Publications
| Title | Abstract | Year(sorted ascending) Filter | PMID Filter |
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| 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 ... | 1997 | 9143105 |
| 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 ... | 1997 | 9023916 |
| 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 ... | 1997 | 9023920 |
| 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 ... | 1997 | 9141683 |
| 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 ... | 1998 | 9483796 |
| 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 ... | 1998 | 9631539 |
| 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 |
| 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. | 1998 | 9726903 |
| 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 ... | 1999 | 10427063 |
| 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 ... | 1999 | 10382263 |
| 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 ... | 1999 | 10486059 |
| 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 ... | 1999 | 10568481 |
| 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 ... | 1999 | 11207718 |
| 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 ... | 1999 | 9871109 |
| 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 ... | 1999 | 10224011 |
| 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 ... | 2000 | 10679047 |
| 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. | 2000 | 10681357 |
| 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 ... | 2000 | 11097894 |
| 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 ... | 2000 | 10827280 |
| 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 ... | 2000 | 10913703 |
| 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. | 2001 | 11501475 |
| 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 ... | 2001 | 11501477 |
| 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. | 2001 | 11600392 |
| 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 |
| 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 ... | 2001 | 11501478 |
| 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 ... | 2001 | 11501480 |
| 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 ... | 2001 | 11501489 |
| 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 ... | 2001 | 11547882 |
| presence of butyrivibrio fibrisolvens in the digestive tract of dogs and cats, and its contribution to butyrate production. | numbers of butyrivibrio fibrisolvens, a major butyrate-producing bacterium in the rumen, in feces of dogs and cats were estimated by competitive pcr. the type iib of b. fibrisolvens, which produces much more lactate than butyrate, was detected at the levels (cells per g of feces dry weight) of 2.4x10(3)-9.0x10(5) for dogs and 1.7x10(4-)-6.2x10(5) for cats. however, the type i that produces much more butyrate than the type iib was not detected in cat or dog feces (less than 6.0x10(4) cells per g ... | 2001 | 12483606 |
| lotus corniculatus condensed tannins decrease in vivo populations of proteolytic bacteria and affect nitrogen metabolism in the rumen of sheep. | condensed tannins in forage legumes improve the nutrition of sheep by reducing ruminal degradation of plant protein and increasing crude protein flow to the intestine. however, the effects of condensed tannins in forage legumes on rumen bacterial populations in vivo are poorly understood. the aim of this study was to investigate the specific effects of condensed tannins from lotus corniculatus on four proteolytic rumen bacteria in sheep during and after transition from a ryegrass (lolium perenne ... | 2002 | 12489781 |
| the adaptation and resistance of clostridium aminophilum f to the butyrivibriocin-like substance of butyrivibrio fibrisolvens jl5 and monensin. | when the amino acid-fermenting bacterium clostridium aminophilum f was inoculated into media containing 1 microm monensin or a bacteriocin-like inhibitory substance (blis) from butyrivibrio fibrisolvens jl5, the cultures lagged and growth was not observed for more than 12 h. the monensin- and blis-treated cultures eventually grew rapidly and did not lag a second time. because cross-resistance could not be demonstrated, it appeared that the adaptation was specific. non-adapted cells that were inc ... | 2002 | 12007660 |
| effects of exogenous ammonia or free amino acids on proteolytic activity and protein breakdown products in streptococcus bovis, prevotella albensis, and butyrivibrio fibrisolvens. | we studied in details the ammonia or free amino acids (aa) effects on proteolytic activity of three ruminal bacteria: enzymatic activities and protein breakdown products were measured at the end of the exponential growth phase. in streptococcus bovis the simultaneous uptake of ammonia and probably small peptides induced a decline in total proteolytic activity as a result of changes in endopeptidasic activities. with free aa, the tendency for the endopeptidasic activities to specialise was more e ... | 2002 | 12000995 |
| widespread distribution of a tet w determinant among tetracycline-resistant isolates of the animal pathogen arcanobacterium pyogenes. | tetracycline resistance is common among isolates of the animal commensal and opportunistic pathogen arcanobacterium pyogenes. the tetracycline resistance determinant cloned from two bovine isolates of a. pyogenes was highly similar at the dna level (92% identity) to the tet(w) gene, encoding a ribosomal protection tetracycline resistance protein, from the rumen bacterium butyrivibrio fibrisolvens. the tet(w) gene was found in all 20 tetracycline-resistant isolates tested, indicating that it is a ... | 2002 | 11959557 |
| bacteriocin-like activity of butyrivibrio fibrisolvens jl5 and its effect on other ruminal bacteria and ammonia production. | when ruminal bacteria from a cow fed hay were serially diluted into an anaerobic medium that had only peptides and amino acids as energy sources, little growth or ammonia production was detected at dilutions greater than 10(-6). the 10(-8) and 10(-9) dilutions contained bacteria that fermented carbohydrates, and some of these bacteria inhibited clostridium sticklandii sr, an obligate amino acid-fermenting bacterium. phylogenetic analysis indicated that the most active isolate (jl5) was closely r ... | 2002 | 11872448 |
| 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 |
| [metabolism of rumen microbial populations formed on biosubstrates with different assimilation under the effect of pentachlorophenol]. | it has been established that metabolism of mixed microbial population formed on easy assimilated sources of energy and nitrogen (concentrate diet) progressed on higher level. there is increase of amilolytic activity, formation of lactate, ammonia, low molecular carbonic acids with predomination of propionate molar fraction. the increased resistance to effect of pentachlorophenol (pcp) is characteristic nature of the latter. the role of the most resistant synthrophic bacteria to pcp increases. th ... | 2002 | 12916235 |
| butyrivibriocin ar10, a new cyclic bacteriocin produced by the ruminal anaerobe butyrivibrio fibrisolvens ar10: characterization of the gene and peptide. | the gene (bvia) encoding the ruminal bacteriocin butyrivibriocin ar10 was cloned from an ecori library by using an oligonucleotide probe based on a partial peptide sequence of the previously isolated peptide. the gene encoded an 80 amino acid prebacteriocin that demonstrated significant identity with the cyclic bacteriocin gassericin a. negative ion time of flight mass spectroscopic analysis (esi/ms) indicated a mass of 5981.5 da for the isolated bacteriocin, a molecular mass that could not be g ... | 2003 | 15162201 |
| establishing populations of megasphaera elsdenii ye 34 and butyrivibrio fibrisolvens ye 44 in the rumen of cattle fed high grain diets. | to determine whether megasphaera elsdenii ye34 (lactic acid degrader) and butyrivibrio fibrisolvens ye44 (alternative starch utilizer to streptococcus bovis) establish viable populations in the rumen of beef cattle rapidly changed from a forage-based to a grain-based diet. | 2003 | 12911711 |
| possible quorum sensing in the rumen microbial community: detection of quorum-sensing signal molecules from rumen bacteria. | the bioluminescence assay using vibrio harveyi bb170 was used to examine quorum-sensing autoinducer 2 (ai-2) activity from cell-free culture fluids of rumen bacteria. the assay showed that the culture fluids of four species of rumen bacteria, butyrivibrio fibrisolvens, eubacterium ruminantium, ruminococcus flavefaciens, and succinimonas amylolytica, contained ai-2-like molecules. furthermore, homologues for luxs genes were detected in rumen fluids collected from three cows and in bacterial cells ... | 2003 | 12594022 |
| butyrivibrio hungatei sp. nov. and pseudobutyrivibrio xylanivorans sp. nov., butyrate-producing bacteria from the rumen. | two novel gram-negative, anaerobic, non-spore-forming, butyrate-producing bacterial species, strains mz 5t and jk 615t, were isolated from the rumen fluid of cow and sheep. both strains were curved rods that were motile by means of single polar or subpolar flagellum and common in the rumen microbial ecosystem. strain mz 5t produced high xylanase, proteinase, pectin hydrolase and dnase activities; 1,4-beta-endoglucanase was also detected in the culture medium. the bacterium utilized a wide range ... | 2003 | 12656174 |
| paex, a second pectin acetylesterase of erwinia chrysanthemi 3937. | erwinia chrysanthemi causes soft-rot diseases of various plants by enzymatic degradation of the pectin in plant cell walls. pectin is a complex polysaccharide. the main chain is constituted of galacturonate residues, and some of them are modified by methyl and/or acetyl esterification. esterases are necessary to remove these modifications and, thus, to facilitate the further degradation of the polysaccharidic chain. in addition to paey, the first pectin acetylesterase identified in the e. chrysa ... | 2003 | 12730169 |
| partial inhibition of biohydrogenation of linoleic acid can increase the conjugated linoleic acid production of butyrivibrio fibrisolvens a38. | butyrivibrio fibrisolvens a38, one of the most active rumen bacteria in conjugated linoleic acid (cla) production, was characterized in vitro. previous findings that some inhibitory levels of substrate for biohydrogenation (bh) by b. fibrisolvens a38 resulted in more cla accumulation led to a prediction that partial inhibition of bh could increase ruminal cla production. the inhibitory conditions for bacterial growth were less effective on the isomerization step than on the following reduction s ... | 2003 | 12848494 |
| structural studies of the extracellular polysaccharide produced by butyrivibrio fibrisolvens strain h10b. | the extracellular polysaccharide produced by butyrivibrio fibrisolvens strain h10b, when grown under strictly anaerobic conditions with glucose as carbohydrate source, has been studied by chemical and spectroscopic techniques. the results demonstrate that the polysaccharide consists of hexasaccharide repeating units with the following structure: [structure: see text] the isolated polysaccharide was found to be approximately 65% acetylated at o-2 of the 3-o-[(s)-1-carboxyethyl]-beta-d-glcp residu ... | 2003 | 12860428 |
| characterization and transcription of the genes encoding enzymes involved in butyrate production in butyrivibrio fibrisolvens. | genes encoding enzymes that catalyze butyryl-coa formation from acetyl-coa in a type ii strain of butyrivibrio fibrisolvens were analyzed. the genes encoding thiolase, beta-hydroxybutyryl-coa dehydrogenase, butyryl-coa dehydrogenase, and electron transfer flavoproteins were clustered, but the crotonase gene was not present in this region. the deduced amino acid sequences of these enzymes were similar to those of clostridia. the clustered genes were shown to be cotranscribed. the rate of butyrate ... | 2003 | 14570270 |
| biohydrogenation of c18 unsaturated fatty acids to stearic acid by a strain of butyrivibrio hungatei from the bovine rumen. | to identify a ruminal isolate which transforms oleic, linoleic and linolenic acids to stearic acid and to identify transient intermediates formed during biohydrogenation. | 2003 | 14633116 |
| phylogenetic analysis of fiber-associated rumen bacterial community and pcr detection of uncultured bacteria. | the fiber-associated rumen bacterial community was phylogenetically examined by analysis of 16s rrna gene (16s rdna) sequences. hay stems of orchardgrass and alfalfa were incubated for 6 and 20 h, respectively in the rumen of two different sheep, and total dna was extracted from the incubated stems to clone bacterial 16s rdnas using polymerase chain reaction (pcr). of 91 such clones, 21 showed more than 97% sequence similarity with known isolates, 32 clones had 90-97% similarity with known seque ... | 2003 | 14659538 |
| expression and export of a ruminococcus albus cellulase in butyrivibrio fibrisolvens through the use of an alternative gene promoter and signal sequence. | ruminococcal cellulase (ruminococcus albus f-40 endoglucanase egi) was successfully expressed in butyrivibrio fibrisolvens ob156c, using the erm promoter from pambeta1. a newly identified signal peptide coding region of xyna from b. fibrisolvens 49 allowed efficient translocation of the foreign egi into the extracellular fraction. first, b. fibrisolvens xyna with or without its own putative signal peptide (xyna sp) coding region was cloned into a shuttle vector to transform b. fibrisolvens ob156 ... | 2003 | 14569291 |
| the butyrivibrio fibrisolvens tet(w) gene is carried on the novel conjugative transposon tnb1230, which contains duplicated nitroreductase coding sequences. | the butyrivibrio fibrisolvens tet(w) gene is located on the conjugative transposon tnb1230. tnb1230 encodes transfer proteins with 48 to 67% identity to some of those encoded by tn1549. tet(w) is flanked by directly repeated sequences with significant homology to oxygen-insensitive nitroreductases. the 340 nucleotides upstream of tet(w) are strongly conserved and are required for tetracycline resistance. | 2004 | 15150255 |
| use of community genome arrays (cgas) to assess the effects of acacia angustissima on rumen ecology. | this research developed a community genome array (cga) to assess the effects of acacia angustissima on rumen microbiology. a. angustissima produces non-protein amino acids as well as tannins, which may be toxic to animals, and cga was used to assess the effects of this plant on the ecology of the rumen. cgas were developed using a 7.5 cmx2.5 cm nylon membrane format that included up to 96 bacterial genomes. it was possible to separately hybridize large numbers of membranes at once using this min ... | 2004 | 15347749 |
| variation in antimicrobial action of proanthocyanidins from dorycnium rectum against rumen bacteria. | the proanthocyanidin polymer fractions of the leaves of the forage legume dorycnium rectum were analysed by acid catalysis with benzyl mercaptan, nmr and es-ms. the results showed that d. rectum differs from other temperate proanthocyanidin-containing forage legumes in that the range of polymers extends up to very high degrees of polymerisation. three fractions were characterised as low, medium, and high molecular weight proanthocyanidin fractions with mean degree of polymerisations of 10.3, 41 ... | 2004 | 15381413 |
| the use of pcr for the identification and characterisation of bacteriocin genes from bacterial strains isolated from rumen or caecal contents of cattle and sheep. | pcr primers were designed to amplify the gene that encodes bovicin 255 from streptococcus gallolyticus lrc0255 and the bacteriocin genes from butyrivibrio fibrisolvens strains ar10 and or79a (bvid and bvi79a) in order to screen for their incidence in rumen and caecal b. fibrisolvens and streptococcus bovis-like isolates from new zealand and north american ruminants. none of the b. fibrisolvens-like strains (n=34) isolated from new zealand or north america had the genes encoding for butyrivibrioc ... | 2004 | 19712403 |
| genetic diversity of viable, injured, and dead fecal bacteria assessed by fluorescence-activated cell sorting and 16s rrna gene analysis. | a novel approach combining a flow cytometric in situ viability assay with 16s rrna gene analysis was used to study the relationship between diversity and activity of the fecal microbiota. simultaneous staining with propidium iodide (pi) and syto bc provided clear discrimination between intact cells (49%), injured or damaged cells (19%), and dead cells (32%). the three subpopulations were sorted and characterized by denaturing gradient gel electrophoresis (dgge) of 16s rrna gene amplicons obtaine ... | 2005 | 16085863 |
| oral administration of butyrivibrio fibrisolvens, a butyrate-producing bacterium, decreases the formation of aberrant crypt foci in the colon and rectum of mice. | butyrivibrio fibrisolvens, a butyrate-producing ruminal bacterium, was evaluated for use as a probiotic to prevent colorectal cancer. oral administration to jcl:icr mice of a new strain of b. fibrisolvens (mdt-1) that produces butyrate at a high rate (10(9) cfu/dose) increased the rate of butyrate production by fecal microbes, suggesting that mdt-1 can grow in the gut. the number of colorectal aberrant crypt foci (acf), putative preneoplastic lesions induced by 1,2-dimethylhydrazine, was reduced ... | 2005 | 16317136 |
| effect of the microbial feed additive saccharomyces cerevisiae cncm i-1077 on protein and peptide degrading activities of rumen bacteria grown in vitro. | we investigated the potential of the ruminant feed additive saccharomyces cerevisiae cncm i-1077 on protein and peptide degrading activities of the rumen bacterial species prevotella albensis m384, streptococcus bovis 20480, and butyrivibrio fibrisolvens 3071 grown in vitro. alive or heat-killed yeast cells were added to bacterial cultures in a complex casein-glucose medium. after incubation of the cultures at 39 degrees c under o(2)-free co(2), peptidase activities were determined in the absenc ... | 2005 | 15702254 |
| occurrence of restriction-modification systems in ruminal butyrate-producing bacteria. | thirty-five strains of ruminal bacteria belonging to the former butyrivibrio fibrisolvens species were screened for the presence of site-specific restriction endonuclease and modification methyltransferase activities. seven strains possessed endonuclease activities detectable in crude cell extracts. the recognition sequences and optimal reaction conditions for seven of them were determined. five enzymes were found to be isoschizomers of type ii endonucleases (ecorv, nsii, asei (2x) and saui), on ... | 2005 | 16701584 |
| a new strain of butyrivibrio fibrisolvens that has high ability to isomerize linoleic acid to conjugated linoleic acid. | a new strain of butyrivibrio fibrisolvens (th1) that has high potential to produce conjugated linoleic acid (cla) was isolated. strain th1 had higher la isomerase (la-i) activity, and was much more tolerant to linoleic acid (la) than other strains examined. however, high cla reductase (cla-r) activity resulted in the temporary accumulation of cla and subsequent conversion to trans-vaccenic acid (t-va). when la was added to growing th1 cultures in a solution with dimethylsulfoxide (la/dmso), cla ... | 2005 | 15942871 |
| characterization and transcription of the genes involved in butyrate production in butyrivibrio fibrisolvens type i and ii strains. | the genes in butyrivibrio fibrisolvens that encode the enzymes involved in butyrate production were sequenced. in a type i strain (atcc 19171(t)), the genes coding for the enzymes that catalyze the conversion from acetyl-coa to butyryl-coa, thl (thiolase), crt (crotonase), hbd (beta-hydroxybutyryl-coa dehydrogenase), bcd (butyryl-coa dehydrogenase), etfb (electron transfer flavoprotein [etf]-beta), and etfa (etf-alpha), were found to be clustered and arranged in this order. a type ii strain (atc ... | 2005 | 15991056 |
| horizontal transfer of erythromycin resistance from clostridium difficile to butyrivibrio fibrisolvens. | this study demonstrates for the first time the in vitro transfer of the erythromycin resistance gene erm(b) between two obligate anaerobes, the human spore-forming pathogen clostridium difficile and the rumen commensal butyrivibrio fibrisolvens, suggesting that this event might occur also in the natural environment. | 2005 | 16304188 |
| isolation of a novel strain of butyrivibrio fibrisolvens that isomerizes linoleic acid to conjugated linoleic acid without hydrogenation, and its utilization as a probiotic for animals. | isolation of a new strain of butyrivibrio fibrisolvens possessing great capacity to produce conjugated linoleic acid (cla) in order to utilize as a probiotic for animals. | 2006 | 16553734 |
| augmentation of vaccenate production and suppression of vaccenate biohydrogenation in cultures of mixed ruminal microbes. | to increase ruminal outflow of trans-vaccenic acid (t-va), a new strain of butyrivibrio fibrisolvens (mdt-10) was isolated that has a great ability to hydrogenate linoleic acid (la) to t-va. when strain mdt-10 was added to the batch cultures of mixed ruminal microbes (1% of the total number of viable ruminal bacteria), la conversion to t-va increased greatly; after 3 h, t-va levels were > 4-fold higher than the control. by 10 h, all of the t-va was hydrogenated to stearic acid. however, when a n ... | 2006 | 16507700 |
| assessment of biases associated with profiling simple, model communities using terminal-restriction fragment length polymorphism-based analyses. | community profiles based on terminal-restriction fragment length polymorphism (t-rflp) analyses of amplified ribosomal rna genes are used to monitor changes in microbial community structure and are sometimes employed for semi-quantitative estimates of species richness and abundance in environmental samples. to assess the accuracy of t-rflp community profiles representing the relative abundance of bacteria in a sample, five species of ruminal bacteria were used to construct simple "communities". ... | 2006 | 16563536 |
| the effect of polysaccharide-degrading wine yeast transformants on the efficiency of wine processing and wine flavour. | commercial polysaccharase preparations are applied to winemaking to improve wine processing and quality. expression of polysaccharase-encoding genes in saccharomyces cerevisiae allows for the recombinant strains to degrade polysaccharides that traditional commercial yeast strains cannot. in this study, we constructed recombinant wine yeast strains that were able to degrade the problem-causing grape polysaccharides, glucan and xylan, by separately integrating the trichoderma reesei xyn2 xylanase ... | 2006 | 16644051 |
| antimicrobial susceptibility of bifidobacterium strains from humans, animals and probiotic products. | the aim of this study was to assess the antimicrobial susceptibility of a taxonomically diverse set of bifidobacterium strains to different classes of antimicrobial agents using a recently described medium. | 2006 | 16698847 |
| extracellular metabolomics: a metabolic footprinting approach to assess fiber degradation in complex media. | this work reports the implementation and optimization of a method for high-throughput analysis of metabolites produced by the breakdown of natural polysaccharides by microorganisms. our simple protocol enables simultaneous separation and quantification of more than 40 different sugars and sugar derivatives, in addition to several organic acids in complex media, using 50-mul samples and a standard gas chromatography-mass spectrometry platform that was fully optimized for this purpose. as an imple ... | 2006 | 16356465 |
| effect of oral administration of butyrivibrio fibrisolvens mdt-1 on experimental enterocolitis in mice. | butyrivibrio fibrisolvens mdt-1, a butyrate-producing strain, was evaluated for use as a probiotic to prevent enterocolitis. oral administration of the mdt-1 strain (10(9) cfu/dose) alleviated the symptoms of colitis (including body weight loss, diarrhea, bloody stool, organic disorder, and mucosal damage) that are induced in mice drinking water that contains 3.0% dextran sulfate sodium. in addition, myeloperoxidase (mpo) activity levels in colonic tissue were reduced, suggesting that mdt-1 miti ... | 2006 | 16988006 |
| influence of fish oil on ruminal biohydrogenation of c18 unsaturated fatty acids. | dietary cis-9, trans-11-conjugated linoleic acid (cla) is generally thought to be beneficial for human health. fish oil added to ruminant diets increases the cla concentration of milk and meat, an increase thought to arise from alterations in ruminal biohydrogenation of unsaturated fatty acids. to investigate the mechanism for this effect, in vitro incubations were carried out with ruminal digesta and the main biohydrogenating ruminal bacterium, butyrivibrio fibrisolvens. linoleic acid (la) or a ... | 2006 | 16768845 |
| comparative analysis of sequences flanking tet(w) resistance genes in multiple species of gut bacteria. | tet(w) is one of the most abundant tetracycline resistance genes found in bacteria from the mammalian gut and was first identified in the rumen anaerobe butyrivibrio fibrisolvens 1.230, where it is highly mobile and its transfer is associated with the transposable chromosomal element tnb1230. in order to compare the genetic basis for tet(w) carriage in different bacteria, we studied sequences flanking tet(w) in representatives of seven bacterial genera originating in diverse gut environments. th ... | 2006 | 16870752 |
| increased expression of a molecular chaperone groel in response to unsaturated fatty acids by the biohydrogenating ruminal bacterium, butyrivibrio fibrisolvens. | butyrivibrio fibrisolvens is the most active bacterial species in the biohydrogenation of polyunsaturated fatty acids (pufa) in the rumen. it needs to remove the unsaturated bonds in order to detoxify the pufa to enable the growth of the bacterium. here, we investigated the response of cell membrane-associated proteins in b. fibrisolvens to growth in the presence of pufa. numerous changes were observed in the cell membrane-associated proteome. one of the main modifications occurring when the 18: ... | 2006 | 16923082 |
| molecular analysis of tet(w) gene-mediated tetracycline resistance in dominant intestinal bifidobacterium species from healthy humans. | tet(w) was found responsible for tetracycline resistance (mics, 4 to > or =32 microg ml(-1)) in dominant bifidobacterial species from the gastrointestinal tracts of healthy humans. the gene from bifidobacterium longum h66 proved to be identical over a 2.6-kbp region to the recently described tet(w) determinant of butyrivibrio fibrisolvens. | 2006 | 16936047 |
| diet-dependent shifts in ruminal butyrate-producing bacteria. | the influence of a host's diet on butyrivibrio and pseudobutyrivibrio populations was investigated by competitive pcr. specific primers were designed and competitive pcrs developed for both groups. results (from 4 cows with different diets) suggested that high-fiber intake essentially increases the butyrivibrio amounts in the rumen, whereas high-energy food additives lead to its suppression. the pseudobutyrivibrio concentration also changed during the experiment but without any significant relat ... | 2006 | 17007429 |
| cell-associated alpha-amylases of butyrate-producing firmicute bacteria from the human colon. | selected butyrate-producing bacteria from the human colon that are related to roseburia spp. and butyrivibrio fibrisolvens showed a good ability to utilize a variety of starches for growth when compared with the gram-negative amylolytic anaerobe bacteroides thetaiotaomicron. a major cell-associated amylase of high molecular mass (140-210 kda) was detected in each strain by sds-page zymogram analysis, and genes corresponding to these enzymes were analysed for two representative strains. amy13b fr ... | 2006 | 17074899 |
| [inhibition of carbohydrate metabilsm enzymes by pentachlorophenol in cells of pectinolytic bacteria from gastrointestinal tract of animals and effect of clinoptilolite adsorbents on this process]. | changes in functional activity of specific enzyme reactions in the cells of pectinolytic bacteria from the gastrointestinal tract of animals in vitro cultivated in the medium containing pectin or glucose were studied against a background of the low dose effect of the wide spread biocide pentachlorophenol alone as well as in combination with the natural sorbents clinoptilolites. regardless of the absence of transketolase reaction in the cells of all studied strains, they metabolized highly the ab ... | 2006 | 17290794 |
| clostridium proteoclasticum: a ruminal bacterium that forms stearic acid from linoleic acid. | the aim of this study was to identify ruminal bacteria that form stearic acid (18 : 0) from linoleic acid (cis-9,cis-12-18 : 2). one 18 : 0-producing isolate, p-18, isolated from the sheep rumen was similar in morphology and metabolic properties to 'fusocillus' spp. isolated many years ago. phylogenetic analysis based on nearly full-length 16s rrna gene sequence (>1300 bp) analysis indicated that the stearate producer was most closely related to clostridium proteoclasticum b316(t). clostridium p ... | 2006 | 17147764 |
| dominance of prevotella and low abundance of classical ruminal bacterial species in the bovine rumen revealed by relative quantification real-time pcr. | relative quantification real-time pcr was used to quantify several bacterial species in ruminal samples from two lactating cows, each sampled 3 h after feeding on two successive days. abundance of each target taxon was calculated as a fraction of the total 16s rrna gene copies in the samples, using taxon-specific and eubacterial domain-level primers. bacterial populations showed a clear predominance of members of the genus prevotella, which comprised 42% to 60% of the bacterial rrna gene copies ... | 2007 | 17235560 |
| novel rumen bacterial diversity in two geographically separated sub-species of reindeer. | svalbard reindeer (rangifer tarandus platyrhynchus) live under austere nutritional conditions on the high-arctic archipelago of svalbard, while semi-domesticated norwegian reindeer (r. tarandus tarandus) migrate between lush coastal summer pastures and inland winter pastures with lichens on mainland norway. svalbard reindeer are known to have high rumen concentrations of cellulolytic bacteria, ranging from 15% of the viable population in summer to 35% in winter, compared to only 2.5% in norwegia ... | 2007 | 17473904 |
| isomers of conjugated linoleic acids are synthesized via different mechanisms in ruminal digesta and bacteria. | digesta samples from the ovine rumen and pure ruminal bacteria were incubated with linoleic acid (la) in deuterium oxide-containing buffer to investigate the mechanisms of the formation of conjugated linoleic acids (clas). rumenic acid (ra; cis-9,trans-11-18:2), trans-9,trans-11-18:2, and trans-10,cis-12-18:2 were the major cla intermediates formed from la in ruminal digesta, with traces of trans-9,cis-11-18:2, cis-9,cis-11-18:2, and cis-10,cis-12-18:2. mass spectrometry indicated an increase in ... | 2007 | 17644775 |
| purification and gene sequencing of conjugated linoleic acid reductase from a gastrointestinal bacterium, butyrivibrio fibrisolvens. | to characterize the cause for the lack of conjugated linoleic acid (cla) reductase (cla-r) activity in the butyrivibrio fibrisolvens mdt-5 strain that rapidly isomerizes linoleic acid (la) to cla without hydrogenation, the cla-r was purified and its gene (cla-r) sequence was determined. | 2007 | 17650196 |
| isolation and characterization of putative pseudobutyrivibrio ruminis promoters. | novel plasmids were constructed for the analysis of dna fragments from the rumen bacterium pseudobutyrivibrio ruminis. five previously unidentified promoters were characterized using a novel primer extension method to identify transcription start sites. the genes downstream of these promoters were not identified, and their activity in expression of genomic traits in wild-type p. ruminis remains putative. comparison with promoters from this and closely related species revealed a consensus sequenc ... | 2007 | 17768250 |
| effect of oral administration of butyrivibrio fibrisolvens mdt-1, a gastrointestinal bacterium, on 3-methylcholanthrene-induced tumor in mice. | butyrivibrio fibrisolvens mdt-1 was evaluated for use as a probiotic to prevent tumor formation. oral administration of mdt-1 (10(9) cfu/dose, 3 times a wk for 15 wk) delayed the onset of tumors induced by 3-methylcholanthrene and also reduced tumor incidence in mice. furthermore, the numbers of natural killer (nk) and nkt cells in the spleen increased markedly in response to mdt-1 administration. increased numbers of nk and nkt cells may contribute to the alleviation of carcinogenesis by mdt-1 ... | 2007 | 17927507 |
| the heterologous expression of polysaccharidase-encoding genes with oenological relevance in saccharomyces cerevisiae. | the main objective of this study was to develop polysaccharide-degrading wine strains of saccharomyces cerevisiae, which are able to improve aspects of wine processing and clarification, as well as colour extraction and stabilization during winemaking. | 2007 | 18045408 |
| adaptation of adhesion test using caco-2 cells for anaerobic bacterium pseudobutyrivibrio xylanivorans, a probiotic candidate. | pseudobutyrivibrio xylanivorans strain mz5(t), an anaerobic bacterium (originating from the rumen of a holstein-friesian cow), has some attributes that make it a possible probiotic strain (very active hydrolases, bacteriocin and conjugated linoleic acid production). for the estimation of its adhesion ability, the adhesion test on caco-2 cells was introduced and adapted. the adhesion was performed in an anaerobic glove box in standard 24-well plates at neutral ph for 30 min. the best method for s ... | 2007 | 18062185 |
| relation between phylogenetic position, lipid metabolism and butyrate production by different butyrivibrio-like bacteria from the rumen. | the butyrivibrio group comprises butyrivibrio fibrisolvens and related gram-positive bacteria isolated mainly from the rumen of cattle and sheep. the aim of this study was to investigate phenotypic characteristics that discriminate between different phylotypes. the phylogenetic position, derived from 16s rdna sequence data, of 45 isolates from different species and different countries was compared with their fermentation products, mechanism of butyrate formation, lipid metabolism and sensitivity ... | 2007 | 17077990 |
| expression of a beta-glucosidase gene results in increased accumulation of salicylic acid in transgenic nicotiana tabacum cv. xanthi-nc nn genotype. | a beta-glucosidase gene (bgla) from butyrivibrio fibrisolvens h17c was cloned into the binary vector pga482 under the control of the 35s cauliflower mosaic virus (camv) promoter. a second construct was generated for accumulation of the bgla gene product in the vacuole of transformed tobacco plants. reverse transcription-polymerase chain reaction analysis demonstrated that the bgla gene was expressed in 71% of cytosol-targeted and 67% of vacuole-targeted transgenic tobacco t(1) plants. t(1) trans ... | 2007 | 17082925 |
| quantification of ruminal clostridium proteoclasticum by real-time pcr using a molecular beacon approach. | all members of the ruminal butyrivibrio group convert linoleic acid (cis-9,cis-12-18:2) via conjugated 18:2 metabolites (mainly cis-9,trans-11-18:2, conjugated linoleic acid) to vaccenic acid (trans-11-18:1), but only members of a small branch, which includes clostridium proteoclasticum, of this heterogeneous group further reduce vaccenic acid to stearic acid (18:0, sa). the aims of this study were to develop a real-time polymerase chain reaction (pcr) assay that would detect and quantify these ... | 2007 | 17897229 |
| metabolism of polyunsaturated fatty acids and their toxicity to the microflora of the rumen. | ruminal microorganisms hydrogenate polyunsaturated fatty acids (pufa) present in forages and thereby restrict the availability of health-promoting pufa in meat and milk. the aim of this study was to investigate pufa metabolism and the influence of pufa on members of the ruminal microflora. eleven of 26 predominant species of ruminal bacteria metabolised linoleic acid (la; cis-9,cis-12-18:2) substantially. the most common product was vaccenic acid (trans-11-18:1), produced by species related to b ... | 2007 | 17072533 |
| the characterization of lactic acid producing bacteria from the rumen of dairy cattle grazing on improved pasture supplemented with wheat and barley grain. | to identify and characterize the major lactic acid bacteria in the rumen of dairy cattle grazing improved pasture of rye grass and white clover and receiving a maize silage and grain supplement with and without virginiamycin. | 2008 | 18217928 |
| a new growth medium for rapid selection and purification of clostridium proteoclasticum transposon mutants. | clostridium proteoclasticum is commonly associated with the rumen microflora of pasture-fed cattle and sheep and has significant hemicellulose degradation abilities. genes involved in plant fibre breakdown are commonly identified by producing site-specific mutations. however, the genetics of c. proteoclasticum and other closely-related butyrivibrio/pseudobutyrivibrio species is not well-established. therefore random transposon mutants of c. proteoclasticum were generated by conjugation with ente ... | 2008 | 18346802 |
| diversity of the resident microbiota in a thermophilic municipal biogas plant. | biogas plants continuously convert biological wastes mainly into a mixture of methane, co2 and h2o-a conversion that is carried out by a consortium of bacteria and archaea. especially in the municipal plants dedicated towards waste treatment, the reactor feed may vary considerably, exposing the resident microbiota to a changing variety of substrates. to evaluate how and if such changes influence the microbiology, an established biogas plant (6,600 m3, up to 600 m3 biogas per h) was followed over ... | 2008 | 18820906 |
| genetic features of circular bacteriocins produced by gram-positive bacteria. | this review highlights the main genetic features of circular bacteriocins, which require the co-ordinated expression of several genetic determinants. in general terms, it has been demonstrated that the expression of such structural genes must be combined with the activity of proteins involved in maturation (cleavage/circularization) and secretion outside the cell via different transporter systems, as well as multifaceted immunity mechanisms essential to ensuring the bacteria's self-protection ag ... | 2008 | 18034824 |
| effect of monensin feeding and withdrawal on populations of individual bacterial species in the rumen of lactating dairy cows fed high-starch rations. | real-time polymerase chain reaction (pcr) was used to quantify 16 procaryotic taxa in the rumina of two lactating dairy cows following supply and subsequent withdrawal of the feed additive monensin (13.9 mg/kg of diet dry matter) in a high-starch, silage-based ration. pcr was conducted on dna from rumen samples collected 6 h post feeding on two successive days before monensin supplementation, after 30 days of monensin supplementation, and at six weekly intervals after monensin withdrawal. mean v ... | 2008 | 18535825 |
| biochemistry of pufa double bond isomerases producing conjugated linoleic acid. | the biotransformation of linoleic acid (la) into conjugated linoleic acid (cla) by microorganisms is a potentially useful industrial process. in most cases, however, the identities of proteins involved and the details of enzymatic activity regulation are far from clear. here we summarize available data on the reaction mechanisms of cla-producing enzymes characterized until now, from butyrivibrio fibrisolvens, lactobacillus acidophilus, ptilota filicina, and propionibacterium acnes. a general fea ... | 2008 | 18655062 |
| degradation of forage chicory by ruminal fibrolytic bacteria. | determine the susceptibility of forage chicory (cichorium intybus l.) to degradation by ruminal fibrolytic bacteria and measure the effects on cell-wall pectic polysaccharides. | 2008 | 18713292 |
| reclassification of clostridium proteoclasticum as butyrivibrio proteoclasticus comb. nov., a butyrate-producing ruminal bacterium. | it is proposed that clostridium proteoclasticum be reclassified as butyrivibrio proteoclasticus comb. nov. on the basis of phylogenetic position, dna g+c content and physiological traits. phylogenetic analyses based on 16s rrna gene sequences from an extensive range of taxa within clostridial rrna subcluster xiva grouped c. proteoclasticum together with isolates of the genus butyrivibrio, though this species was genetically distinct from the extant butyrivibrio species examined. the dna g+c cont ... | 2008 | 18768601 |
| accumulation of trans c18:1 fatty acids in the rumen after dietary algal supplementation is associated with changes in the butyrivibrio community. | optimization of the fatty acid composition of ruminant milk and meat is desirable. dietary supplementation of algae was previously shown to inhibit rumen biohydrogenation, resulting in an altered milk fatty acid profile. bacteria involved in biohydrogenation belong to the butyrivibrio group. this study was aimed at relating accumulation of biohydrogenation intermediates with shifts in butyrivibrio spp. in the rumen of dairy cows. therefore, an experiment was performed with three rumen-fistulated ... | 2008 | 18820074 |
| characterization of tet(32) genes from the oral metagenome. | tet(32) was identified in three bacterial isolates and in metagenomic dna from the human oral cavity. the regions immediately flanking the gene were found to have similarities to the mobile elements tnb1230 from butyrivibrio fibrisolvens, ate-3 from arcanobacterium pyogenes, and ctn5 from clostridium difficile. | 2009 | 18955517 |
| sucrose phosphorylase of the rumen bacterium pseudobutyrivibrio ruminis strain a. | to verify the taxonomic affiliation of bacterium butyrivibrio fibrisolvens strain a from our collection and to characterize its enzyme(s) responsible for digestion of sucrose. | 2009 | 19320946 |
| biotransformation of 2,4,6-trinitrotoluene by pure culture ruminal bacteria. | twenty-one ruminal bacteria species were tested for their ability to degrade 2,4,6-trinitrotoluene (tnt) within 24 h. butyrivibrio fibrisolvens, fibrobacter succinogenes, lactobacillus vitulinus, selenomonas ruminantium, streptococcus caprinus, and succinivibrio dextrinosolvens were able to completely degrade 100 mg/l tnt, with <5% of the original tnt recovered as diaminonitrotoluene metabolites. eubacterium ruminantium, lactobacillus ruminis, ruminobacter amylophilus, streptococcus bovis, and w ... | 2009 | 18839246 |
| effect of ph and level of concentrate in the diet on the production of biohydrogenation intermediates in a dual-flow continuous culture. | milk fat depression in cows fed high-grain diets has been related to an increase in the concentration of trans-10 c(18:1) and trans-10,cis-12 conjugated linoleic acid (cla) in milk. these fatty acids (fa) are produced as a result of the alteration in rumen biohydrogenation of dietary unsaturated fa. because a reduction in ruminal ph is usually observed when high-concentrate diets are fed, the main cause that determines the alteration in the biohydrogenation pathways is not clear. the effect of p ... | 2009 | 19700707 |
| mechanism of conjugated linoleic acid and vaccenic acid formation in human faecal suspensions and pure cultures of intestinal bacteria. | faecal bacteria from four human donors and six species of human intestinal bacteria known to metabolize linoleic acid (la) were incubated with la in deuterium oxide-enriched medium to investigate the mechanisms of conjugated linoleic acid (cla) and vaccenic acid (va) formation. the main cla products in faecal suspensions, rumenic acid (cis-9,trans-11-cla; ra) and trans-9,trans-11-cla, were labelled at c-13, as were other 9,11 geometric isomers. traces of trans-10,cis-12-cla formed were labelled ... | 2009 | 19118369 |
| evaluation and characterization of bacterial metabolic dynamics with a novel profiling technique, real-time metabolotyping. | environmental processes in ecosystems are dynamically altered by several metabolic responses in microorganisms, including intracellular sensing and pumping, battle for survival, and supply of or competition for nutrients. notably, intestinal bacteria maintain homeostatic balance in mammals via multiple dynamic biochemical reactions to produce several metabolites from undigested food, and those metabolites exert various effects on mammalian cells in a time-dependent manner. we have established a ... | 2009 | 19287504 |