gene hydrolysed carboxymethylcellulose in the manner of an endoglucanase, but was most active against barley beta-glucan. it also released reducing sugar from xylan and lichenan, but was inactive against crystalline cellulose, laminarin, mannan, galactan and ar ... | 1994 | 8297343 |
| directed evolution to produce an alkalophilic variant from a neocallimastix patriciarum xylanase. | the catalytic domain of a xylanase from the anaerobic fungus neocallimastix patriciarum was made more alkalophilic through directed evolution using error-prone pcr. transformants expressing the alkalophilic variant xylanases produced larger clear zones when overlaid with high ph, xylan-containing agar. eight amino acid substitutions were identified in six selected mutant xylanases. whereas the wild-type xylanase exhibited no activity at ph 8.5, the relative and specific activities of the six mut ... | 2001 | 11822834 |
| characterisation of the dna-binding profile of barley hvcbf1 using an enzymatic method for rapid, quantitative and high-throughput analysis of the dna-binding activity. | a rapid and quantitative dna-binding assay was developed based on the translational fusion of a dna-binding protein (dbp) with a neocallimastix patriciarum beta-1,4-d-glucanase, celd. celd releases a fluorescent 4-methylumbelliferyl product from 4-methylumbelliferyl cellobioside. this hydrolysis activity was used to quantify the amount of dbp-celd bound to an immobilised biotin-labelled target sequence. the dna-binding assay can be performed in a 96-well plate format for high- throughput analysi ... | 2002 | 12140339 |
| fungal hydrogenosomes contain mitochondrial heat-shock proteins. | at least three groups of anaerobic eukaryotes lack mitochondria and instead contain hydrogenosomes, peculiar organelles that make energy and excrete hydrogen. published data indicate that ciliate and trichomonad hydrogenosomes share common ancestry with mitochondria, but the evolutionary origins of fungal hydrogenosomes have been controversial. we have now isolated full-length genes for heat shock proteins 60 and 70 from the anaerobic fungus neocallimastix patriciarum, which phylogenetic analyse ... | 2003 | 12716992 |
| celf of orpinomyces pc-2 has an intron and encodes a cellulase (celf) containing a carbohydrate-binding module. | a cdna, designated celf, encoding a cellulase (celf) was isolated from the anaerobic fungus orpinomyces pc-2. the open reading frame contains regions coding for a signal peptide, a carbohydrate-binding module (cbm), a linker, and a catalytic domain. the catalytic domain was homologous to those of cela and celc of the same fungus and to that of the neocallimastix patriciarum cela, but celf lacks a docking domain, characteristic for enzymes of cellulosomes. it was also homologous to the cellobiohy ... | 2003 | 12721415 |
| the conserved noncatalytic 40-residue sequence in cellulases and hemicellulases from anaerobic fungi functions as a protein docking domain. | two cdnas, designated xyna and mana, encoding xylanase a (xyla) and mannanase a (mana), respectively, were isolated from a cdna library derived from mrna extracted from the anaerobic fungus, piromyces. xyla and mana displayed properties typical of endo-beta 1,4-xylanases and mannanases, respectively. neither enzyme hydrolyzed cellulosic substrates. the nucleotide sequences of xyna and mana revealed open reading frames of 1875 and 1818 base pairs, respectively, coding for proteins of m(r) 68,049 ... | 1995 | 7493964 |
| temperature limited fed-batch technique for control of proteolysis in pichia pastoris bioreactor cultures. | background: a temperature limited fed-batch (tlfb) technique is described and used for pichia pastoris mut+ strain cultures and compared with the traditional methanol limited fed-batch (mlfb) technique. a recombinant fusion protein composed of a cellulose-binding module (cbm) from neocallimastix patriciarum cellulase 6a and lipase b from candida antarctica (calb), was produced and secreted by this strain. results: a protein concentration of about 1 g l-1 was produced in the mlfb process. however ... | 2003 | 12871597 |
| hydrogenosomal succinyl-coa synthetase from the rumen-dwelling fungus neocallimastix patriciarum; an energy-producing enzyme of mitochondrial origin. | hydrogenosomes are hydrogen-producing organelles that are related to mitochondria and found in a variety of evolutionarily unrelated anaerobic microbial eukaryotes. similar to classic mitochondria, hydrogenosomes contain the enzyme catalyzing the only reaction of the citric acid cycle directly producing energy; succinyl-coa synthetase. we have isolated and characterized the genes encoding both subunits of this enzyme from the anaerobic chytrid fungus neocallimastix patriciarum, a model organism ... | 2006 | 16515848 |
| butyrivibrio spp. and other xylanolytic microorganisms from the rumen have cinnamoyl esterase activity. | high concentrations of hydroxycinnamic acids in the hemicellulosic fraction of dry season tropical grasses may influence the rate of microbial degradation of arabinoxylans by ruminant animals. the ability of 22 strains of butyrivibrio fibrisolvens, other ruminal bacteria (ruminococcus albus sy3, ruminococcus flavefaciens rf1,prevotella ruminicola ar20) and the ruminal phycomycete neocallimastix patriciarum cx to digest the tropical grass heteropogon contortus(spear grass) and hydrolyse esterifie ... | 1998 | 16887624 |
| incorporation of fungal cellulases in bacterial minicellulosomes yields viable, synergistically acting cellulolytic complexes. | artificial designer minicellulosomes comprise a chimeric scaffoldin that displays an optional cellulose-binding module (cbm) and bacterial cohesins from divergent species which bind strongly to enzymes engineered to bear complementary dockerins. incorporation of cellulosomal cellulases from clostridium cellulolyticum into minicellulosomes leads to artificial complexes with enhanced activity on crystalline cellulose, due to enzyme proximity and substrate targeting induced by the scaffoldin-borne ... | 2007 | 17468286 |
| coexpression of rumen microbial beta-glucanase and xylanase genes in lactobacillus reuteri. | the aim of this study was to clone and coexpress two rumen fibrolytic enzyme genes in lactobacillus reuteri. the ability of the genetically modified strain to degrade beta-glucan and xylan was evaluated. the fibrobacter succinogenes beta-glucanase (1,3-1,4-beta-d: -glucan 4-glucanohydrolase [ec 3.2.1.73]) gene and the neocallimastix patriciarum xylanase gene, xyncdbfv, were constructed to coexpress and secrete under control of the lactococcus lactis laca promoter and its secretion signal and the ... | 2007 | 17694302 |
| understanding the structural basis for substrate and inhibitor recognition in eukaryotic gh11 xylanases. | endo-beta1,4-xylanases (xylanases) hydrolyse the beta1,4 glycosidic bonds in the backbone of xylan. although xylanases from glycoside hydrolase family 11 (gh11) have been extensively studied, several issues remain unresolved. thus, the mechanism by which these enzymes hydrolyse decorated xylans is unclear and the structural basis for the variation in catalytic activity within this family is unknown. furthermore, the mechanism for the differences in the inhibition of fungal gh11 enzymes by the wh ... | 2008 | 18078955 |
| cloning of a rumen fungal xylanase gene and purification of the recombinant enzyme via artificial oil bodies. | a gene encoding a xylanase, named xyns20, was cloned from the ruminal fungus neocallimastix patriciarum. the dna sequence of xyns20 revealed that the gene was 1,008 bp in size and encoded amino acid sequences with a predicted molecular weight of 36 kda. the amino acid sequence alignment showed that the highest sequence identity (28.4%) is with insect gut xylanase xyl6805. according to the sequence-based classification, a putative conserved domain of glycosyl hydrolase family 11 was detected at t ... | 2008 | 18415096 |
| molecular cloning and characterization of a bifunctional xylanolytic enzyme from neocallimastix patriciarum. | a cdna encoding a bifunctional acetylxylan esterase/xylanase, xyns20e, was cloned from the ruminal fungus neocallimastix patriciarum. a putative conserved domain of carbohydrate esterase family 1 was observed at the n-terminus and a putative conserved domain of glycosyl hydrolase family 11 was detected at the c-terminus of xyns20e. to examine the enzyme activities, xyns20e was expressed in escherichia coli as a recombinant his(6) fusion protein and purified by immobilized metal ion-affinity chro ... | 2010 | 19690850 |
| potential hydrophobic interaction between two cysteines in interior hydrophobic region improves thermostability of a family 11 xylanase from neocallimastix patriciarum. | in this study, we employed directed evolution and site-directed mutagenesis to screen thermostable mutants of a family 11 xylanase from neocallimastix patriciarum, and found that the thermostability and specific activity are both enhanced when mutations (g201c and c60a) take place in the interior hydrophobic region of the enzyme. far-ultraviolet circular dichroism analysis showed that the melting temperatures (t(m)) of the g201c and c60a-g201c mutants are higher than that of the wild type by abo ... | 2010 | 19998284 |
| Functional characterization of cellulases identified from the cow rumen fungus Neocallimastix patriciarum W5 by transcriptomic and secretomic analyses. | ABSTRACT: | 2011 | 21849025 |
| structural analysis of a glycoside hydrolase family 11 xylanase from neocallimastix patriciarum: insights into the molecular basis of a thermophilic enzyme. | the catalytic domain of xyncdbfv, a glycoside hydrolase family 11 (gh11) xylanase from ruminal fungus neocallimastix patriciarum previously engineered to exhibit higher specific activity and broader ph adaptability, holds great potential in commercial applications. here, the crystal structures of xyncdbfv and its complex with substrate were determined to 1.27-1.43 å resolution. these structures revealed a typical gh11 β-jelly-roll fold and detailed interaction networks between the enzyme and lig ... | 2014 | 24619408 |
| effects of dietary cellulase and xylanase addition on digestion, rumen fermentation and methane emission in growing goats. | the objective of this study was to evaluate the effectiveness of supplementation of cellulase and xylanase to diets of growing goats to improve nutrient digestibility, utilisation of energy and mitigation of enteric methane emissions. the experiment was conducted in a 5 × 5 latin square design using five goats with permanent rumen fistulae and five treatments consisted of two levels of cellulase crossed over with two levels of xylanase plus unsupplemented control. the cellulase (243 u/g) derived ... | 2015 | 25963843 |
| highly divergent mitochondrion-related organelles in anaerobic parasitic protozoa. | the mitochondria have arisen as a consequence of endosymbiosis of an ancestral α-proteobacterium with a methane-producing archae. the main function of the canonical aerobic mitochondria include atp generation via oxidative phosphorylation, heme and phospholipid synthesis, calcium homeostasis, programmed cell death, and the formation of iron-sulfur clusters. under oxygen-restricted conditions, the mitochondrion has often undergone remarkable reductive alterations of its content and function, lead ... | 2014 | 24316280 |
| hydrolysis of wheat flour arabinoxylan, acid-debranched wheat flour arabinoxylan and arabino-xylo-oligosaccharides by β-xylanase, α-l-arabinofuranosidase and β-xylosidase. | a range of α-l-arabinofuranosyl-(1-4)-β-d-xylo-oligosaccharides (axos) were produced by hydrolysis of wheat flour arabinoxylan (wax) and acid debranched arabinoxylan (adwax), in the presence and absence of an axh-d3 α-l-arabinofuranosidase, by several gh10 and gh11 β-xylanases. the structures of the oligosaccharides were characterised by gc-ms and nmr and by hydrolysis by a range of α-l-arabinofuranosidases and β-xylosidase. the axos were purified and used to characterise the action patterns of ... | 2015 | 25723624 |
| cloning and characterization of a thermostable and ph-stable cellobiohydrolase from neocallimastix patriciarum j11. | an 1888-bp cdna designated cela, isolated from a cdna library of neocallimastix patriciarum j11 was cloned. the cela had an open reading frame of 1530 bp encoding j11 cela of 510 amino acids. the primary structure analysis of j11 cela revealed a complete cellulose-binding domain at the n-terminal, followed by an asn, ala, gly, gln and pro-rich linker and ending with a c-terminal glycosyl hydrolase family 6 catalytic domain. the mature j11 cela was overexpressed in escherichia coli and purified t ... | 2013 | 23770555 |
| catalytic efficiency diversification of duplicate β-1,3-1,4-glucanases from neocallimastix patriciarum j11. | four types of β-1,3-1,4 glucanase (β-glucanase, ec 3.2.1.73) genes, designated bgla13, bgla16, bgla51, and bglm2, were found in the cdna library of neocallimastix patriciarum j11. all were highly homologous with each other and demonstrated a close phylogenetic relationship with and a similar codon bias to streptococcus equinus. the presence of expansion and several predicted secondary structures in the 3' untranslated regions (3'utrs) of bgla16 and bglm2 suggest that these two genes were duplica ... | 2012 | 22492445 |
| a highly efficient β-glucosidase from the buffalo rumen fungus neocallimastix patriciarum w5. | cellulose, which is the most abundant renewable biomass on earth, is a potential bio-resource of alternative energy. the hydrolysis of plant polysaccharides is catalyzed by microbial cellulases, including endo-β-1,4-glucanases, cellobiohydrolases, cellodextrinases, and β-glucosidases. converting cellobiose by β-glucosidases is the key factor for reducing cellobiose inhibition and enhancing the efficiency of cellulolytic enzymes for cellulosic ethanol production. | 2012 | 22515264 |
| effects of dietary addition of cellulase and a saccharomyces cerevisiae fermentation product on nutrient digestibility, rumen fermentation and enteric methane emissions in growing goats. | this study was designed to assess the effectiveness of dietary cellulase (243 u/g, derived from neocallimastix patriciarum) and a saccharomyces cerevisiae fermentation product (yeast product) on ruminal fermentation characteristics, enteric methane (ch4) emissions and methanogenic community in growing goats. the experiment was conducted in a 5 × 5 latin square design using five xiangdong black wether goats. the treatments included a control and two levels of cellulase (0.8 g and 1.6 g/kg dry mat ... | 2016 | 27032031 |
| analysis and control of proteolysis of a fusion protein in pichia pastoris fed-batch processes. | a fusion protein composed of a cellulose-binding module (cbm) from neocallimastix patriciarum cellulase 6a and lipase b from candida antarctica (calb), was produced by pichia pastoris mut(+) in high-cell density bioreactor cultures. the production was induced by switching from growth on glycerol to growth on methanol. the lipase activity in the culture supernatant increased at an almost constant rate up to a value corresponding to 1.3 g x l(-1) of cbm-calb. however, only about 40% of the product ... | 2003 | 12668313 |
| improving the catalytic performance of a gh11 xylanase by rational protein engineering. | xyncdbfv from neocallimastix patriciarum is among the most effective xylanases and holds great potentials in a wide variety of industrial applications. in the present study, several active site residues were modified referring to the instrumental information of the complex structure of xyncdbfv and xylooligosaccharides. among the 12 single active site mutants, w125f and f163w show increased activity comparing to the wild-type protein. the double mutant w125f/f163w was then generated which displa ... | 2015 | 26088174 |
| antioxidant capacity of arabinoxylan oligosaccharide fractions prepared from wheat aleurone using trichoderma viride or neocallimastix patriciarum xylanase. | the effect of xylanase type (trichoderma viride or neocallimastix patriciarum) and graded ethanol fractionation on the antioxidant capacity (aoc) of arabinoxylan oligosaccharides (axos) obtained from wheat aleurone was investigated. axos yields were higher using n. patriciarum (62%) than t. viride (44%). the fraction (f100) collected at >80% ethanol concentration constituted 60% of total recovered axos. degree of substitution ranged from 0.20 to 0.60 for ethanol graded fractions. ferulic acid (f ... | 2015 | 25148993 |
| purification and characterization of a cellulolytic multienzyme complex produced by neocallimastix patriciarum j11. | understanding the roles of the components of the multienzyme complex of the anaerobial cellulase system, acting on complex substrates, is crucial to the development of efficient cellulase systems for industrial applications such as converting lignocellulose to sugars for bioethanol production. in this study, we purified the multienzyme complex of neocallimastix patriciarum j11 from a broth through cellulose affinity purification. the multienzyme complex is composed of at least 12 comprised prote ... | 2014 | 25073115 |
| expression of rumen microbial fibrolytic enzyme genes in probiotic lactobacillus reuteri. | this study was aimed at evaluating the cloning and expression of three rumen microbial fibrolytic enzyme genes in a strain of lactobacillus reuteri and investigating the probiotic characteristics of these genetically modified lactobacilli. the neocallimastix patriciarum xylanase gene xyncdbfv, the fibrobacter succinogenes beta-glucanase (1,3-1,4-beta-d-glucan 4-glucanohydrolase [ec 3.2.1.73]) gene, and the piromyces rhizinflata cellulase gene egla were cloned in a strain of l. reuteri isolated f ... | 2005 | 16269708 |
| characteristics of adjacent family 6 acetylxylan esterases from fibrobacter succinogenes and the interaction with the xyn10e xylanase in hydrolysis of acetylated xylan. | acetylxylan esterase genes axe6a and axe6b located adjacent to one another on a fibrobacter succinogenes chromosome have been separately cloned and their properties characterized. the corresponding esterases contained an n-terminal carbohydrate esterase family 6 catalytic domain (cd) and a c-terminal family 6 carbohydrate-binding module (cbm). the amino acid sequences of the cds and cbms were found to exhibit 52% and 40% amino acid similarity, respectively. the cds of the two esterases exhibited ... | 2005 | 16333341 |
| interfacing pichia pastoris cultivation with expanded bed adsorption. | for improved interfacing of the pichia pastoris fed-batch cultivation process with expanded bed adsorption (eba) technique, a modified cultivation technique was developed. the modification included the reduction of the medium salt concentration, which was then kept constant by regulating the medium conductivity at low value (about 8 ms/cm) by salt feeding. before loading, the low conductivity culture broth was diluted only to reduce viscosity, caused by high cell density. the concept was applied ... | 2006 | 16447173 |
| impact of an n-terminal extension on the stability and activity of the gh11 xylanase from thermobacillus xylanilyticus. | to understand structure-function relationships in the n-terminal region of gh11 xylanases, the 17 n-terminal amino acids of the gh11 xylanase from neocallimastix patriciarum (np-xyn) have been grafted onto the n-terminal extremity of the untypically short gh11 xylanase from thermobacillus xylanilyticus (tx-xyn), creating a hybrid enzyme denoted ntfus. the hybrid xylanase displayed properties (ph and temperature optima) similar to those of the parental enzyme, although thermostability was lowered ... | 2014 | 24440633 |