Publications

TitleAbstractYear
Filter
PMID
Filter
alpha-ketoglutarate metabolism by cytochrome-containing anaerobes.during growth in the presence of tracer amounts of exogenously supplied alpha-keto[1-14c]glutarate (akg) or alpha-keto [5-14c]glutarate, cytochrome-containing bacteroides fragilis strain 2044 and bacteroides vulgatus strain 8482 incorporated extremely small amounts of radioactivity into cell macromolecules and protoheme. under identical conditions, bacteroides "l" strain 7cm and bacteroides buccae strain j1 incorporated substantial label from [5-14c]akg, but not [1-14c]akg, into cellular macromo ...19836413047
effects of chetomin on growth and acidic fermentation products of rumen bacteria.chetomin, an antibiotic metabolite of chaetomium spp., was tested in the form of its tetrathiol derivative for its effects on growth and carbohydrate metabolism by five strains of functionally important rumen bacteria. the compound was bacteriostatic for the strains tested and gram-positive bacteria were more sensitive to inhibition than gram-negative bacteria. in an anaerobic broth dilution assay using a medium lacking rumen fluid, the minimum inhibitory concentration (mic) of chetomin which co ...19836686488
isolation of proteolytic rumen bacteria by use of selective medium containing leaf fraction 1 protein (ribulosebisphosphate carboxylase).the principle proteolytic bacteria isolated from bovine rumen contents by virtue of the ability to obtain nitrogen from the proteolysis of leaf fraction 1 protein (ribulosebisphosphate carboxylase, ec 4.1.1.39) were identified as streptococcus bovis and butyrivibrio spp. substitution of fresh fodder, rich in soluble protein, for a hay-concentrates diet resulted in enhanced ruminal proteolytic activity and a significant increase in the number of bacteria able to use fraction 1 protein as the sole ...19836881961
biohydrogenation of unsaturated fatty acids. purification and properties of cis-9,trans-11-octadecadienoate reductase.the enzyme catalyzing the second step in the biohydrogenation pathway of linoleic acid by butyrivibrio fibrosolvens cis-9,trans-11-octadecadienoate reductase has been purified to near homogeneity. it has a molecular weight of 60,000 and appears to be a single subunit. the purified enzyme contains 2 mol of iron, 10 mol of fucose, and 12 mol of galactose per 60,000 g. the iron, but not the carbohydrate, is required for enzymatic activity. phosphatidylethanolamine was also found to be associated wi ...19827061501
effect of ph on growth rates of rumen amylolytic and lactilytic bacteria.the relationship between the ph of the medium and specific growth rates, in well-buffered media at 38.5 degrees c, was determined for three strains of butyrivibrio fibrisolvens and for one strain each of streptococcus bovis, selenomonas ruminantium subsp. lactilytica. megasphaera elsdenii, veillonella alcalescens, and propionibacterium acnes. the ph optima for growth were between 6.1 and 6.6 for all six species, and the upper ph limits were between 7.3 and 7.8. the lower limit ph values for grow ...19827125656
an exopectate lyase of butyrivibrio fibrisolvens from the bovine rumen.an extracellular pectinolytic enzyme produced by butyrivibrio fibrisolvens isolated from the bovine rumen was studied. the enzyme had a ph optimum of 8.0 to 8.5 and was stimulated by ca2+ and inhibited by edta. the products of pectinolysis had an absorption peak at 235 nm and reacted with thiobarbituric acid, indicating a lyase type of action. the enzyme cleaved the substrates terminally from the reducing end; action on poly- and oligogalacturonates resulted in the formation of an unsaturated tr ...19827153760
isolation and presumptive identification of adherent epithelial bacteria ("epimural" bacteria) from the ovine rumen wall.one hundred sixty-one strains of adherent bacteria were isolated under anaerobic conditions from four sites on the rumen epithelial surface of sheep fed hay or a hay-grain ration. before isolation of bacteria, rumen tissue was washed six times in an anaerobic dilution solution, and viable bacteria suspended in the washings were counted. calculation indicated that unattached bacteria would have been removed from the tissue by this procedure, but a slow and progressive release of attached bacteria ...19817195191
characterization of the cecal bacteria of normal pigs.one hundred ninety-two isolates from cecal contents of three normal weaned pigs were obtained by means of anaerobic roll tube methods and were characterized. seventy-eight percent of the isolates were gram-negative. the most numerous species isolated from each of the pigs was bacteroides ruminicola. this species accounted for 35% of the isolates that were characterized, and selenomonas ruminantium accounted for 21% of the isolates. other gram-negative bacteria isolated from all three pigs were b ...19817235711
complex lipids of a lipolytic and general-fatty-acid-requiring butyrivibrio sp. isolated from the ovine rumen.the complex lipids of the naturally-occurring general-fatty-acid-auxotroph butyrivibrio s2 [hazlewood & dawson (1979) j. gen. microbiol. 112, 15-27] grown with palmitic acid as sole fatty-acid supplement have been investigated and some have been isolated in a state of purity and analysed. the majority are phospholipids (84%) and many contain galactose. they typically possess few esterified long-chain fatty-acid residues (c16:0), but are rich in esterified butyric acid and c16-alkenyl groups. mos ...19807236210
structure of diabolic acid-containing phospholipids isolated from butyrivibrio sp.the structures of the diabolic acid-containing phospholipids of buryrivibrio s2 grown in the presence of palmitic acid have been investigated. generally they consist of two conventional bacterial phospholipid or galactolipid structures linked by esterification through a single diabolic acid residue. the main lipid consists of the butyroyl ester of sn-1-alkenylglycero-3-phospho-1'-sn-glycerol joined in this way to the butyroyl ester of sn-1-alkenyl-3-galactosylglycerol by esterification of the va ...19807236211
effects of lasalocid or monensin on lactate-producing or -using rumen bacteria.lasalocid or monensin inhibited most of the lactate-producing rumen bacteria (butyrivibrio fibrisolvens, eubacterium cellulosolvens, e. ruminantium, lachnospira multiparus, lactobacillus ruminis, l. vitulinus, ruminococcus albus, r. flavefaciens, streptococcus bovis). minimum inhibitory concentrations ranged from .38 to 3.0 micrograms/ml. among the lactate producers, those that produce succinate as a major end product (bacteroides, selenomonas, succinimonas, succinivibrio) were not inhibited by ...19817275867
molybdate and sulfide inhibit h2 and increase formate production from glucose by ruminococcus albus.h2 production from glucose by ruminococcus albus was almost completely inhibited by 10(-5) m molybdate only when sulfide was present in the growth medium. inhibition was accompanied by a significant increase in the production of formate. extracts of molybdate-sulfide-grown cells did not contain hydrogenase activity. active enzyme in extracts of uninhibited cells was not inhibited by the molybdate-sulfide-containing growth medium. the results indicate that a complex formed from molybdate and sulf ...19807369826
identification of an endogenous electron donor for biohydrogenation as alpha-tocopherolquinol.four fluorescent compounds present in solvent extracts of butyrivibrio fibrisolvens could serve as electron donors for the biohydrogenation of cis-9,trans-11-octadecadienoate in the presence of dithionite, which was itself inactive. one of the compounds was identified as alpha-tocopherolquinol and another as alpha-tocopherolquinone. a partially purified soluble enzyme preparation from b. fibrisolvens catalyzed the reduction of alpha-tocopherolquinone to alpha-tocopherolquinol in the presence of ...19807372585
effect of ph on the efficiency of growth by pure cultures of rumen bacteria in continuous culture.a total of 10 strains of rumen bacteria, selenomonas ruminantium hd4, megasphaera elsdenii b159, butyrivibrio fibrisolvens a38, streptococcus bovis jb1, lactobacillus vitulinus ga1, bacteroides ruminicola b14, b. ruminicola ga33, ruminococcus albus 7, ruminococcus flavefaciens c94, and bacteroides succinogenes s85, were grown in energy-limiteh of the medium reservoir was lowered approximately 0.3 ph units, and the energy source concentration remaining in the culture vessel, optical density, cell ...19807387158
identification of deoxy-alpha-tocopherolquinol as another endogenous electron donor for biohydrogenation.solvent extracts of butyrivibrio fibrisolvens contain 2-[3, 7, 11, 15-tetramethylhexadecyl]-3, 5, 6-trimethyl-benzoquinol (deoxy-alpha-tocopherolquinol) that can serve as an alternate electron donor for alpha-tocopherolquinol for the biohydrogenation of cis-9, trans-11-octadecadienoate. in addition, the cell extracts contain deoxy-alpha-tocopherolquinone. this compound arises metabolically from alpha-tocopherolquinone via dehydration to trimethylphytylbenzoquinone followed by hydrogenation to de ...19807440571
degradation and utilization by butyrivibrio fibrisolvens h17c of xylans with different chemical and physical properties.hemicelluloses, mainly xylans, can be a major component of diets consumed by ruminants and undergo various degrees of microbial digestion in the rumen. the ability of butyrivibrio fibrisolvens, a major xylanolytic ruminal species, to degrade and utilize nine chemically and physically different xylans for growth was examined. the arabinoxylans used included two isolated from corncobs (ccx-a and ccx-b), a native xylan excreted by corn cell tissue cultures (cx), an oxalic acid-treated, arabinose-de ...19957487036
comparison of utilization of pectins from various sources by pure cultures of pectinolytic rumen bacteria and mixed cultures of rumen microorganisms.utilization of citrus, lucerne, apple and sugar beet pulp pectins by pure strains of rumen bacteria, prevotella ruminicola, lachnospira multiparus and butyrivibrio fibrisolvens was compared. additionally, the utilization of pectins by mixed rumen microorganisms was evaluated. the comparison was based on the depletion of galacturonic acid from medium, content of cellular protein in the cultures and the amount of end products of pectin fermentation in cell-free culture fluids. it was found that ci ...19947526615
engineering gut flora of ruminant livestock to reduce forage toxicity: progress and problems.the rumen bacterium butyrivibrio fibrosolvens has been genetically modified to detoxify fluoroacetate (a poisonous component of trees and shrubs in australia, africa and central america) and has been shown to persist when it is returned to the rumen. such bacteria may save animals from poisoning and, therefore, reduce economic losses for livestock industries in those countries. the ability to make genetic changes to rumen bacteria raises important questions about their practicality, and about th ...19957546565
fermentation of glucose and xylose in ruminal strains of butyrivibrio fibrisolvens.metabolism of glucose and xylose and parameters of growth were investigated in strains of butyrivibrio fibrisolvens atcc 19171 and ce 51. in the strain atcc 19171, the composition of fermentation end-products was the same in cultures supplied with glucose and xylose. the strain ce 51 produced more volatile fatty acids and less lactate from xylose than from glucose. cells of this strain grown on xylose possessed phosphoketolase activity (ec 4.1.2.9). in both strains the production of cell dry mat ...19957576521
cloning, sequencing, and characterization of a membrane-associated prevotella ruminicola b(1)4 beta-glucosidase with cellodextrinase and cyanoglycosidase activities.prevotella ruminicola b(1)4 is a gram-negative, anaerobic gastrointestinal bacterium. a 2.4-kbp chromosomal fragment from p. ruminicola encoding an 87-kda aryl-glucosidase (cdxa) with cellodextrinase activity was cloned into escherichia coli dh5 alpha and sequenced. cdxa activity was found predominantly in the membrane fraction of both p. ruminicola and e. coli, but p. ruminicola localized the protein extracellularly while e. coli did not. the hydrolase had the highest activity on cellodextrins ...19957592339
effect of extracellular lactate on growth of rumen lactate producers.the addition of na-lactate (50-150 mmol/l) to media with glucose had only marginal effect on the growth of rumen lactate-producing bacteria at ph between 6.5 and 5.8. butyrivibrio fibrisolvens was somewhat more sensitive to external lactate than streptococcus bovis, lactobacillus fermentum and selenomonas ruminantium. it can be concluded that rumen lactate producers, which proliferate at the onset of rumen lactic acidosis, are not influenced by the lactate accumulation, except some non-specific ...19947619002
a defined medium for rumen bacteria and identification of strains impaired in de novo biosynthesis of certain amino acids.a completely defined growth medium has been developed to determine the nitrogen requirements for several species of ruminal bacteria, and has revealed two strains which are impaired in de novo biosynthesis of certain amino acids. using nh4cl as a sole nitrogen source, the medium supported growth of butyrivibrio, selenomonas, prevotella and streptococcus species. one strain of b. fibrisolvens (e14) and one strain of p. ruminicola (ga33) did not grow in the presence of nh4cl until the medium was s ...19957639995
analysis of the sequence of a new cryptic plasmid, prjf2, from a rumen bacterium of the genus butyrivibrio: comparison with other butyrivibrio plasmids and application in the development of cloning vector.a small cryptic plasmid, prjf2, from butyrivibrio fibrisolvens strain ob157 was isolated and sequenced. the plasmid is similar in organisation to the previously sequenced butyrivibrio plasmid, prjf1, with two open reading frames, orf1 and orf2, flanking a region tentatively identified as the replication origin, and a region of unknown function defined by terminal 79 bp invert repeats. the sequences of orf1, orf2, and the presumptive replication origin are highly conserved. the sequence between t ...19957649434
identification of proteolytic rumen bacteria isolated from new zealand cattle.the protease activities of 212 strains of rumen bacteria isolated from new zealand cattle grazing pasture were measured. thirty-seven per cent of strains had activity greater than or equal to the proteolytic rumen bacterium prevotella ruminicola and 43 of these isolates were identified by morphology, carbon source utilization, gram stain, biochemical tests and fermentation end-product analysis. hierarchical cluster analysis showed that the strains formed four clusters: cluster a contained 26 str ...19957665388
development of a dna probe for streptococcus bovis by using a cloned amylase gene.streptococcus bovis is a normal inhabitant of the rumen but has been implicated as a causative agent for ruminal lactic acidosis and related problems. while rarely isolated from humans, s. bovis has been identified as a causative agent for endocarditis, meningitis, and septicemia. recent reports have also suggested a correlation between human colonic carcinoma and increased levels of s. bovis. identification of s. bovis strains of human origin has been problematic because of variations in result ...19937691873
partial purification and characterisation of bfi57i and bfi89i, restriction endonucleases from different strains of butyrivibrio fibrisolvens.two class-ii restriction endonucleases (enases), bfi57i and bfi89i, were partially purified from butyrivibrio fibrisolvens ob157 and ob189, respectively. bfi57i (isoschizomer sau3ai) had the dna recognition/cleavage sequence 5'-/gatc-3'; it is not inhibited by dam methylation, but is partially inhibited by m.bamhi methylation. bfi89i (isoschizomer eaei) had the recognition/cleavage sequence 5'-y/ggccr-3'; unlike the eaei isoschizomer it is not fully inhibited by m.haeiii methylation.19957698657
expression of the butyrivibrio fibrisolvens endo-beta-1,4-glucanase gene together with the erwinia pectate lyase and polygalacturonase genes in saccharomyces cerevisiae.recombinant saccharomyces cerevisiae strains capable of simultaneous secretion of bacterial glucanase and pectinase enzymes have been developed. the butyrivibrio fibrrisolvens endo-beta-1,4-glucanase gene (end1), the erwinia chrysanthemi pectate lyase gene (pele) and e. carotovora polygalacturonase gene (peh1) were each inserted between a yeast expression-secretion cassette and yeast gene terminator, and cloned into yeast-centromeric shuttle vectors. transcription initiation signals present in t ...19947750141
analyses of the gene and amino acid sequence of the prevotella (bacteroides) ruminicola 23 xylanase reveals unexpected homology with endoglucanases from other genera of bacteria.the dna sequence for the xylanase gene from prevotella (bacteroides) ruminicola 23 was determined. the xylanase gene encoded for a protein with a molecular weight of 65,740. an apparent leader sequence of 22 amino acids was observed. the promoter region for expression of the xylanase gene in bacteroides species was identified with a promoterless chloramphenicol acetyltransferase gene. a region of high amino acid homology was found with the proposed catalytic domain of endoglucanases from several ...19937763664
detoxification of the plant toxin fluoroacetate by a genetically modified rumen bacterium.we isolated the fluoroacetate dehalogenase gene (h1), from moraxella species strain b, and placed it under the transcriptional control of a 154 bp fragment of the erm gene promoter. the promoter/gene construct was attached to the butyrivibrio fibrisolvens shuttle vector pbherm, and the resulting dehalogenase expression plasmid (pbhf) was transferred to b. fibrisolvens ob156 by electroporation. the erm gene promoter directed expression of dehalogenase activity in both e. coli and b. fibrisolvens ...19947765567
a stable and efficient transformation system for butyrivibrio fibrisolvens ob156.a 9.5-kb shuttle vector capable of replication and selection in both escherichia coli and butyrivibrio fibrisolvens was constructed. plasmid puc118 provided replication functions and ampicillin resistance selection in e. coli. in b. fibrisolvens, replication was controlled by the native plasmid prjf1 from strain ob156, and selectability was provided by a 3.5-kb fragment of plasmid pam beta 1 containing the erythromycin resistance gene. optimum conditions for transformation were 15 kv/cm, 2 h rec ...19957765886
isolation and characteristics of a wheatbran-degrading butyrivibrio from human faeces.screening over 100 isolates from human faeces for cellulolytic activity led to the isolation of a weakly cellulolytic anaerobic, curved, motile bacterium which produced h2, lactate and butyrate from wheatbran. the mol% of g + c in the dna was 39-42. these properties, together with the gram-positive cell wall ultrastructure and sds-page profile, are consistent with the genus butyrivibrio. the isolate is believed to be the most active wheatbran-degrading bacterium so far described.19957766117
response to various amounts of aspergillus oryzae fermentation extract on ruminal metabolism in cattle.the objective of this study was to determine whether aspergillus oryzae fermentation extract stimulated or inhibited ruminal fermentation when fed at higher than recommended doses (3 g/d). four dietary treatments of a. oryzae fermentation extract were fed daily to six cows fitted with ruminal cannulas. for each of four periods, bromegrass hay (6% cp) with and without extract was fed for 28 d. dacron bags containing bromegrass cell walls were ruminally incubated to determine ruminal fiber degrada ...19947836596
cyclic amp in ruminal and other anaerobic bacteria.an examination of camp levels in predominant species of ruminal bacteria and other anaerobic bacteria was conducted. cellular camp concentrations of glucose-grown cultures of butyrivibrio fibrisolvens 49, prevotella ruminicola d31d, selenomonas ruminantium hd4 and d, megasphaera elsdenii b159, streptococcus bovis jb1, bacteroides thetaiotaomicron 5482, and clostridium acetobutylicum atcc 824 were determined at various times during growth by a competitive binding radioimmunoassay procedure. the r ...19947851742
gene sequence and analysis of protein domains of egb, a novel family e endoglucanase from fibrobacter succinogenes s85.the endoglucanase gene (endb) of fibrobacter succinogenes s85 encodes a protein of 555 amino acids (egb) with a m(r) of 62,500. egb shows homology with cellulases belonging to family e. residues involved in the catalytic activity of celd from clostridium thermocellum are also found in egb. structure predictions suggest that egb, like celd, comprises a large alpha-helical catalytic domain plus a beta-strand domain of unknown function located in the n-terminal part of the protein. construction of ...19947851752
a conjugative transfer system for the rumen bacterium, butyrivibrio fibrisolvens, based on tn916-mediated transfer of the staphylococcus aureus plasmid pub110.a limitation of genetic studies of the rumen bacterium, butyrivibrio fibrisolvens, has been the availability of suitable vectors and transfer systems. using the conjugative tetracycline resistant transposon, tn916, the staphylococcus aureus plasmid, pub110, and the pub110-based shuttle vector, publrs, a conjugative transfer system was developed for b. fibrisolvens. b fibrisolvens donor strains h17c2 and h17c12, containing tn916 and pub110 or publrs, respectively, were used in mating experiments ...19947899514
a new type of glutamine synthetase in cyanobacteria: the protein encoded by the glnn gene supports nitrogen assimilation in synechocystis sp. strain pcc 6803.a new glutamine synthetase gene, glnn, which encodes a polypeptide of 724 amino acid residues (m(r), 79,416), has been identified in the unicellular cyanobacterium synechocystis sp. strain pcc 6803; this is the second gene that encodes a glutamine synthetase (gs) in this cyanobacterium. the functionality of this gene was evidenced by its ability to complement an escherichia coli glna mutant and to support synechocystis growth in a strain whose glna gene was inactivated by insertional mutagenesis ...19947906687
sequence similarities and evolutionary relationships of microbial, plant and animal alpha-amylases.amino acid sequence comparison of 37 alpha-amylases from microbial, plant and animal sources was performed to identify their mutual sequence similarities in addition to the five already described conserved regions. these sequence regions were examined from structure/function and evolutionary perspectives. an unrooted evolutionary tree of alpha-amylases was constructed on a subset of 55 residues from the alignment of sequence similarities along with conserved regions. the most important new infor ...19947925367
pentose transport by the ruminal bacterium butyrivibrio fibrisolvens.butyrivibrio fibrisolvens is a fibrolytic ruminal bacterium that degrades hemicellulose and ferments the resulting pentose sugars. washed cells of strain d1 accumulated radiolabelled xylose (km = 1.5 microm) and arabinose (km = 0.2 microm) when the organism was grown on xylose, arabinose, or glucose, but cultures grown on sucrose or cellobiose had little capacity to transport pentose. glucose and xylose inhibited transport of each other non-competitively. both sugars were utilized preferentially ...19947988863
influence of yucca shidigera extract on ruminal ammonia concentrations and ruminal microorganisms.an extract of the desert plant yucca shidigera was assessed for its possible benefit in ruminal fermentation. the extract bound ammonia in aqueous solution when concentrations of ammonia were low (up to 0.4 mm) and when the extract was added at a high concentration to the sample (20%, vol/vol). the apparent ammonia-binding capability was retained after autoclaving and was decreased slightly following dialysis. acid-precipitated extract was inactive. no evidence of substantial ammonia binding was ...19948031077
features of the cellodextrinase gene from fibrobacter succinogenes s85.the nucleotide sequence of a 2.3-kb dna fragment containing a cellodextrinase gene (ceda) from the ruminal anaerobe fibrobacter succinogenes s85 was determined. activity was expressed from this fragment when it was cloned in both orientations in pbluescript ks+ and sk-, indicating a functional f. succinogenes promoter in escherichia coli. promoter sequences (ttgaaca and aataa) were identified upstream of the atg initiation codon preceded by a putative ribosome binding site. the ceda open reading ...19948076254
cloning and nucleotide sequence of the butyrivibrio fibrisolvens gene encoding a type iii glutamine synthetase.a butyrivibrio fibrisolvens glna gene encoding glutamine synthetase (gs) was cloned on a recombinant plasmid pgs4 which enabled escherichia coli glna deletion mutants to utilize (nh4)2so4 as a sole source of nitrogen. the nucleotide sequence of a 2423 bp dna segment containing the gs-coding region of b. fibrisolvens was determined and the complete amino acid sequence (701 residues) was deduced. comparisons of the derived b. fibrisolvens gs protein sequence with the amino acid sequences of gs fro ...19938103789
interactions between rumen bacterial strains during the degradation and utilization of the monosaccharides of barley straw cell-walls.pure cultures and pair-combinations of strains representative of the rumen cellulolytic species ruminococcus flavefaciens, fibrobacter succinogenes and butyrivibrio fibrisolvens were grown on cell-wall materials from barley straw. of the pure cultures, r. flavefaciens solubilized straw most rapidly. the presence of b. fibrisolvens, which was unable to degrade straw extensively in pure culture, increased the solubilization of dry matter by r. flavefaciens and the solubilization of cell-wall carbo ...19948157547
interactions between proteolytic and cellulolytic rumen bacteria during hydrolysis of plant cell wall protein.during the degradation of the plant cell wall protein of dried alfalfa, interactions may occur between hydrolytic activities of cellulolytic (ruminococcus albus or fibrobacter succinogenes) and proteolytic (prevotella ruminicola or butyrivibrio fibrisolvens) bacteria. in vitro the hydrolysis of these protein compounds begins after the depolymerization of the cell wall polysaccharides has started. maximal degradation of cell wall protein of dried alfalfa (37.2%) was obtained with cocultures of pr ...19938216756
digestion of cell-wall monosaccharides of ryegrass and alfalfa hays by the ruminal bacteria fibrobacter succinogenes and butyrivibrio fibrisolvens.the ruminal bacteria fibrobacter succinogenes strains s85 and bl2 were grown in monocultures or in coculture with strain d1 of butyrivibrio fibrisolvens, and the solubilization of ryegrass and alfalfa cell walls (cw) and digestion of cw monosaccharides were measured. fibrobacter succinogenes monocultures and cocultures with b. fibrisolvens d1 degraded 58-69% of ryegrass cw, solubilizing 67-78% of cw glucose, 65-71% of cw xylose, 69-75% of hemicellulose, and 68-77% of total cw monosaccharides. wh ...19938221378
characterization of the cell wall of butyrivibrio species.most butyrivibrio strains have been isolated from the gastrointestinal tract of animals and have been classified as butyrivibrio fibrisolvens. a few strains isolated from human feces are designated as butyrivibrio crossatus, the other species in this genus. butyrivibrio fibrisolvens strains are anaerobic, curved rods that produce butyrate, but numerous studies have shown that these strains display considerable variations in phenotypic properties and heterogeneity in dna relatedness. although ove ...19938261331
xylose and arabinose utilization by the rumen bacterium butyrivibrio fibrisolvens.the rumen bacterium butyrivibrio fibrisolvens strain d1 co-utilized xylose and glucose in batch culture, but there was a marked preference for glucose over arabinose. when both pentoses were provided, xylose was preferred over arabinose. strain d1 co-utilized a combination of either pentose and cellobiose, but preferred over maltose. pentose sugars were depleted less rapidly in the presence of sucrose than controls containing only pentose. in contrast, b. fibrisolvens strain a38 exhibited a stro ...19938270194
utilization of xylooligosaccharides by selected ruminal bacteria.the ability of ruminal bacteria to utilize xylooligosaccharides was examined. xylooligosaccharides were prepared by partially hydrolyzing oat spelt xylan in phosphoric acid. this substrate solution was added (0.2%, wt/vol) to a complex medium containing yeast extract and trypticase that was inoculated with individual species of ruminal bacteria, and growth and utilization were monitored over time. all of the xylanolytic bacteria examined were able to utilize this oligosaccharide mixture as a gro ...19938285663
transcriptional regulation of an endoglucanase and a cellodextrinase gene in ruminococcus flavefaciens fd-1.a gene which encodes a 35 kda protein with both carboxymethylcellulase and xylanase activity was cloned from ruminococcus flavefaciens fd-1 and the nucleotide sequence determined. the fd-1 gene, cele, and the cela gene, which encodes a cellodextrinase, were used as probes to analyse transcription in r. flavefaciens grown under different conditions. transcription of both genes was induced when cellulose was added to cells growing in cellobiose. this induction continued after cellulose depletion a ...19938360615
simultaneous high-performance liquid chromatographic determination of both the cleavage pattern and the stereochemical outcome of the hydrolysis reactions catalyzed by various glycosidases.a high-performance liquid chromatographic method for the simultaneous determination of both the stereochemical outcome and the cleavage pattern of enzymatic action on unmodified sugar substrates is described. three different enzymes were investigated by this method. human pancreatic alpha-amylase hydrolyzed maltopentaose with retention of anomeric configuration, with the cleavage position being two glucose units from the reducing end. cellulomonas fimi endoglucanase d hydrolyzed cellopentaose wi ...19938368500
structural studies of the extracellular polysaccharide from butyrivibrio fibrisolvens strain x6c61.the capsular polysaccharide from butyrivibrio fibrisolvens strain x6c61 has been investigated using nmr spectroscopy, mass spectrometry, methylation analysis, and partial acid hydrolysis as the main methods. the polysaccharide is composed of hexasaccharide repeating units having the following structure. [formula: see text] the polysaccharide also contains o-acetyl groups, of which approximately 70% are substituted to o-3 of the beta-d-glc pa residue.19938370042
p-coumaroyl and feruloyl arabinoxylans from plant cell walls as substrates for ruminal bacteria.growth of the ruminal bacteria ruminococcus flavefaciens fd1, selenomonas ruminantium hd4, and butyrivibrio fibrisolvens 49 was limited by ester-linked feruloyl and p-coumaroyl groups. the limitation of growth on phenolic acid-carbohydrate complexes varied with individual bacteria and appeared to be influenced by ability to hydrolyze carbohydrate linkages.19938434931
the complete nucleotide sequence of a small cryptic plasmid from a rumen bacterium of the genus butyrivibrio.the complete nucleotide sequence of a plasmid, designated prjf1, isolated from a rumen bacterium of the genus butyrivibrio, has been determined. prjf1 is a small plasmid (2631 bp) which shows the high at content (64%) typical of plasmids from gram-positive organisms. computer analysis of sequence data revealed two major open reading frames encoded on the same strand but in different frames. the smaller, orf1 (435 bp), is preceded by shine dalgarno (sd) and escherichia coli-10, -35 sequences and ...19938441770
degradation and utilization of xylan by the ruminal bacteria butyrivibrio fibrisolvens and selenomonas ruminantium.the cross-feeding of xyland hydrolysis products between the xylanolytic bacterium butyrivibrio fibrisolvens h17c and the xylooligosaccharide-fermenting bacterium selenomonas ruminantium ga192 was investigated. cultures were grown anaerobically in complex medium containing oat spelt xylan, and the digestion of xylan and the generation and subsequent utilization of xylooligosaccharide intermediates were monitored over time. monocultures of b. fibrisolvens rapidly degraded oat spelt xylan, and a po ...19958534103
structural studies of the extracellular polysaccharide from butyrivibrio fibrisolvens strain 49.the structure of butyrivibrio fibrisolvens strain 49 capsular polysaccharide has been investigated mainly by sugar and methylation analysis, partial chemical degradations, nmr spectroscopy, and mass spectrometry. the results suggest that the polysaccharide is composed of pentasaccharide repeating units having the following structure. [formula: see text] the polysaccharide contains o-acetyl groups, one of which is substituted to o-3 of the 4-substituted alpha-d-galp residue, while others occur in ...19958536266
a sequence analysis of the beta-glucosidase sub-family b.this computational study is a summary of structural properties of the beta-glucosidase subfamily b. computations were carried out using gcg package programs. all sequences used in this analysis were taken from the protein data bank. the multialignment and the phylogenetic tree of the beta-glucosidase sub-family b are shown. the conserved patterns: dgp, grnfe, dpyl, khf, sdw, gld, vllkn in the n-terminal region and fgyglsy in the c-terminal part should be pointed out. c-terminal parts of the buty ...19968549811
genetic analysis of the minimal replicon of plasmid pip417 and comparison with the other encoding 5-nitroimidazole resistance plasmids from bacteroides spp.the nucleotide sequence of the dna replication origin region of a bacteroides vulgatus plasmid, pip417, encoding 5-nitroimidazole resistance has been determined. this region of 1934 bp presents some characteristics similar to those of other replication protein-dependent origins. it contains a large open reading frame which could encode a basic rep protein (repa) of 36.8 kda. upstream of this orf exist an at-rich region, three direct repeats (iterons) of 21 bp, multiple dnaa binding sites, and si ...19958559801
phylogenetic analysis of butyrivibrio strains reveals three distinct groups of species within the clostridium subphylum of the gram-positive bacteria.the phylogenetic positions of 40 butyrivibrio strains were determined by performing a comparative sequence analysis of the 16s rrna genes of these organisms. we found that all of the strains which we studied belong to cluster xiva (m. d. collins, p. a. lawson, a. willems, j. j. cordoba, j. fernandez=garayzabal, p. garcia, j. cai, h. hippe, and j. a. e. farrow, int. j. syst. bacteriol. 44:812-826, 1994) of the clostridium subphylum of the gram-positive bacteria, which also includes several clostr ...19968573495
rumen fermentation and metabolic profile in conventional and gnotobiotic lambs.observations were carried out of actual acidity, volatile fatty acid (vfa) concentrations, enzyme activity in the rumen, total protein, urea, total lipid and glucose in the serum of conventional (cl) and gnotobiotic lambs (gl) in the period of milk nutrition. the inoculum of gnotobiotic lambs contained streptococcus bovis, prevoxella ruminicola, butyrivibrio fibrisolvens and selenomonas ruminantium at a concentration of 1.10(6) each. throughout the observation period the ph of the rumen contents ...19958585797
stereochemical course and reaction products of the action of beta-xylosidase from thermoanaerobacterium saccharolyticum strain b6a-ri.beta-xylosidases are grouped in families 39 and 43 of a general classification of glycosyl hydrolases based on amino acid sequence similarities. the beta-xylosidase from butyrivibrio fibrisolvens, which belongs to family 43, has been shown to operate by a molecular mechanism which results in the inversion of the anomeric configuration. thermoanaerobacterium saccharolyticum b6a-ri beta-xylosidase which belongs to family 39 was purified as a recombinant enzyme from escherichia coli. the stereochem ...19968612648
structural organization of pram4, a cryptic plasmid from prevotella ruminicola.a total of 530 strains of rumen bacteria were screened for the presence of plasmid dna. the percentage of plasmid-bearing strains was found to be the highest among the bacteroides/ prevotella group (9.9%), while it was less than 1% in the butyrivibrio (0.2%) and clostridium (0.6%) genera. a small cryptic plasmid pram4 from prevotella ruminicola t31 was subcloned in escherichia coli and completely sequenced. two open reading frames, encoding potential polypeptides of m(r) 32,322 (orf1) and 32,122 ...19968700970
co-expression of a phanerochaete chrysosporium cellobiohydrolase gene and a butyrivibrio fibrisolvens endo-beta-1,4-glucanase gene in saccharomyces cerevisiae.a cdna fragment encoding the phanerochaete chrysosporium cellobiohydrolase (cbh1-4) was amplified and cloned with the aid of the polymerase chain reaction (pcr) technique. the cbh1-4 gene and the butyrivibrio fibrisolvens endo-beta-1,4-glucanase (end1) gene were successfully expressed in saccharomyces cerevisiae under the control of the phosphoglycerate kinase-i (pgk1) and alcohol dehydrogenase-ii (adh2) gene promoters and terminators, respectively. the native p. chrysosporium signal sequence me ...19968753654
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 ...19968837463
how many ruminal bacteria are there?with the development of strictly anaerobic techniques and habitat-simulating media, a variety of bacteria were isolated from the rumen in the 1940s and 1950s. based on standard morphological and physiological characteristics, the microbial ecosystem of the rumen contains a very complex population of bacteria. in recent years, ruminal bacteria have been re-evaluated with newer, more objective, and genetically valid methods of classification. ribosomes are complicated structures, and their dna-enc ...19968880472
characterization of proteolytic activities of rumen bacterial isolates from forage-fed cattle.the proteolytic activities of eight strains of ruminal bacteria isolated from new zealand cattle were characterized with respect to their cellular location, response to proteinase inhibitors and hydrolysis of artificial proteinase substrates. the streptococcus bovis strains had predominantly cell-bound activity, which included a mixture of serine and cysteine-type proteinases which had high activity against leucine p-nitroanilide (lpna). the eubacterium strains had a mainly cell-associated activ ...19968939033
16s rdna analysis of butyrivibrio fibrisolvens: phylogenetic position and relation to butyrate-producing anaerobic bacteria from the rumen of white-tailed deer.complete 16s rdna sequences of six strains of butyrivibrio fibrisolvens, including the type strain (atcc 19171), were determined. the type strain was found to have less than 89% sequence similarity to the other isolates that were examined. the five plasmid-bearing strains formed a closely related cluster and three of these strains (ob156, ob157 and ob192) were very highly related (> 99%), indicating that they are isolates of the same genomic species. the phylogenetic position of butyrivibrio was ...19968987694
cloning of cellobiose phosphoenolpyruvate-dependent phosphotransferase genes: functional expression in recombinant escherichia coli and identification of a putative binding region for disaccharides.genomic libraries from nine cellobiose-metabolizing bacteria were screened for cellobiose utilization. positive clones were recovered from six libraries, all of which encode phosphoenolpyruvate:carbohydrate phosphotransferase system (pts) proteins. clones from bacillus subtilis, butyrivibrio fibrisolvens, and klebsiella oxytoca allowed the growth of recombinant escherichia coli in cellobiose-m9 minimal medium. the k. oxytoca clone, ploi1906, exhibited an unusually broad substrate range (cellobio ...19979023916
isolation and characterization of a bacteriocin (butyrivibriocin ar10) from the ruminal anaerobe butyrivibrio fibrisolvens ar10: evidence in support of the widespread occurrence of bacteriocin-like activity among ruminal isolates of b. fibrisolvens.forty-nine isolates of butyrivibrio fibrisolvens and a single isolate of butyrivibrio crossotus were screened for the production of inhibitors by a deferred plating procedure. twenty-five isolates produced factors which, to various degrees, inhibited the growth of the other butyrivibrio isolates. none of the inhibitory activity was due to bacteriophages. the inhibitory products from 18 of the producing strains were sensitive to protease digestion. differences in the ranges of activity among the ...19979023920
are ruminal bacteria armed with bacteriocins?the production of toxic compounds or antibiotics is a common component of intermicrobial competitive interactions, and many of these toxins have been adopted and adapted for the control of microbial populations. one class of these toxins, the bacteriocins, is a heterogeneous group of proteinaceous antibiotics that often display a high degree of target specificity, although many have a very wide spectrum of activity. to date, only limited information is available concerning the occurrence of bact ...19969029368
group-specific 16s rrna hybridization probes for determinative and community structure studies of butyrivibrio fibrisolvens in the rumen.oligonucleotide probes covering three phylogenetically defined groups of butyrivibrio spp. were successfully designed and tested. the specificity of each probe was examined by hybridization to rrnas from an assortment of b. fibrisolvens isolates as well as additional ruminal and nonruminal bacteria. the sensitivity of the hybridization method was determined by using one of the probes (probe 156). when rna was extracted from a culture of ob156, the probe was able to detect target cells at densiti ...19979097421
expression of a butyrivibrio fibrisolvens e14 gene (cinb) encoding an enzyme with cinnamoyl ester hydrolase activity is negatively regulated by the product of an adjacent gene (cinr).a second cinnamoyl ester hydrolase (ceh) encoding gene (cinb) has been characterized from the ruminal bacterium butyrivibrio fibrisolvens e14. cinb is more similar to cina (previously named cini) (28% amino acid identify), the first ceh described from b. fibrisolvens e14, than either of the enzymes are to any other member of the family of hydrolases to which they belong. upstream of cinb, and in the opposite orientation, is a gene (cinr) encoding a protein with substantial similarity to members ...19979141683
sequence analysis and characterization of pom1, a small cryptic plasmid from butyrivibrio fibrisolvens, and its use in construction of a new family of cloning vectors for butyrivibrios.as a preliminary step in the development of vector systems, we have isolated and begun to characterize small, cryptic plasmids from several strains of the rumen bacterium butyrivibrio fibrisolvens. we present here the complete nucleotide sequence of butyrivibrio plasmid pom1, which was isolated from b. fibrisolvens bu49. while it is very similar in size to the previously characterized butyrivibrio plasmids prjf1 and prjf2, pom1 exhibits a restriction pattern which is quite distinct. analysis of ...19979143105
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 ...19979195758
over-expression of the saccharomyces cerevisiae exo-beta-1,3-glucanase gene together with the bacillus subtilis endo-beta-1,3-1,4-glucanase gene and the butyrivibrio fibrisolvens endo-beta-1,4-glucanase gene in yeast.the exg1 gene encoding the main saccharomyces cerevisiae exo-beta-1,3-glucanase was cloned and over-expressed in yeast. the bacillus subtilis endo-1,3-1,4-beta-glucanase gene (beg1) and the butyrivibrio fibrisolvens endo-beta-1,4-glucanase gene (end1) were fused to the secretion signal sequence of the yeast mating pheromone alpha-factor (mf alpha 1s) and inserted between the yeast alcohol dehydrogenase ii gene promoter (adh2p) and terminator (adh2t). constructs adh2p-mf alpha 1s-beg1-adh2t and a ...19979226961
stoichiometry of glucose and xylose fermentation in butyrivibrio fibrisolvens 787.glucose and xylose are the principal monomeric units of plant carbohydrates. butyrivibrio fibrisolvens, an important rumen bacterium, converted both sugars to formate, acetate, butyrate and lactate. more metabolites and less cell biomass was formed from xylose than from glucose. in cultures with both substrates, glucose was utilized preferentially. growth on glucose was more rapid than on xylose. no phosphoketolase activity (ec 4.1.2.9) was detected in this strain. more carbohydrate and less pro ...19969229858
structural studies of the extracellular polysaccharide from butyrivibrio fibrisolvens strain cf3.the structure of the butyrivibrio fibrisolvens strain cf3 capsular polysaccharide has been investigated mainly by sugar and methylation analyses, smith degradation, nmr spectroscopy, and mass spectrometry. the results indicate that the polysaccharide is composed of pentasaccharide repeating units having the following structure: -->4)-beta-l-altp-(1-->4)-beta-d-glcp-(1-->3)-4-o-[(r)-1-carboxyet hyl]-beta- d-glcp-(1-->4)-6-o-[(r)-1-carboxyethyl]-alpha-d-galp-(1--> 2 increases 1 beta-d-glcp.19979232840
high-frequency transfer of a naturally occurring chromosomal tetracycline resistance element in the ruminal anaerobe butyrivibrio fibrisolvens.butyrivibrio fibrisolvens strains resistant to tetracycline were isolated from the bovine rumen. two of three tcr b. fibrisolvens tested were able to donate tetracycline resistance at frequencies ranging from 10(-7) to 10(-1) per donor cell in anaerobic filter matings to a rifampin-resistant mutant of the type strain of b.fibrisolvens, 2221r. the recipient strain 2221r exhibited rapid autoaggregation, which might be a factor in the high transfer rates observed. tcr transconjugants of b. fibrisol ...19979292992
microbial perspective on fiber utilization by swine.dietary fiber may contribute up to 30% of the maintenance energy needs of growing pigs. higher energy contributions may be obtained from dietary fiber fed to sows, along with some improvements in reproduction, health, and well-being. as long as cereal grain supplies and high-quality protein supplements are abundant, the use of fibrous feeds for swine most likely will be limited. however, as the human demand for cereal grains increases, swine producers, especially those with reproductive animals, ...19979331875
engineering yeast for efficient cellulose degradation.saccharomyces cerevisiae produces several beta-1,3-glucanases, but lacks the multicomponent cellulase complexes that hydrolyse the beta-1,4-linked glucose polymers present in cellulose-rich biomass as well as in haze-forming glucans in certain wines and beers. we have introduced into s. cerevisiae a functional cellulase complex for efficient cellulose degradation by cloning the endomyces fibuliger cellobiase (bgl1) gene and co-expressing it with the butyrivibrio fibrisolvens endo-beta-1,4-glucan ...19989483796
constitutive expression of a heterologous eubacterium ruminantium xylanase gene (xyna) in butyrivibrio fibrisolvens.an eubacterium ruminantium xylanase gene (xyna) was inserted into pyk4, a shuttle vector replicable in both escherichia coli and butyrivibrio fibrisolvens, and the resultant chimeric plasmid (pyk4xt) was electroporated into b. fibrisolvens ob156c in an attempt to obtain a more xylanolytic b. fibrisolvens. electrotransformants were screened by the development of erythromycin resistance, followed by an activity staining and southern hybridization. the presence of mrna from xyna in the transformant ...19989631539
genetically modified ruminal bacteria protect sheep from fluoroacetate poisoning.four strains of butyrivibrio fibrisolvens, transformed with a gene encoding fluoroacetate dehalogenase, maintained a combined population of 10(6) to 10(7) cells ml-1 in the rumens of test sheep. five inoculated sheep showed markedly reduced toxicological symptoms after fluoroacetate poisoning when behavioral, physiological, and histological effects were compared with those of five uninoculated control sheep.19989726903
sequence analysis of small cryptic plasmids isolated from selenomonas ruminantium s20.two small cryptic plasmids designated pone429 and pone430 were isolated from a rumen bacterium, selenomonas ruminantium s20. the complete sequence of pone429 was 2100 bp and contained one open reading frame (orf) of 201 amino acids. the sequence of pone430 had 1527 bp and one orf of 171 amino acids with the similarity of replication protein (rep protein) of pom1, psn2, and pim13 isolated from butyrivibrio fibrisolvens, staphylococcus aureus, and bacillus subtilis, respectively. in these plasmids ...19999871109
evidence for production of a new lantibiotic (butyrivibriocin or79a) by the ruminal anaerobe butyrivibrio fibrisolvens or79: characterization of the structural gene encoding butyrivibriocin or79a.the ruminal anaerobe butyrivibrio fibrisolvens or79 produces a bacteriocin-like activity demonstrating a very broad spectrum of activity. an inhibitor was isolated from spent culture fluid by a combination of ammonium sulfate and acidic precipitations, reverse-phase chromatography, and high-resolution gel filtration. n-terminal analysis of the isolated inhibitor yielded a 15-amino-acid sequence (g-n/q-g/p-v-i-l-x-i-x-h-e-x-s-m-n). two different amino acid residues were detected in the second and ...199910224011
alternative schemes of butyrate production in butyrivibrio fibrisolvens and their relationship to acetate utilization, lactate production, and phylogeny.butyrivibrio fibrisolvens strains d1 and a38 produced little lactate, but strain 49 converted as much as 75% of its glucose to lactate. strain 49 had tenfold more lactate dehydrogenase activity than strains d1 or a38, this activity was stimulated by fructose 1,6-bisphosphate, and had a ph optimum of 6.25. a role for fructose 1,6-bisphosphate or ph regulation of lactate production in strain 49 was, however, contradicted by the observations that very low concentrations (< 0.2 mm) of fructose 1,6-b ...199910382263
distribution and evolution of the xylanase genes xyna and xynb and their homologues in strains of butyrivibrio fibrisolvens.the ruminal bacterium butyrivibrio fibrisolvens is being engineered by the introduction of heterologous xylanase genes in an attempt to improve the utilization of plant material in ruminants. however, relatively little is known about the diversity and distribution of the native xylanase genes in strains of b. fibrisolvens. in order to identify the most appropriate hosts for such modifications, the xylanase genotypes of 28 strains from the three 16s ribosomal dna (rdna) subgroups of butyrivibrio ...199910427063
the ability of "low g + c gram-positive" ruminal bacteria to resist monensin and counteract potassium depletion.gram-negative ruminal bacteria with an outer membrane are generally more resistant to the feed additive, monensin, than gram-positive species, but some bacteria can adapt and increase their resistance. 16s rrna sequencing indicates that a variety of ruminal bacteria are found in the "low g + c gram-positive group," but some of these bacteria are monensin resistant and were previously described as gram-negative species (e.g., selenomonas ruminantium and megasphaera elsdenii). the activity of mone ...199910486059
feasibility of using total purines as a marker for ruminal bacteria.a procedure for measuring total purine content of mixed ruminal bacteria was adapted for use in the determination of purines in pure cultures of ruminal bacteria. recovery of adenine and guanine, alone or in mixture, was quite variable. the problem was traced to solubility of the silver salt of adenine in the acid wash solution. when the precipitating solution was used as the wash, recovery of the purines was over 97%. recovery of a 1:1 mixture of adenine and guanine added to yeast rna was 100.6 ...199910568481
construction of a promoter-rescue plasmid for butyrivibrio fibrisolvens and its use in characterization of a flagellin promoter.the butyrivibrio fibrisolvens/escherichia coli shuttle vector pbherm has been modified to produce a plasmid (pbhe) that can be used for the identification and characterization of promoters in b. fibrisolvens. pbhe allows the insertion of a test promoter immediately upstream of a promoterless erythromycin resistance gene (ermam). the efficacy of the pbhe plasmid in isolating and characterizing promoters was tested by inserting the flagellin gene (flaa) promoter from b. fibrisolvens or77. transcri ...200010679047
occurrence of the new tetracycline resistance gene tet(w) in bacteria from the human gut.members of our group recently identified a new tetracycline resistance gene, tet(w), in three genera of rumen obligate anaerobes. here, we show that tet(w) is also present in bacteria isolated from human feces. the tet(w) genes found in human fusobacterium prausnitzii and bifidobacterium longum isolates were more than 99.9% identical to those from a rumen isolate of butyrivibrio fibrisolvens.200010681357
effects of ammonia and amino acids on the growth and proteolytic activity of three species of rumen bacteria: prevotella albensis, butyrivibrio fibrisolvens, and streptococcus bovis.the addition of increasing physiological concentrations of ammonia or amino acids had distinct effects on the growth and proteolytic activity of streptococcus bovis jb1, prevotella albensis, and butyrivibrio fibrisolvens dsm3071. the growth of s. bovis and b. fibrisolvens was enhanced by nh(3) and aa, and that of p. albensis was reduced compared with a control with protein as the sole source of nitrogen. the proteolytic activity of s. bovis and p. albensis was reduced, but that of b. fibrisolven ...200010827280
development of a competitive polymerase chain reaction assay for the ruminal bacterium butyrivibrio fibrisolvens ob156 and its use for tracking an ob156-derived recombinant.a competitive polymerase chain reaction assay targeting the 16s rdna was developed for quantitating the rumen bacterium butyrivibrio fibrisolvens ob156. a competitor dna, serving as an internal control in the competitive polymerase chain reaction reaction, was constructed by polymerase chain reaction using a looped oligo longer than the normal primer. coamplification of the target dna with known amounts of the competitor dna allowed quantitation of the target dna in both pure culture and mixed c ...200010913703
effect of linoleic acid concentration on conjugated linoleic acid production by butyrivibrio fibrisolvens a38.butyrivibrio fibrisolvens a38 inocula were inhibited by as little as 15 microm linoleic acid (la), but growing cultures tolerated 10-fold more la before growth was inhibited. growing cultures did not produce significant amounts of cis-9, trans-11 conjugated linoleic acid (cla) until the la concentration was high enough to inhibit biohydrogenation, growth was inhibited, and lysis was enhanced. washed-cell suspensions that were incubated anaerobically with 350 microm la converted most of the la to ...200011097894
evidence for recent intergeneric transfer of a new tetracycline resistance gene, tet(w), isolated from butyrivibrio fibrisolvens, and the occurrence of tet(o) in ruminal bacteria.we have previously reported high-frequency transfer of tetracycline resistance between strains of the rumen anaerobic bacterium butyrivibrio fibrisolvens. donor strains were postulated to carry two tcr genes, one of which is transferred on a novel chromosomal element. it is shown here that coding sequences within the non-transmissible gene in b. fibrisolvens 1.230 are identical to those of the streptococcus pneumoniae tet(o) gene. this provides the first evidence for genetic exchange between fac ...199911207718
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.200111298234
phenotypic and genetic data supporting reclassification of butyrivibrio fibrisolvens isolates.among 55 butyrivibrio fibrisolvens strains five ribotypes of b. fibrisolvens were described on the basis of rflp profiles of 16s rdna regions obtained with restriction endonuclease haeiii. in the phylogenetic tree, these ribotypes were located in the xiva cluster of gram-positive bacteria. phenotypic differences of selected ribotype groups became the basis for further reclassification of b. fibrisolvens.200111501475
application of flow cytometry for ecological monitoring of the rumen microbial ecosystem.flow cytometry in combination with fluorescently labeled ribosomal rna oligonucleotide probes was used for enumeration and monitoring of ruminal bacteria. the polyanionic azo dye trypan blue was used for discrimination between live bacterial cells and inorganic particles and the separation was further improved by lysozyme treatment and sonication. cy3-labeled universally conserved probe eub338 and fitc-labeled prevotella bryantii specific probe pbb14 were used for in situ hybridization in mixed ...200111501477
reliable identification of prevotella and butyrivibrio spp. from rumen by fatty acid methyl ester profiles.data for bacterial identification were provided by culturing anaerobic bacteria under standardized conditions followed by extraction and methylation of cellular long-chain fatty acids and gas chromatographic analysis. the databases of fatty acid methyl ester (fames) profiles for two predominant ruminal genera, prevotella and butyrivibrio, were created. major long-chain cellular fatty acids found in the 23 analyzed prevotella strains were 15:0 (anteiso), 15:0, 15:0 (iso) and 16:0. the strains of ...200111501478
development of competitive pcr for detection of butyrivibrio fibrisolvens in the rumen.competitive pcr method was developed for the detection and enumeration of butyrivibrio fibrisolvens. sequences of 16s rdna were obtained from our isolates (serving as a source of data for primer design) and were distinguished into nine different groups of butyrivibria. specific primers for two distinct groups were designed with the help of bioedit program. these primers were tested with dna of 20 strains of ruminal b. fibrisolvens isolates. annealing temperature 58 degrees c showed a little spec ...200111501480
multiple endoxylanases of butyrivibrio sp.butyrivibrio sp. mz 5 with a high xylanolytic activity was isolated. four major xylanases were detected in the cell-associated fraction using the zymogram technique. the xylanolytic activity was inducible with the oat spelts xylan; two endoxylanases (51 and 145 kda) were formed constitutively. the bulk of the xylanolytic activity was cell-bound and growth-phase dependent; the maximum activity in the cell-associated fraction was achieved after 16 h of incubation. the highest xylanolytic activity ...200111501489
the effect of condensed tannins from lotus pedunculatus and lotus corniculatus on the growth of proteolytic rumen bacteria in vitro and their possible mode of action.five strains of proteolytic rumen bacteria were treated with condensed tannins (ct) purified from lotus pedunculatus and lotus corniculatus to investigate their effect on the growth of these bacteria in vitro. streptococcus bovis ncfb 2476, eubacterium sp. c124b, prevotella bryantii b14, butyrivibrio fibrisolvens h17c, and clostridium proteoclasticum b316t were tested against 200, 400, and 600 microg ct x ml(-1) extracted from l. pedunculatus and l. corniculatus. in the absence of ct, all bacter ...200111547882
novel tetracycline resistance gene, tet(32), in the clostridium-related human colonic anaerobe k10 and its transmission in vitro to the rumen anaerobe butyrivibrio fibrisolvens.a novel tetracycline resistance gene, designated tet(32), which confers a high level of tetracycline resistance, was identified in the clostridium-related human colonic anaerobe k10, which also carries tet(w). tet(32) was transmissible in vitro to the rumen anaerobe butyrivibrio fibrisolvens 2221(r). the predicted gene product of tet(32) has 76% amino acid identity with tet(o). pcr amplification indicated that tet(32) is widely distributed in the ovine rumen and in porcine feces.200111600392
Displaying items 101 - 200 of 333