Publications
| Title | Abstract | Year(sorted descending) Filter | PMID Filter |
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| in situ identification of carboxymethyl cellulose-digesting bacteria in the rumen of cattle fed alfalfa or triticale. | a method was developed and used to arrest and stain reducing sugars (glucose) produced by bacteria with cell-surface-associated carboxymethyl cellulase (cmcase) and endoglucanase activities (cmc bacteria) in the rumen of cows fed alfalfa or triticale. precipitation of silver oxide on the surface of individual cells was observed using cellulolytic bacterial pure cultures with known cmcase activity and rumen mixed cultures. the cmc bacteria in the liquid and solid fractions of the rumen digesta we ... | 2012 | 22224860 |
| effect of incremental levels of fish oil supplementation on specific bacterial populations in bovine ruminal fluid. | the objective of this study was to determine the effects of incremental replacement of dietary linoleic acid by >20-carbon polyunsaturated fatty acids (pufa) on changes in population of ruminal micro-organisms associated with fibre digestion and biohydrogenation using real-time pcr of bacterial 16s rrna sequences. four beef steers with ruminal cannulas were randomly assigned to control (ck, 65:35 forage to concentrate), ck with 3% sunflower oil plus 1% fish oil (s3f1), 2.5% sunflower oil plus 1. ... | 2011 | 21198963 |
| transposition of tn916 in the four replicons of the butyrivibrio proteoclasticus b316(t) genome. | the rumen bacterium butyrivibrio proteoclasticus b316(t) has a 4.4-mb genome composed of four replicons (approximately 3.55 mb, 361, 302 and 186 kb). mutagenesis of b316(t) was performed with the broad host-range conjugative transposon tn916 to screen for functionally important characteristics. the insertion sites of 123 mutants containing a single copy of tn916 were identified and corresponded to 53 different insertion points, of which 18 (34.0%), representing 39 mutants (31.7%), were in orfs a ... | 2011 | 21204937 |
| as yet uncultured bacteria phylogenetically classified as prevotella, lachnospiraceae incertae sedis and unclassified bacteroidales, clostridiales and ruminococcaceae may play a predominant role in ruminal biohydrogenation. | microbial biohydrogenation of dietary poly-unsaturated fatty acids (pufa) to saturated fatty acids (sfa) in the rumen results in the high ratio of sfa/pufa in ruminant products, such as meat and milk. in vitro, butyrivibrio proteoclasticus-related bacteria extensively biohydrogenate pufa to sfa, yet their contribution in the rumen has not been confirmed. the aim of this study was to evaluate the role of butyrivibrio proteoclasticus group bacteria in ruminal biohydrogenation and to assess the pos ... | 2011 | 21418494 |
| strategy of controlling the volumetric loading rate to promote hydrogen-production performance in a mesophilic-kitchen-waste fermentor and the microbial ecology analyses. | the kitchen waste was chosen as a high solid (42gl(-1) of volatile suspended solid, vss) and high organic (107gl(-1) of chemical oxygen demand) feedstock for operating a 3-l mesophilic fermentor. the greatest specific hydrogen production rate ( [formula: see text] ) was observed in stage 3 as 3.4l-h(2)l(-1)day(-1) with a volumetric loading rate (vlr) of 100g-codl(-1)day(-1); the highest hydrogen yield was observed in stage 2 as 96ml-h(2)g(-1) of influent vss with a vlr of 46g-codl(-1)day(-1). in ... | 2011 | 21421306 |
| the effect of lipid supplements on ruminal bacteria in continuous culture fermenters varies with the fatty acid composition. | a single flow continuous culture fermenter system was used in this study to investigate the influence of dietary lipid supplements varying in their fatty acid content on the dna concentration of selected rumen bacteria. four continuous culture fermenters were used in a 4×4 latin square design with four periods of 10 d each. treatment diets were fed at 45 g/d (dm basis) in three equal portions during the day. the diets were: 1) control (con), 2) control with animal fat source (sat), 3) control wi ... | 2011 | 21538241 |
| molecular diversity of bacteria in yunnan yellow cattle (bos taurs) from nujiang region, china. | the rumen content of four yunnan yellow cattle (bos taurs) were collected to determine the bacteria diversity by using 16s rrna gene sequence analysis. a total of 129 sequences were examined and the sequences were referred as 107 otu (operational taxonomy unit) according to the similarity level of 97% in gene sequence. similarity analysis revealed that yunnan yellow cattle had 12 sequences (10 otu) shared 97% or greater similarity with cultured rumen bacteria butyrivibrio fibrisolvens, succinicl ... | 2011 | 21598111 |
| effect of ruminal pulse dose of polyunsaturated fatty acids on ruminal microbial populations and duodenal flow and milk profiles of fatty acids. | the objective of this study was to examine the effect of ruminal pulse dose of free linoleic acid (la) and free docosahexaenoic acid (dha) on microbial populations in the rumen, duodenal fatty acid (fa) flow, milk composition, and milk fa profiles of chinese holstein dairy cows. four rumen- and duodenal-fistulated chinese holstein cows in mid lactation (138.5±10d in milk) were randomly assigned to 3 treatment groups and 1 control group in a 4×4 latin square design over 4 periods (3 wk per period ... | 2011 | 21605768 |
| variations in the 16s-23s rrna internal transcribed spacer of fibrolytic butyrivibrio isolates from the reindeer rumen. | strains of butyrivibrio are principal cellulytic bacteria in the rumen of the high arctic svalbard reindeer ( rangifer tarandus platyrhynchus ). according to phylogenetic analysis based on 16s rrna gene sequencing, butyrivibrio can be divided into three subgroups within the clostridia class of the phylum firmicutes, but the current phenotypic and genotypic differentiation within the family lachnospiraceae is insufficient. this current study describes the sequence diversity of the 16s-23s rrna in ... | 2011 | 21774627 |
| populations of select cultured and uncultured bacteria in the rumen of sheep and the effect of diets and ruminal fractions. | the objective of this study was to assess the importance of select cultured and uncultured bacteria in the rumen by quantifying their populations and the effect of diets and ruminal fractions. full-length 16s rrna gene (rrs) sequences were recovered from rumen samples using specific primers designed from partial sequences recovered previously. five uncultured bacterial operational taxonomic units (otus) were quantified using specific quantitative pcr (qpcr) in fractionated ruminal samples from s ... | 2011 | 21822435 |
| the large episomes of butyrivibrio proteoclasticus b316(t) have arisen through intragenomic gene shuttling from the chromosome to smaller butyrivibrio-specific plasmids. | the genome of butyrivibrio proteoclasticus b316(t) contains three large episomes including a 302kb chromid (bpc2) and two large plasmids of 361 (pcy360) and 186kb (pcy186). the two plasmids are largely cryptic and it is therefore difficult to gauge their contributions or importance to the biology of b. proteoclasticus. here, we provide evidence that at least bpc2 and pcy360 are essential as neither could be cured using several previously described curing techniques. we show that bpc2 exists at a ... | 2011 | 21683735 |
| extracellular polysaccharide-degrading proteome of butyrivibrio proteoclasticus. | plant polysaccharide-degrading rumen microbes are fundamental to the health and productivity of ruminant animals. butyrivibrio proteoclasticus b316(t) is a gram-positive, butyrate-producing anaerobic bacterium with a key role in hemicellulose degradation in the rumen. gel-based proteomics was used to examine the growth-phase-dependent abundance patterns of secreted proteins recovered from cells grown in vitro with xylan or xylose provided as the sole supplementary carbon source. five polysacchar ... | 2011 | 22060546 |
| faecal microbiota composition in vegetarians: comparison with omnivores in a cohort of young women in southern india. | the effect of vegetarian diets on faecal microbiota has been explored largely through culture-based techniques. the present study compared the faecal microbiota of vegetarian and omnivorous young women in southern india. faecal samples were obtained from thirty-two lacto-vegetarian and twenty-four omnivorous young adult women from a similar social and economic background. macronutrient intake and anthropometric data were collected. faecal microbiota of interest was quantified by real-time pcr wi ... | 2011 | 22182464 |
| Molecular diversity of the foregut bacteria community in the dromedary camel (Camelus dromedarius). | The molecular diversity of the foregut bacterial community in the dromedary camel (Camelus dromedarius) in Central Australia was investigated through comparative analyses of 16S rRNA gene sequences prepared from the foregut contents of 12 adult feral camels fed on native vegetation. A total of 267 full-length 16S rRNA gene clones were examined, with 151 operational taxonomic units (OTUs) identified at a 99% species-level identity cut-off criterion. The prediction of actual diversity in the foreg ... | 2011 | 21914099 |
| carbohydrate transporting membrane proteins of the rumen bacterium, butyrivibrio proteoclasticus. | the research was aimed at finding which membrane proteins of the rumen bacterium butyrivibrio proteoclasticus are involved in the uptake of carbohydrates resulting from extracellular enzymatic degradation of hemicellulose and fructan. the proteomic analysis of cells grown with fructose or xylan as the sole substrate identified 13 membrane proteins predicted to function as carbohydrate transporters. one protein detected was the membrane component of a fructose-specific phosphoenolpyruvate:sugar p ... | 2011 | 22200676 |
| toxicity of unsaturated fatty acids to the biohydrogenating ruminal bacterium, butyrivibrio fibrisolvens. | health-promoting polyunsaturated fatty acids (pufa) are abundant in forages grazed by ruminants and in vegetable and fish oils used as dietary supplements, but only a small proportion of pufa finds its way into meat and milk, because of biohydrogenation in the rumen. butyrivibrio fibrisolvens plays a major role in this activity. the aim of this study was to investigate the mechanisms by which pufa affect the growth of b. fibrisolvens, how pufa are metabolized and the metabolic response to growth ... | 2010 | 20167098 |
| phylogenetic analysis of 16s rrna gene sequences reveals rumen bacterial diversity in yaks (bos grunniens). | six matured male yaks (bos grunniens) with a mean live weight of 450 +/- 23 kg (mean +/- sd), were housed indoors in metabolism cages and fed pelleted lucerne (medicago sativum). after an adjustment period of 24 days of feeding the diet, samples of rumen content were obtained for analysis of the bacteria in the liquor. the diversity of rumen bacteria was investigated by constructing a 16s rrna gene clone library using the general bacterial primers f27 and r1492. a total of 130 clones, comprising ... | 2010 | 19757178 |
| metabolism of conjugated linoleic acids and 18 : 1 fatty acids by ruminal bacteria: products and mechanisms. | cultures of ruminal bacteria known to metabolize unsaturated fatty acids were grown in medium containing 50 microg ml(-1) of geometric and positional isomers of conjugated linoleic acid (cla) or 18 : 1 fatty acids and 37.4 % deuterium oxide to investigate the mechanisms responsible for fatty acid metabolism. butyrivibrio fibrisolvens jw11 converted cis-9,trans-11-18 : 2 and trans-9,trans-11-18 : 2 to trans-11-18 : 1 as the main product, labelled at c-9, and metabolized trans-10,cis-12-18 : 2 to ... | 2010 | 19926650 |
| structural and functional characterization of a promiscuous feruloyl esterase (est1e) from the rumen bacterium butyrivibrio proteoclasticus. | the release of polysaccharide from the plant cell wall is a key process to release the stored energy from plant biomass. within the ruminant digestive system, a host of commensal microorganisms speed the breakdown of plant cell matter releasing fermentable sugars. the presence of phenolic compounds, most notably ferulic acid (fa), esterified within the cell wall is thought to pose a significant impediment to the degradation of the plant cell wall. the structure of a fa esterase from the ruminant ... | 2010 | 20058325 |
| molecular monitoring and isolation of previously uncultured bacterial strains from the sheep rumen. | to estimate the contribution of uncultured bacterial groups to fiber degradation, we attempted to retrieve both ecological and functional information on uncultured groups in the rumen. among previously reported uncultured bacteria, fiber-associated groups u2 and u3, belonging to the low-gc gram-positive bacterial group, were targeted. pcr primers and fluorescence in situ hybridization (fish) probe targeting 16s rrna genes or rrna were designed and used to monitor the distribution of targets. the ... | 2010 | 20118379 |
| detection and identification of rumen bacteria constituting a fibrolytic consortium dominated by fibrobacter succinogenes. | a fibrolytic consortium, dominated by the rumen cellulolytic bacterium fibrobacter succinogenes, was artificially constructed on hay stems to detect and identify rumen bacteria that can potentially interact with f. succinogenes. consortium-bacterial members were determined by dgge and sequencing analysis targeted bacterial 16s rdna. an artificial consortium was formed in a 2-step incubation of hay stems; the first step with group 1, 2 or 3 f. succinogenes strains, the second step with rumen flui ... | 2010 | 20163675 |
| bacterial and protozoal communities and fatty acid profile in the rumen of sheep fed a diet containing added tannins. | this study evaluated the effects of tannins on ruminal biohydrogenation (bh) due to shifts in the ruminal microbial environment in sheep. thirteen lambs (45 days of age) were assigned to two dietary treatments: seven lambs were fed a barley-based concentrate (control group) while the other six lambs received the same concentrate with supplemental quebracho tannins (9.57% of dry matter). at 122 days of age, the lambs were slaughtered, and the ruminal contents were subjected to fatty acid analysis ... | 2010 | 20173064 |
| forage type and fish oil cause shifts in rumen bacterial diversity. | despite evidence supporting improved incorporation of beneficial polyunsaturated fatty acids (pufa) into ruminant products, such as meat and milk, following red clover and fish oil (fo) inclusion in the ruminant diet, little is known regarding the concomitant bacterial diversity. we evaluated the effects of feeding grass vs. red clover silage with incremental fo inclusion on known lipolytic, biohydrogenating, cellulolytic and proteolytic rumen bacterial communities of steers. following 14 days o ... | 2010 | 20491929 |
| changes in the rumen bacterial community in response to sunflower oil and fish oil supplements in the diet of dairy sheep. | rumen microbial biohydrogenation of dietary unsaturated fatty acids has a major effect on the process of developing healthier dairy products. this study aimed to investigate in vivo the effect of diet supplementation with sunflower (so) and fish (fo) oils on the rumen bacterial community in dairy sheep. first, 32 lactating ewes, divided in 8 lots of 4 animals each (2 lots per treatment), were fed a high-concentrate total mixed ration supplemented with 0, 2% so, 1% fo, or 2% so plus 1% fo. after ... | 2010 | 20630243 |
| the glycobiome of the rumen bacterium butyrivibrio proteoclasticus b316(t) highlights adaptation to a polysaccharide-rich environment. | determining the role of rumen microbes and their enzymes in plant polysaccharide breakdown is fundamental to understanding digestion and maximising productivity in ruminant animals. butyrivibrio proteoclasticus b316(t) is a gram-positive, butyrate-forming rumen bacterium with a key role in plant polysaccharide degradation. the 4.4 mb genome consists of 4 replicons; a chromosome, a chromid and two megaplasmids. the chromid is the smallest reported for all bacteria, and the first identified from t ... | 2010 | 20689770 |
| rumen microbial population dynamics during adaptation to a high-grain diet. | high-grain adaptation programs are widely used with feedlot cattle to balance enhanced growth performance against the risk of acidosis. this adaptation to a high-grain diet from a high-forage diet is known to change the rumen microbial population structure and help establish a stable microbial population within the rumen. therefore, to evaluate bacterial population dynamics during adaptation to a high-grain diet, 4 ruminally cannulated beef steers were adapted to a high-grain diet using a step-u ... | 2010 | 20851965 |
| a new model for the effect of ph on microbial growth: an extension of the gamma hypothesis. | to investigate the appropriateness of the extended lambert-pearson model (elpm) to model the effect of ph (as hydrogen and hydroxyl ions) over the whole biokinetic ph range in comparison with other available models. | 2010 | 20880208 |
| the effect of replacing corn with glycerol on ruminal bacteria in continuous culture fermenters. | the effects of substituting corn with glycerol on dna concentration of selected ruminal bacteria were investigated using continuous fermenters. four continuous culture fermenters were used in a 4 × 4 latin square design with four 10 days consecutive periods. treatment diets (60:40 forage to concentrate) were fed at 45 g/day dry matter (dm) in three equal portions. glycerol (0.995 g/g glycerol) was used to replace corn in a grain mix at proportions of 0% (t0; control), 15% (t15), 30% (t30) and 45 ... | 2010 | 20880288 |
| paenibacillus polymyxa jb05-01-1 and its perspectives for food conservation and medical applications. | the aim of this study was to isolate a novel bacterial strain with strong and broad spectrum antibacterial activity from a livestock feed prebiotic supplement. a novel strain, termed paenibacillus polymyxa jb05-01-1, was isolated using traditional microbiological methods and identified on the basis of its phenotypic and biochemical properties as well as its 16s rrna gene sequence. this strain was able to inhibit growth of gram-negative bacteria including escherichia coli rr1, pseudomonas fluores ... | 2010 | 21132276 |
| dominant bacterial communities in the rumen of gayals (bos frontalis), yaks (bos grunniens) and yunnan yellow cattle (bos taurs) revealed by denaturing gradient gel electrophoresis. | the dominant rumen bacteria in gayals, yaks and yunnan yellow cattle were investigated using pcr-dgge approach. the analysis of dgge profiles, identification of dominant bands and phylogenetic analysis 16s rdna sequences in dgge profiles were combined to reveal the dominant bacterial communities and compared the differences between those cattle species. dgge profiles revealed that gayals had the most abundant dominant bacteria and the lowest similarity of intraspecies between individuals than ot ... | 2010 | 21140219 |
| production of conjugated linoleic acid (cla) by bifidobacterium breve lmc520 and its compatibility with cla-producing rumen bacteria. | this study was performed to characterize the ability of an active bifidobacterium strain to produce conjugated linoleic acid (cla) and to test its possible utilization as a probiotic compatible to the ruminal condition. bifidobacterium breve lmc520 can actively convert linoleic acid (la) to cis-9,trans-11-cla, which is a major isomer derived from microbial conversion. lmc520 showed reasonable tolerance under acidic conditions (ph 2.5 with 1% pepsin) and in the presence of oxgall (0-3%). the grow ... | 2010 | 21192703 |
| bacterial diversity in the rumen of gayals (bos frontalis), swamp buffaloes (bubalus bubalis) and holstein cow as revealed by cloned 16s rrna gene sequences. | libraries of rumen bacterial 16s rrna gene sequences of gayals (bos frontalis) and swamp buffaloes (bubalus bubalis) were cloned and sequenced in the present work to compare the bacterial diversity with the third published library of holstein cow. sequence similarity of 97% was used as the definition of operational taxonomic unit (otu). the majority of the 470 sequences retrieved fell into the phyla of low g + c subdivision (329 sequences) and cytophaga-flexibacter-bacteroides (cfb, 123 sequence ... | 2010 | 19662514 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| investigating unsaturated fat, monensin, or bromoethanesulfonate in continuous cultures retaining ruminal protozoa. ii. interaction of treatment and presence of protozoa on prokaryotic communities. | increasing the consistency of responses to reduce emissions of ruminal methane and nitrogenous wastes into the environment using microbial inhibitors requires an accurate assessment of microbial community profiles. in addition to direct inhibition of methanogens by feed additives, protozoa are often targeted for inhibition because their close physical association with endo- and ectosymbionts stimulates methanogenesis in the rumen. in this study, we first modified a continuous culture system to m ... | 2009 | 19620670 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |