| effects of glycerol on the growth, adhesion, and cellulolytic activity of rumen cellulolytic bacteria and anaerobic fungi. | the effect of glycerol on the growth, adhesion, and cellulolytic activity of two rumen cellulolytic bacterial species, ruminococcus flavefaciens and fibrobacter succinogenes subsp. succinogenes, and of an anaerobic fungal species, neocallimastix frontalis, was studied. at low concentrations (0.1-1%), glycerol had no effect on the growth, adhesion, and cellulolytic activity of the two bacterial species. however, at a concentration of 5%, it greatly inhibited their growth and cellulolytic activity ... | 1992 | 1368974 |
| use of dna probes to monitor nutritional effects on ruminal prokaryotes and fibrobacter succinogenes s85. | we used dna probes to study dietary effects on the prokaryotic population in the rumen. procedures used to isolate and quantify prokaryotic 16s ribosomal rna (rrna) from the rumen using universal and species-specific dna probes were evaluated. in this experiment, three ruminally fistulated steers were fed orchard-grass hay, and ruminal digesta were collected at 0, 3, and 9 h after offering hay (0800). samples of ruminal digesta were taken from the interior portion of the digesta mat and from the ... | 1992 | 1374753 |
| two beta-glucosidase activities in fibrobacter succinogenes s85. | few bacteria are capable of degrading crystalline cellulose but there is considerable interest in the properties of enzyme systems with this capability. in the bovine and ovine rumen the principal cellulolytic bacterium is fibrobacter (formerly bacteroides) succinogenes. the cellulase system of this organism is composed of multiple enzyme components, including a constitutive and cell-associated beta-glucosidase active against cellobiose. the properties of the beta-glucosidase activity have been ... | 1992 | 1399917 |
| degradation of maize stem by two rumen fungal species, piromyces communis and caecomyces communis, in pure cultures or in association with cellulolytic bacteria. | two species of rumen fungi, piromyces (piromonas) communis fl and caecomyces (sphaeromonas) communis fg10, were cultured alone or in association with the cellulolytic bacteria ruminococcus flavefaciens or fibrobacter succinogenes on maize stem. a kinetic study of the degradation of the substrate was then made. after 48 h of culture, all non-lignified tissues observed by scanning electron microscopy disappeared with p communis and degradation was as complete as that observed in the rumen. in cont ... | 1992 | 1418394 |
| purification, characterization, and mode of action of endoxylanases 1 and 2 from fibrobacter succinogenes s85. | two different endoxylanases (1,4-beta-d-xylan xylanohydrolases, ec 3.2.1.8), designated 1 and 2, have been purified by column chromatography to apparent homogeneity from the nonsedimentable extracellular culture fluid of the strictly anaerobic, ruminal bacterium fibrobacter succinogenes s85 grown on crystalline cellulose. endoxylanases 1 and 2 were shown to be basic proteins of 53.7 and 66.0 kda, respectively, with different ph and temperature optima, as well as different substrate hydrolysis ch ... | 1992 | 1539970 |
| futile cycling of glycogen in fibrobacter succinogenes as shown by in situ 1h-nmr and 13c-nmr investigation. | glycogen was synthesized during all the growth phases in the rumen anaerobic cellulolytic bacterium fibrobacter succinogenes. glycogen synthesis and degradation were monitored using in situ 13c and 1h-nmr spectroscopy in resting cells of f. succinogenes. the cells were incubated at 37 degrees c under anaerobic conditions with [1-13c]glucose and [2-13c]glucose. 1h-nmr spectra were used to quantify enrichment by 13c of metabolism products. glucose was utilized for energy requirements of the bacter ... | 1992 | 1628646 |
| enzymes associated with metabolism of xylose and other pentoses by prevotella (bacteroides) ruminicola strains, selenomonas ruminantium d, and fibrobacter succinogenes s85. | prevotella (bacteroides) ruminicola strains b(1)4 and s23 and selenomonas ruminantium strain d used xylose as the sole source of carbohydrate for growth, whereas fibrobacter succinogenes was unable to metabolize xylose. prevotella ruminicola strain b(1)4 exhibited transport activity for xylose. in contrast, f. succinogenes lacked typical xylose uptake activity but did exhibit low binding potential for the sugar. prevotella ruminicola strains b(1)4 and s23 as well as s. ruminantium d showed low x ... | 1992 | 1643581 |
| type ii dna restriction-modification system and an endonuclease from the ruminal bacterium fibrobacter succinogenes s85. | fibrobacter succinogenes is an important cellulolytic bacterium found in the rumen and cecum of herbivores. numerous attempts to introduce foreign dna into f. succinogenes s85 have failed, suggesting the presence of genetic barriers in this organism. results from this study clearly demonstrate that f. succinogenes s85 possesses a type ii restriction endonuclease, fsui, which recognizes the sequence 5'-gg(a/t)cc-3'. analysis of the restriction products on sequencing gels showed that fsui cleaves ... | 1992 | 1644754 |
| degradation of cellulose and forage fiber fractions by ruminal cellulolytic bacteria alone and in coculture with phenolic monomer-degrading bacteria. | we hypothesized that bacterial species capable of metabolizing phenolic monomers may act as catalysts for forage fiber breakdown by increasing microbial access to cell wall polysaccharides. ruminal cellulolytic bacteria alone and in combination with phenolic-degrading bacteria were examined for differences in their ability to degrade fiber fractions of alfalfa or bromegrass. electron micrographs of fibrobacter succinogenes s85 cultured in combination with the ruminal phenolic-degrading organisms ... | 1991 | 1667013 |
| fluorescent-oligonucleotide probing of whole cells for determinative, phylogenetic, and environmental studies in microbiology. | fluorescent-dye-conjugated oligonucleotides were used to classify 14 fibrobacter strains by fluorescence microscopy. on the basis of partial 16s rrna sequences of six fibrobacter strains, four hybridization probes were designed to discriminate between the species fibrobacter succinogenes and fibrobacter intestinalis and to identify f. succinogenes subsp. succinogenes. after in situ hybridization to whole cells of the six sequenced strains, epifluorescence microscopy confirmed probe specificity. ... | 1990 | 1688842 |
| antigenic nature of the chloride-stimulated cellobiosidase and other cellulases of fibrobacter succinogenes subsp. succinogenes s85 and related fresh isolates. | polyclonal and monoclonal antibodies to the cl-stimulated cellobiosidase of fibrobacter succinogenes subsp. succinogenes s85 reacted with numerous proteins of both higher and lower molecular weights from f. succinogenes subsp. succinogenes s85, but not with escherichia coli proteins, and only one protein each from butyrivibrio fibrisolvens and ruminococcus albus. different profiles were observed for western blots (immunoblots) of peptide digests of both the purified enzyme from f. succinogenes a ... | 1990 | 1692677 |
| endafs, a novel family e endoglucanase gene from fibrobacter succinogenes ar1. | the complete nucleotide sequence of endafs, an endoglucanase gene isolated from the ruminal anaerobe fibrobacter succinogenes ar1, was determined. endafs encodes two overlapping open reading frames (orf1 and orf2), and it was proposed that a -1 ribosomal frameshift was required to allow contiguous synthesis of a 453-amino-acid endoglucanase. a proline- and threonine-rich region at the c terminus of orf1 and rare codons for arginine and threonine were coincident with the proposed frameshift site. ... | 1991 | 1708767 |
| structure of the clostridium thermocellum gene licb and the encoded beta-1,3-1,4-glucanase. a catalytic region homologous to bacillus lichenases joined to the reiterated domain of clostridial cellulases. | the nucleotide sequence of the clostridium thermocellum gene licb, coding for a thermoactive beta-1,3-1,4-glucanase, has been determined. the gene is located downstream, but in opposite orientation to the beta-glucosidase gene bgla. a coding region of 1002 bp is flanked by canonical promoter and transcription terminator sequences. the primary translation product of the licb gene has a predicted molecular mass of 37,896 da. the protein sequence can be divided into several discrete segments: an n- ... | 1992 | 1740123 |
| development of the rumen digestive functions in lambs placed in a sterile isolator a few days after birth. | the development of the rumen digestive functions was studied in lambs placed in sterile isolators at 1, 4, 8 or 9 days of age to define the role of the bacterial species that colonize the rumen just after birth. the values of the main rumen digestive parameters (ph, concentrations of volatile fatty acid, ammonia, lactic acid) in these lambs were close to those observed in conventional controls. likewise, the digestive utilisation of the dry matter and starch was comparable in isolated and contro ... | 1991 | 1768310 |
| cloning of a xylanase gene from fibrobacter succinogenes 135 and its expression in escherichia coli. | a genomic library consisting of 4- to 7-kb ecori dna fragments from fibrobacter succinogenes 135 was constructed using a phage vector, lambda gtwes lambda b, and escherichia coli ed8654 as the host bacterium. two positive plaques, designated lambda fsx101 and lambda fsx102, were identified. the inserts were 10.5 and 9.8 kb, respectively. a 2.3-kb ecori fragment that was subcloned from lambda fsx101 into pbr322 also showed xylanase activity. southern blot analysis showed that the cloned ecori fra ... | 1991 | 1913358 |
| molecular cloning, expression, and characterization of endoglucanase genes from fibrobacter succinogenes ar1. | a cosmid gene library was constructed in escherichia coli from genomic dna isolated from the ruminal anaerobe fibrobacter succinogenes ar1. clones were screened on carboxymethyl cellulose, and 8 colonies that produced large clearing zones and 25 colonies that produced small clearing zones were identified. southern blot hybridization revealed the existence of at least three separate genes encoding cellulase activity. prc093, which is representative of cosmid clones that produce large clearing zon ... | 1991 | 2014986 |
| the involvement of transcriptional read-through from internal promoters in the expression of a novel endoglucanase gene fsenda, from fibrobacter succinogenes ar1. | two distinct mrna transcripts were synthesized in escherichia coli during expression of fsenda, an endoglucanase gene from fibrobacter succinogenes ar1. expression of fsenda required a ribosomal frameshift between open reading frame 1 (orf1) and orf2 to allow contiguous translation of a 453 amino acid protein (1). the primary transcript initiated upstream of orf1 and the secondary transcript from within orf1. both transcripts terminated downstream of orf2 and termination was essential for endogl ... | 1991 | 2027774 |
| the hydrolysis of lucerne cell-wall monosaccharide components by monocultures or pair combinations of defined ruminal bacteria. | the defined ruminal bacterial strains fibrobacter succinogenes s85, ruminococcus flavefaciens fd1, ruminococcus albus 7, butyrivibrio fibrisolvens d1, and bacteroides ruminicola ga33 were grown, in monocultures or as combinations of pair strains, on isolated lucerne cell-walls (cw) as the sole carbohydrate substrate. fibrobacter succinogenes s85 was the dominant strain determining extent of cw hydrolysis in all combinations with s85. the hydrolysis of cellulose, xylan, hemicellulose side-sugars, ... | 1991 | 2030098 |
| cellobiose uptake by the cellulolytic ruminal anaerobe fibrobacter (bacteroides) succinogenes. | cellobiose transport by the cellulolytic ruminal anaerobe fibrobacter (bacteroides) succinogenes was measured using randomly tritiated cellobiose. when assayed at the same concentration (1 mm), total cellobiose uptake was one-fourth to one-third that of total glucose uptake. the abilities of f. succinogenes to transport cellobiose or glucose were not affected by the sugar on which the cells were grown. aspects of the simultaneous transport of [14c(u)]glucose and [3h(g)]cellobiose, the failure of ... | 1991 | 2059920 |
| purification and properties of an acetylxylan esterase from fibrobacter succinogenes s85. | an acetylxylan esterase (ec 3.1.1.6) was purified to apparent homogeneity from the nonsedimentable extracellular culture fluid of fibrobacter succinogenes s85 grown on cellulose. this enzyme had an apparent molecular mass of 55 kda and an isoelectric point of 4.0. the temperature and ph optima were 45 degrees c and 7.0, respectively. the apparent km and vmax were 2.7 mm and 9,100 u/mg, respectively, for the hydrolysis of alpha-naphthyl acetate. the enzyme cleaved acetyl residues from birchwood a ... | 1990 | 2082827 |
| extracellular beta-galactosidase activity of a fibrobacter succinogenes s85 mutant able to catabolize lactose. | fibrobacter succinogenes s85 is unable to grow with lactose as the source of carbohydrate, although it does exhibit low beta-galactosidase (ec 3.2.1.23) activity. spontaneous mutants of strain s85 able to grow on lactose were isolated after spreading cells on a chemically defined agar medium with lactose as the carbohydrate source. a lactose-catabolizing isolate, designated l2, exhibited a sodium dodecyl sulfate-polyacrylamide gel electrophoresis protein profile and an immunoblot profile with po ... | 1990 | 2128006 |
| dna sequence of a fibrobacter succinogenes mixed-linkage beta-glucanase (1,3-1,4-beta-d-glucan 4-glucanohydrolase) gene. | the dna sequence of a mixed-linkage beta-glucanase (1,3-1,4-beta-d-glucan 4-glucanohydrolase [ec 3.2.1.73]) gene from fibrobacter succinogenes cloned in escherichia coli was determined. the general features of this gene are very similar to the consensus features for other gram-negative bacterial genes. the gene product was processed for export in e. coli. there is a high level of sequence homology between the structure of this glucanase and the structure of a mixed-linkage beta-glucanase from ba ... | 1990 | 2193918 |
| [use of glucose and cellobiose by 3 strains of fibrobacter succinogenes]. | f succinogenes strains s85, 128 and 095 were compared with respect to their growth using glucose and/or cellobiose as the carbon and energy substrate(s) and their capacities to degrade cellulose. the growth rate of f succinogenes strain s85 was the same using glucose or cellobiose, whereas the growth rates of strains 128 and 095 were about thrice the rate when using cellobiose. strain s85 could simultaneously use glucose and cellobiose, while strains 128 and 095 tended to use preferentially gluc ... | 1990 | 2206331 |
| study of the mode of action and site-specificity of the endo-(1----4)-beta-d-glucanases of the fungus penicillium pinophilum with normal, 1-3h-labelled, reduced and chromogenic cello-oligosaccharides. | the modes of action of the five major endo-(1----4)-beta-d-glucanases (i, ii, iii, iv and v) purified from penicillium pinophilum cellulase were compared by h.p.l.c. analysis, with normal, 1-3h-labelled and reduced cello-oligosaccharides and 4-methylumbelliferyl glycosides as substrates. significant differences were observed in the preferred site of cleavage even when substrates with the same number of glycosidic bonds were compared. thus, although endoglucanase i was unable to attack normal cel ... | 1990 | 2317193 |
| cellulose digestion and cellulase regulation and distribution in fibrobacter succinogenes subsp. succinogenes s85. | fibrobacter succinogenes subsp. succinogenes s85 initiated growth on microcrystalline cellulose without a lag whether inoculated from a glucose, cellobiose, or cellulose culture. during growth on cellulose, there was no accumulation of soluble carbohydrate. when the growth medium contained either glucose or cellobiose in combination with microcrystalline cellulose, there was a lag in cellulose digestion until all of the soluble sugar had been utilized, suggesting an end product feedback mechanis ... | 1990 | 2339881 |
| regulation and distribution of fibrobacter succinogenes subsp. succinogenes s85 endoglucanases. | the distribution of endoglucanase activities in cultures of fibrobacter succinogenes subsp. succinogenes s85 grown on different carbon sources was examined by a variety of biochemical and immunological techniques. total culture endoglucanase activity was primarily cell associated and was expressed constitutively, although synthesis of endoglucanase 1 (eg1) was repressed by cellobiose. western immunoblotting showed that eg1 and eg3 were released into the culture fluid during growth, while eg2 rem ... | 1990 | 2339882 |
| factors affecting adhesion of fibrobacter succinogenes subsp. succinogenes s85 and adherence-defective mutants to cellulose. | fibrobacter succinogenes subsp. succinogenes s85, formerly bacteroides succinogenes, adheres to crystalline cellulose present in the culture medium. when the cells are suspended in buffer, adhesion is enhanced by increasing the ionic strength. heat, glutaraldehyde, trypsin, and pronase treatments markedly reduce the extent of adhesion. treatment with dextrinase, modification of amino and carboxyl groups with formalin or other chemical agents, and inclusion of either albumin (1%) or tween 80 (0.5 ... | 1989 | 2619302 |
| structure of the cel-3 gene from fibrobacter succinogenes s85 and characteristics of the encoded gene product, endoglucanase 3. | the cel-3 gene cloned from fibrobacter succinogenes into escherichia coli coded for the enzyme eg3, which exhibited both endoglucanase and cellobiosidase activities. the gene had an open reading frame of 1,974 base pairs, coding for a protein of 73.4 kilodaltons (kda). however, the enzyme purified from the osmotic shock fluid of e. coli was 43 kda. the amino terminus of the 43-kda protein matched amino acid residue 266 of the protein coded for by the open reading frame, indicating proteolysis in ... | 1989 | 2676979 |
| family a cellulases: two essential tryptophan residues in endoglucanase iii from trichoderma reesei. | three tryptophan residues are readily oxidised by n-bromosuccinimide in endoglucanase iii from trichoderma reesei. evidence was obtained that the residue first modified is situated in the cellulose-binding domain and the second in the enzyme's catalytic site. the latter influences the binding and hydrolysis of soluble substrates. the modification of a third residue does not further affect the catalytic properties. the present results complement published data concerning other identified catalyti ... | 1995 | 7492576 |
| the use of 16s rrna-targeted oligonucleotide probes to study competition between ruminal fibrolytic bacteria: development of probes for ruminococcus species and evidence for bacteriocin production. | a total of six oligonucleotide probes, complementary to the 16s rrna, were evaluated for quantitative and determinative studies of ruminococcus albus and ruminococcus flavefaciens. on the basis of specificity studies, probes for r. albus (probe ral196) and r. flavefaciens (probe rfl196) were selected to quantitate these species in mixed culture. in combination with a fibrobacter succinogenes s85 subspecies probe (sub1) and a domain bacteria (formerly kingdom eubacteria) probe (eub338), they were ... | 1994 | 7527201 |
| the use of 16s rrna-targeted oligonucleotide probes to study competition between ruminal fibrolytic bacteria: pure-culture studies with cellulose and alkaline peroxide-treated wheat straw. | specific oligonucleotide probes targeted to sites on the 16s rrna of ruminococcus albus 8, ruminococcus flavefaciens fd-1, and fibrobacter succinogenes s85 and a domain bacteria probe were used to study bacterial interactions during the fermentation of cellulose and alkaline hydrogen peroxide-treated wheat straw in monocultures, dicultures, and tricultures. results showed that r. albus 8 inhibited the growth of r. flavefaciens fd-1 when grown as a diculture with cellulose or alkaline hydrogen pe ... | 1994 | 7527202 |
| taxon-specific probes for the cellulolytic genus fibrobacter reveal abundant and novel equine-associated populations. | a total of six 16s rrna targeted oligonucleotide probes were used to quantify fibrobacter abundance and diversity in the gastrointestinal contents of a pony. approximately 12% of the total 16s rrna extracted from cecal contents hybridized with a fibrobacter genus-specific probe and a fibrobacter succinogenes species-specific probe. however, no significant hybridization was observed with a probe for the species. fibrobacter intestinalis or with three probes for f. succinogenes subspecies. this su ... | 1995 | 7538274 |
| ruminal microbial digestion in free-living, in captive lichen-fed, and in starved reindeer (rangifer tarandus tarandus) in winter. | in free-living (fl) reindeer eating a natural mixed winter diet dominated by lichens, captive (cf) reindeer fed pure lichens ad libitum, and cf reindeer subsequently starved for 1 day (cs1 reindeer) or 4 days (cs4 reindeer), the dominant rumen anaerobic bacteria were characterized, their population densities were estimated, and ruminal ph and volatile fatty acid concentrations were determined. in the fl reindeer, the total median viable anaerobic bacterial population ranged from 18 x 10(8) to 35 ... | 1995 | 7574599 |
| the cellular location of prevotella ruminicola beta-1,4-d-endoglucanase and its occurrence in other strains of ruminal bacteria. | prevotella ruminicola b(1)4, tc1-1, tf1-3, and ts1-5 all produced immunologically cross-reacting 88- and 82-kda carboxymethyl cellulases (cmcases). p. ruminicola 23, 118b, 20-63, and 20-78 had much lower cmcase activities, and western blots (immunoblots) showed no cross-reaction with the b(1)4 cmcase antiserum. fibrobacter succinogenes s85 and selenomonas ruminantium hd4 and d produced cmcase, but these enzymes were smaller and did not cross-react with the b(1)4 cmcase antiserum. the b(1)4 cmcas ... | 1995 | 7574639 |
| cellodextrin efflux by the cellulolytic ruminal bacterium fibrobacter succinogenes and its potential role in the growth of nonadherent bacteria. | when glucose or cellobiose was provided as an energy source for fibrobacter succinogenes, there was a transient accumulation (as much as 0.4 mm hexose equivalent) of cellobiose or cellotriose, respectively, in the growth medium. nongrowing cell suspensions converted cellobiose to cellotriose and longer-chain cellodextrins, and in this case the total cellodextrin concentration was as much as 20 mm (hexose equivalent). because cell extracts of glucose- or cellobiose-grown cells cleaved cellobioise ... | 1995 | 7646013 |
| the in vitro uptake and metabolism of peptides and amino acids by five species of rumen bacteria. | streptococcus bovis jb1, prevotella ruminicola b(1)4, selenomonas ruminantium z108, fibrobacter succinogenes s85 and anaerovibrio lipolytica 5s were incubated with either 14c-peptides (mol. wt, 200-1000) or 14c-amino acids to compare their rates of uptake and metabolism. in experiment 1, the bacteria were grown and incubated in a complex medium, but no uptake of 14c-labelled substrates occurred. when casein digest was omitted, uptake rates of 14c-peptides were different (p < 0.01) with each spec ... | 1995 | 7698948 |
| nutrient transport by ruminal bacteria: a review. | fermentation pathways have been elucidated for predominant ruminal bacteria, but information is limited concerning the specific transport mechanisms used by these microorganisms for c, energy, and n sources. in addition, it is possible that changes in ruminal environmental conditions could affect transport activity. five carrier-mediated soluble nutrient transport mechanisms have been identified in bacteria: 1) facilitated diffusion, 2) shock sensitive systems, 3) proton symport, 4) na+ symport, ... | 1994 | 7730197 |
| comparative analyses reveal a highly conserved endoglucanase in the cellulolytic genus fibrobacter. | an rna probe complementary to the endoglucanase 3 gene (cel-3) of fibrobacter succinogenes s85 hybridized to chromosomal dnas from isolates representing the genetic diversity of the genus. the probe was subsequently used to identify putative cel-3-containing clones from genomic libraries of representative fibrobacter isolates. comparative sequence analyses of the cloned cel-3 genes confirmed that cel-3 is conserved among fibrobacter isolates and that the ancestral cel-3 gene appears to have coev ... | 1995 | 7730288 |
| gene sequence and analysis of protein domains of egb, a novel family e endoglucanase from fibrobacter succinogenes s85. | the endoglucanase gene (endb) of fibrobacter succinogenes s85 encodes a protein of 555 amino acids (egb) with a m(r) of 62,500. egb shows homology with cellulases belonging to family e. residues involved in the catalytic activity of celd from clostridium thermocellum are also found in egb. structure predictions suggest that egb, like celd, comprises a large alpha-helical catalytic domain plus a beta-strand domain of unknown function located in the n-terminal part of the protein. construction of ... | 1994 | 7851752 |
| phosphorylation of glucose by a guanosine-5'-triphosphate (gtp)-dependent glucokinase in fibrobacter succinogenes subsp. succinogenes s85. | cell extracts of fibrobacter succinogenes subsp. succinogenes s85 phosphorylated glucose with a gtp-dependent glucokinase. the enzyme showed little activity with atp (12% of that with gtp). of other phosphate donors tested, only dgtp and itp gave high glucokinase activities. dialyzed extracts required mg+2 and k+ for maximal activity. in potassium phosphate buffer, glucokinase showed maximum activity at ph 7.5 with glucose-6-phosphate dehydrogenase as the coupling enzyme. in this assay, glucokin ... | 1994 | 7979872 |
| cellulose hydrolysis by the cellulases from trichoderma reesei: adsorptions of two cellobiohydrolases, two endocellulases and their core proteins on filter paper and their relation to hydrolysis. | separate binding of several purified cellulolytic components of trichoderma reesei on to filter paper was studied and concomitant hydrolysis rates evaluated. enhancement of mass transfer from the bulk liquid to the solid substrate by agitation has two different effects on adsorption depending on the type of enzyme: (i) the fraction of cellobiohydrolase ii (cbh ii) and endoglucanase iii (eg iii) bound at equilibrium is increased, whereas (ii) the rate but not the extent of cellobiohydrolase i (cb ... | 1994 | 7980450 |
| degradation and utilization of forage hemicellulose by rumen bacteria, singly in coculture or added sequentially. | procedures for sequential addition experiments were developed to study the mechanisms involved in the synergistic and inhibitory interactions observed in forage hemicellulose digestion by rumen bacterial cocultures. one organism was allowed to ferment a forage substrate, the culture tube was sterilized and then inoculated with a second organism. no differences were found in the extent of degradation or utilization between fermentations sterilized by oxidation or heat, and based on ease of handli ... | 1994 | 8002478 |
| enzymatic specificities and modes of action of the two catalytic domains of the xync xylanase from fibrobacter succinogenes s85. | the xylanase xync of fibrobacter succinogenes s85 was recently shown to contain three distinct domains, a, b, and c (f. w. paradis, h. zhu, p. j. krell, j. p. phillips, and c. w. forsberg, j. bacteriol. 175:7666-7672, 1993). domains a and b each bear an active site capable of hydrolyzing xylan, while domain c has no enzymatic activity. two truncated proteins, each containing a single catalytic domain, named xync-a and xync-b were purified to homogeneity. the catalytic domains a and b had similar ... | 1994 | 8021170 |
| features of the cellodextrinase gene from fibrobacter succinogenes s85. | the nucleotide sequence of a 2.3-kb dna fragment containing a cellodextrinase gene (ceda) from the ruminal anaerobe fibrobacter succinogenes s85 was determined. activity was expressed from this fragment when it was cloned in both orientations in pbluescript ks+ and sk-, indicating a functional f. succinogenes promoter in escherichia coli. promoter sequences (ttgaaca and aataa) were identified upstream of the atg initiation codon preceded by a putative ribosome binding site. the ceda open reading ... | 1994 | 8076254 |
| identification of an essential glutamate residue in the active site of endoglucanase iii from trichoderma reesei. | n-propyl, n-butyl and n-pentyl beta-cellobiosides with a reactive omega-epoxide in their aglycon completely and irreversibly inactivate endoglucanase iii from trichoderma reesei. the pentyl derivative was found to be most effective. from these affinity labeling experiments evidence was found for the implication of glu329 in the reaction mechanism. this is discussed in relation to other structural/functional data known for endoglucanase iii and several other family a glycanases. | 1993 | 8093602 |
| cellulose hydrolysis by the cellulases from trichoderma reesei: a new model for synergistic interaction. | the hydrolysis of whatman no. 1 filter paper by purified cellulolytic components from trichoderma reesei and the synergistic action of binary combinations of these enzymes on the same substrate were investigated. at 20 milligrams filter paper, enzyme concentrations needed to obtain half-maximal hydrolysis rates (ke values) were in the 3-4 microm range for the cellobiohydrolases (cbhs) and 0.05-0.10 microm for the endoglucanases (egs). catalytic-core proteins of cbh i and eg iii, lacking the cell ... | 1994 | 8141786 |
| interactions between rumen bacterial strains during the degradation and utilization of the monosaccharides of barley straw cell-walls. | pure cultures and pair-combinations of strains representative of the rumen cellulolytic species ruminococcus flavefaciens, fibrobacter succinogenes and butyrivibrio fibrisolvens were grown on cell-wall materials from barley straw. of the pure cultures, r. flavefaciens solubilized straw most rapidly. the presence of b. fibrisolvens, which was unable to degrade straw extensively in pure culture, increased the solubilization of dry matter by r. flavefaciens and the solubilization of cell-wall carbo ... | 1994 | 8157547 |
| interactions between proteolytic and cellulolytic rumen bacteria during hydrolysis of plant cell wall protein. | during the degradation of the plant cell wall protein of dried alfalfa, interactions may occur between hydrolytic activities of cellulolytic (ruminococcus albus or fibrobacter succinogenes) and proteolytic (prevotella ruminicola or butyrivibrio fibrisolvens) bacteria. in vitro the hydrolysis of these protein compounds begins after the depolymerization of the cell wall polysaccharides has started. maximal degradation of cell wall protein of dried alfalfa (37.2%) was obtained with cocultures of pr ... | 1993 | 8216756 |
| digestion of cell-wall monosaccharides of ryegrass and alfalfa hays by the ruminal bacteria fibrobacter succinogenes and butyrivibrio fibrisolvens. | the ruminal bacteria fibrobacter succinogenes strains s85 and bl2 were grown in monocultures or in coculture with strain d1 of butyrivibrio fibrisolvens, and the solubilization of ryegrass and alfalfa cell walls (cw) and digestion of cw monosaccharides were measured. fibrobacter succinogenes monocultures and cocultures with b. fibrisolvens d1 degraded 58-69% of ryegrass cw, solubilizing 67-78% of cw glucose, 65-71% of cw xylose, 69-75% of hemicellulose, and 68-77% of total cw monosaccharides. wh ... | 1993 | 8221378 |
| separation of outer and cytoplasmic membranes of fibrobacter succinogenes and membrane and glycogen granule locations of glycanases and cellobiase. | the outer membrane (om) of fibrobacter succinogenes was isolated by a combination of salt, sucrose, and water washes from whole cells grown on either glucose or cellulose. the cytoplasmic membrane (cm) was isolated from om-depleted cells after disruption with a french press. the om and membrane vesicles isolated from the extracellular culture fluid of cellulose-grown cells had a higher density, much lower succinate dehydrogenase activity, and sodium dodecyl sulfate-polyacrylamide gel electrophor ... | 1993 | 8226622 |
| effects of dilution rate and ph on the ruminal cellulolytic bacterium fibrobacter succinogenes s85 in cellulose-fed continuous culture. | the ruminal cellulolytic bacterium fibrobacter succinogenes s85 was grown in cellulose-fed continuous culture at 22 different combinations of dilution rate (d, 0.014-0.076 h-1) and extracellular ph (6.11-6.84). effects of ph and d on the fermentation were determined by subjecting data on cellulose consumption, cell yield, product yield (succinate, acetate, formate), and soluble sugar concentration to response surface analysis. the extent of cellulose conversion decreased with increasing d. first ... | 1993 | 8239881 |
| the xync gene from fibrobacter succinogenes s85 codes for a xylanase with two similar catalytic domains. | the xync gene of fibrobacter succinogenes s85 codes for a 66.4-kda xylanase which consists of three distinct domains separated by two flexible regions rich in serine residues. domains a and b of xync code for catalytic domains with 56.5% identity and 9.6% similarity with each other, and both domains share homology with xylanases of ruminococcus flavefaciens, neocallimastix patriciarum, clostridium acetobutylicum, bacillus pumilus, bacillus subtilis, and bacillus circulans. more than 88% of the x ... | 1993 | 8244936 |
| [study of obligate anaerobic bacterial sensitivity to tinidazole and metronidazole (determination of minimal inhibiting concentration--mic)]. | comparative susceptibility testing of 428 strains of obligate anaerobic bacteria belonging to genera propionibacterium, arachnia, actinomyces, bacteroides, prevotella, porphyromonas, anaerorhabdus, fibrobacter, fusobacterium, peptostreptococcus and clostridium to metronidazole and tinidazole was performed. the study of the susceptibility of anaerobic bacteria was carried out by the method of serial dilution in brucella agar according to finegold and sutter (1972). strains of b. fragilis species, ... | 1993 | 8249400 |
| supplemental protein influences on carbohydrate degradation and bacterial 16s ribosomal ribonucleic acid. | this research examined the mechanism by which soybean protein stimulates growth of mixed ruminal anaerobes and degrades structural polysaccharides in vitro. soybean meal, isolated soy protein, or branched-chain vfa was added to orchardgrass hay substrate in experiment 1. cell-wall degradation increased 14.5% over that of the control by protein addition. protein addition resulted in 1.3- to 1.5-fold increases in bacterial growth. hybridization with a 16s probe specific for fibrobacter succinogene ... | 1993 | 8270691 |
| analysis of bacterial phospholipid markers and plant monosaccharides during forage degradation by ruminococcus flavefaciens and fibrobacter succinogenes in co-culture. | marker components of the phospholipids of ruminococcus flavefaciens and fibrobacter succinogenes were identified for studies on the degradation of forage by these bacteria growing in mixed culture. the principal fatty acid methyl esters and dimethyl acetals detected varied between strains and were influenced by the addition of a mixture of higher volatile fatty acids and vitamins to the medium, but these effects were small compared to the differences between the species. when two strains of r. f ... | 1993 | 8277262 |
| the effect of tetronasin and monensin on fermentation, microbial numbers and the development of ionophore-resistant bacteria in the rumen. | the gram-negative rumen bacteria fibrobacter succinogenes s85, prevotella ruminicola m384 and veillonella parvula l59 were grown in media containing successively increasing concentrations of the ionophores, monensin and tetronasin. all three species became more resistant to the ionophore with which they were grown. increased resistance to one ionophore caused increased resistance to the other, and cross-resistance to another ionophore--lasalocid--and an antibiotic--avoparcin. recovery of tetrona ... | 1993 | 8407673 |
| inhibition of ruminal cellulose fermentation by extracts of the perennial legume cicer milkvetch (astragalus cicer). | cicer milkvetch (astragalus cicer l.) is a perennial legume used as a pasture or rangeland plant for ruminants. a study was undertaken to determine whether reported variations in its ruminal digestibility may be related to the presence of an antinutritive material. in vitro fermentation of neutral detergent fiber (ndf) of cicer milkvetch by mixed rumen microflora was poorer than was the fermentation of ndf in alfalfa (medicago sativa l.). fermentation of cicer milkvetch ndf was improved by preex ... | 1993 | 8434909 |
| mode of action of endoglucanase iii from trichoderma reesei. | endoglucanase iii (eg iii) was purified to homogeneity from the culture medium of trichoderma reesei qm 9414. it has a molecular mass of 48 kda, and an isoelectric point of 5.1. maximal activity was observed between ph4 and 5. celloligosaccharides and their chromophoric derivatives were used as substrates, and the reaction products were analysed by quantitative h.p.l.c. nucleophilic competition experiments (between methanol and water) allowed unequivocal assessment of cleavage sites. eg iii pref ... | 1993 | 8435082 |
| cloning of a cellulase gene from the rumen anaerobe fibrobacter succinogenes sd35 and partial characterization of the gene product. | a gene encoding an enzyme which degrades cellulose (end-1) was isolated from a library of fibrobacter succinogenes sd35 dna fragments and expressed in puc18. the product of end-1 showed significant activity against carboxymethylcellulose but relatively minor activity against lichenan, xylan and avicel. the nucleotide sequence indicated a product of 388 amino acids with a molecular mass of 50.2 kda. this was in agreement with the molecular size estimated by gel electrophoresis. no significant dna ... | 1996 | 8588893 |
| production of caproic acid by cocultures of ruminal cellulolytic bacteria and clostridium kluyveri grown on cellulose and ethanol. | ruminal cellulolytic bacteria (fibrobacter succinogenes s85 or ruminococcus flavefaciens fd-1) were combined with the non-ruminal bacterium clostridium kluyveri and grown together on cellulose and ethanol. succinate and acetate produced by the cellulolytic organisms were converted to butyrate and caproate only when the culture medium was supplemented with ethanol. ethanol (244 mm) and butyrate (30 mm at ph 6.8) did not inhibit cellulose digestion or product formation by s85 or fd-1; however capr ... | 1995 | 8597554 |
| cloning, nucleotide sequence and expression of the gene encoding the cellulose-binding protein 1 (cbp1) of fibrobacter succinogenes s85. | the nucleotide sequence of the gene encoding the fibrobacter succinogenes s85 cellulose-binding protein 1 (cbp1) has been determined. the gene encodes a protein of 1054 amino acids with a molecular mass of 118614. the deduced amino acid sequence of cbp1 showed an extensive similarity to the cellulose-binding domain of an endoglucanase (egccd) from clostridium cellulolyticum and contained the reiterated regions. the cloned gene was inserted into an expression vector, prseta, and was expressed in ... | 1996 | 8647373 |
| interactions between fibrobacter succinogenes, prevotella ruminicola, and ruminococcus flavefaciens in the digestion of cellulose from forages. | the synergistic and inhibitory interactions observed between fibrobacter succinogenes a3c, prevotella ruminicola h2b, and ruminococcus flavefaciens b34b in the digestion of forage cellulose were studied in detail. orchardgrass and alfalfa hays, both at two maturity stages, were used as substrates. sequential inoculation procedures were developed whereby a second inoculation was made after the initial fermentation was killed. total cellulose digestion from sequential addition of the organisms was ... | 1996 | 8707727 |
| folding and stability of endoglucanase iii, a single-domain cellulase from trichoderma reesei. | the reversible folding of an endoglucanase (egiii) from the filamentous fungus trichoderma reesei was investigated by activity, tryptophan fluorescence, and peptide cd measurements. equilibrium stability was determined by urea denaturation at various ph and temperature values. unfolding and refolding rates were measured over a range of urea concentrations. the data from the equilibrium and kinetic studies fit a simple two-state model, except at lower urea concentrations, where the folding kineti ... | 1996 | 8784193 |
| inhibition by 1,10-phenanthroline of the breakdown of peptides by rumen bacteria and protozoa. | the rate of peptide breakdown in the rumen frequently exceeds the rate at which the amino acids released can be used for microbial growth. the final step in this often wasteful process involves the cleavage of dipeptides. the main rumen bacterial species with high dipeptidase activity, prevotella ruminicola, fibrobacter succinogenes, lachnospira multipara and megasphaera elsdenii, had activities which were inhibited > 95% by 1,10-phenanthroline, a chelator of divalent metal ions and metalloprote ... | 1996 | 8849644 |
| endoglucanase g from fibrobacter succinogenes s85 belongs to a class of enzymes characterized by a basic c-terminal domain. | a 3.6-kb fragment of the fibrobacter succinogenes s85 dna was sequenced and found to contain two open reading frames (orfs) on the same strand separated by 242 nucleotide bases. the translated protein from orf1 had a predicted mass of 52.3 kda. in a region of 320 amino acid overlap, it shares a 35% identity with the b-chain of the glutamate synthase of escherichia coli. the orf2 protein encodes a 519 residue protein designated celg. it consists of an orf of 1557 bp, encoding a polypeptide of 54. ... | 1996 | 8864216 |
| how many ruminal bacteria are there? | with the development of strictly anaerobic techniques and habitat-simulating media, a variety of bacteria were isolated from the rumen in the 1940s and 1950s. based on standard morphological and physiological characteristics, the microbial ecosystem of the rumen contains a very complex population of bacteria. in recent years, ruminal bacteria have been re-evaluated with newer, more objective, and genetically valid methods of classification. ribosomes are complicated structures, and their dna-enc ... | 1996 | 8880472 |
| why do many ruminal bacteria die and lyse so quickly? | studies using 15n have indicated that as much as 50% of the microbial mass turns over before n passes to the lower gut, and this n recycling significantly decreases the availability of microbial protein. protozoa digest bacteria and smaller protozoa, but bacterial protein can turn over even if protozoa are not present. fibrobacter succinogenes cultures lyse even when they are growing, and the lysis rate is independent of growth rate. when extracellular sugar is depleted, f. succinogenes secretes ... | 1996 | 8880474 |
| why don't ruminal bacteria digest cellulose faster? | the bacteria fibrobacter succinogenes, ruminococcus flavefaciens, and ruminococcus albus generally are regarded as the predominant cellulolytic microbes in the rumen. comparison of available data from the literature reveals that these bacteria are the most actively cellulolytic of all mesophilic organisms described to date from any habitat. in light of numerous proposals to improve microbial cellulose digestion in ruminants, it is instructive to examine the characteristics of these species that ... | 1996 | 8880475 |
| gene sequence analysis and properties of egc, a family e (9) endoglucanase from fibrobacter succinogenes bl2. | the endoglucanase gene (endc) of fibrobacter succinogenes bl2 encodes a protein of 620 amino acids (egc) that shows similarity with family e1 cellulases, and particularly with egb from f. succinogenes s85. alignment of the amino acid sequence of family e1 cellulases revealed that egc is composed of a n-terminal domain and a large catalytic domain of 453 residues containing an extension of 60 residues at its c-terminal part which is not present in other family e1 enzymes. egc shows the same subst ... | 1996 | 8919459 |
| detection of stratified microbial populations related to chlorobium and fibrobacter species in the atlantic and pacific oceans. | a gene lineage (sar406) related to chlorobium and fibrobacter species was found in 16s rrna gene clone libraries prepared from samples from two oceans. the clone libraries were constructed from total picoplankton genomic dna to assess bacterial diversity in the lower surface layer. the samples were collected by filtration from a depth of 80 m at a site in the western sargasso sea and from a depth of 120 m at a site in the pacific ocean, approximately 70 km from the oregon coast. the pcr and prim ... | 1996 | 8919778 |
| the effect of growth and starvation on the lysis of the ruminal cellulolytic bacterium fibrobacter succinogenes. | growing cultures of fibrobacter succinogenes assimilated more ammonia than could be accounted for by cellular protein, rna, or dna and released large amounts of nonammonia nitrogen. the difference between net and true growth was most dramatic at low dilution rates, but mathematical derivations indicated that the lysis rate was a growth rate-independent function. the lysis rate was sevenfold greater than the true maintenance rate (0.07 h-1 versus 0.01 h-1). because slowly growing cells had as muc ... | 1996 | 8919795 |
| simultaneous but differential metabolism of glucose and cellobiose in fibrobacter succinogenes cells, studied by in vivo 13c-nmr. | kinetics of [1-13c]glucose utilization were monitored by in vivo nmr spectroscopy on resting cells of fibrobacter succinogenes, in the presence of 32 mm [1-13c]glucose, 32 mm [1-13c]glucose and 64 mm unlabelled glucose, or 32 mm [1-13c]glucose and 32 mm unlabelled cellobiose. a similar production of acetate and succinate and a similar storage of glycogen were observed whatever the exogenous substrate. the presence of cellobiose or that of an equivalent amount of glucose did not reduce [1-13c]glu ... | 1996 | 8941985 |
| utilization of individual cellodextrins by three predominant ruminal cellulolytic bacteria. | growth of the ruminal bacteria fibrobacter succinogenes s85, ruminococcus flavefaciens fd-1, and r. albus 7 followed monod kinetics with respect to concentrations of individual pure cellodextrins (cellobiose, cellotriose, cellotetraose, cellopentaose, and cellohexaose). under the conditions tested, r. flavefaciens fd-1 possesses the greatest capacity to compete for low concentrations of these cellodextrins. | 1996 | 8975600 |
| a novel family 9 endoglucanase gene (celd), whose product cleaves substrates mainly to glucose, and its adjacent upstream homolog (cele) from fibrobacter succinogenes s85. | two adjacent, highly homologous endoglucanase genes, celd and cele from fibrobacter succinogenes s85, which were separated by an at-rich 223-nucleotide intergenic region were characterized. the celd gene codes for endoglucanase d (egd), a protein of 668 residues with a molecular mass of 71.7 kda, while the cele gene encodes endoglucanase e, a protein of 467 amino acids with a molecular mass of 50.7 kda. both gene products belong to family 9 of glycosyl hydrolases. egd displays an array of serine ... | 1996 | 8975618 |
| competition for cellulose among three predominant ruminal cellulolytic bacteria under substrate-excess and substrate-limited conditions. | three predominant ruminal cellulolytic bacteria (fibrobacter succinogenes s85, ruminococcus flavefaciens fd-1, and ruminococcus albus 7) were grown in different binary combinations to determine the outcome of competition in either cellulose-excess batch culture or in cellulose-limited continuous culture. relative populations of each species were estimated by using signature membrane-associated fatty acids and/or 16s rrna-targeted oligonucleotide probes. both f. succinogenes and r. flavefaciens c ... | 1997 | 9023950 |
| competition for cellobiose among three predominant ruminal cellulolytic bacteria under substrate-excess and substrate-limited conditions. | the ruminal cellulolytic bacteria ruminococcus flavefaciens fd-1 and fibrobacter succinogenes s85 coexisted in substrate-excess coculture with about equal population size, but r. flavefaciens outcompeted f. succinogenes for cellobiose in the substrate-limited cocultures whether the two strains were coinoculated or a steady-state culture of f. succinogenes was challenged by r. flavefaciens. this outcome of competition between these two strains is due to a classical pure and simple competition mec ... | 1997 | 9023951 |
| re-investigation of glucose metabolism in fibrobacter succinogenes, using nmr spectroscopy and enzymatic assays. evidence for pentose phosphates phosphoketolase and pyruvate formate lyase activities. | the glucose metabolism of fibrobacter succinogenes s85 was studied in detail; key intermediates and alternative pathways were evidenced by nmr and/or enzymatic assays. a high phosphoketolase activity was detected in four strains of fibrobacter under strictly anaerobic conditions, with ribose-5-phosphate as substrate, no activity was evidenced with fructose-6-phosphate. this is the first report of a pentose phosphates phosphoketolase in bacteria unable to use pentoses. in contrast, the entner-dou ... | 1997 | 9030201 |
| molecular beacons: trial of a fluorescence-based solution hybridization technique for ecological studies with ruminal bacteria. | molecular beacons are fluorescent probes developed for solution rather than membrane hybridization. we have investigated the utility of these probes to study rumen microbial ecology. two cellulolytic species, ruminococcus albus and fibrobacter succinogenes, were tested. membrane and solution hybridizations gave similar results in competition experiments with cocultures of r. albus 8 and f. succinogenes s85. | 1997 | 9055429 |
| bacterial diversity of a carolina bay as determined by 16s rrna gene analysis: confirmation of novel taxa. | carolina bays are naturally occurring shallow elliptical depressions largely fed by rain and shallow ground water. to identify members of the domain bacteria which inhibit such an environment, we used pcr to construct a library of 16s rrna genes (16s rdnas) cloned from dna extracted from the sediments of rainbow bay, located on the savannah river site, near aiken, s.c. oligonucleotides complementary to conserved regions of 16s rdna were used as primers for pcr, and gel-purified pcr products were ... | 1997 | 9097448 |
| an endoglucanase from the anaerobic fungus orpinomyces joyonii: characterization of the gene and its product. | an endoglucanase gene (cela) was isolated from a genomic library of the ruminal fungus orpinomyces joyonii. dna sequence analysis of cela revealed an intronless gene encoding a typical signal sequence, an n-terminal catalytic domain, two repeated regions linked by a short ser/thr-rich linker and a domain of unknown function. the deduced amino acid sequence of the catalytic domain showed homology with the family 5 cellulases. while the catalytic domain of cela was not homologous to the catalytic ... | 1997 | 9165703 |
| activity of h(+)-atpase in ruminal bacteria with special reference to acid tolerance. | batch culture experiments showed that permeabilized cells and membranes of ruminococcus albus and fibrobacter succinogenes, acid-intolerant celluloytic bacteria, have only one-fourth to one-fifth as much h(+)-atpase as megasphaera elsdenii and streptococcus bovis, which are relatively acid tolerant. even in the cells grown in continuous culture at ph 7.0, the acid-intolerant bacteria contained less than half as much h(+)-atpase as the acid-tolerant bacteria. the amounts of h(+)-atpase in the aci ... | 1997 | 9172333 |
| catalytic properties of the cellulose-binding endoglucanase f from fibrobacter succinogenes s85. | the celf gene from the predominant cellulolytic ruminal bacterium fibrobacter succinogenes encodes a 118.3-kda cellulose-binding endoglucanase, endoglucanase f (egf). this enzyme possesses an n-terminal cellulose-binding domain and a c-terminal catalytic domain. the purified catalytic domain displayed an activity profile typical of an endoglucanase, with high catalytic activity on carboxymethyl cellulose and barley beta-glucan. immunoblotting of egf and the formerly characterized endoglucanase 2 ... | 1997 | 9172367 |
| construction of a fibrobacter succinogenes genomic map and demonstration of diversity at the genomic level. | the genomic cleavage map of the type strain fibrobacter succinogenes s85 was constructed. the restriction enzymes asci, avrii, fsei, noti, and sfii generated dna fragments of suitable size distribution that could be resolved by pulsed-field gel electrophoresis (pfge). an average genome size of 3.6 mb was obtained by summing the total fragment sizes. the linkages between the 15 asci fragments of the genome were determined by combining two approaches: isolation of linking clones and cross-hybridiz ... | 1997 | 9175555 |
| competition between ruminal cellulolytic bacteria for adhesion to cellulose. | competition for adhesion to cellulose among the three main ruminal cellulolytic bacterial species was studied using differential radiolabeling (14c/3h) of cells. when added simultaneously to cellulose, ruminococcus flavefaciens fd1 and fibrobacter succinogenes s85 showed some competition; however, both species were surpassed competitively by ruminococcus albus 20. when r. flavefaciens fd1 and f. succinogenes s85 were already adherent, r. albus 20 adhesion occurred without inhibition but involved ... | 1997 | 9175559 |
| effects of a saccharomyces cerevisiae culture on ruminal bacteria that utilize lactate and digest cellulose. | the objective of this study was to determine the effects of a yeast (saccharomyces cerevisiae) culture on lactate utilization and cellulose digestion by ruminal bacteria. growth of selenomonas ruminantium hd4 in medium that contained 5 g/l of dl-lactate, trypticase, and yeast extract was stimulated 7 and 15% by 1 and 5% (vol/vol) yeast culture filtrate respectively. the 1 and 5% yeast culture filtrate stimulated growth of selenomonas ruminantium h18 and megasphaera elsdenii b159 and t81 on 5 g/l ... | 1997 | 9313145 |
| microbial perspective on fiber utilization by swine. | dietary fiber may contribute up to 30% of the maintenance energy needs of growing pigs. higher energy contributions may be obtained from dietary fiber fed to sows, along with some improvements in reproduction, health, and well-being. as long as cereal grain supplies and high-quality protein supplements are abundant, the use of fibrous feeds for swine most likely will be limited. however, as the human demand for cereal grains increases, swine producers, especially those with reproductive animals, ... | 1997 | 9331875 |
| production of a cell wall-specific monoclonal antibody to fibrobacter succinogenes. | a monoclonal antibody (mab) was raised against fibrobacter succinogenes and produced after fusion as ascites in balb/c mice. an elisa was used to test for specificity and sensitivity of the mab to detect f. succinogenes. the mab bd1 was tested for sensitivity and cross-reactivity in detecting f. succinogenes with elisa. the lower limits for f. succinogenes detection in pure and mixed culture-using mab bd1 with elisa was 10(5) cells ml-1. twenty-six other species of bacteria, including 12 cellulo ... | 1997 | 9351275 |
| production of succinate from glucose, cellobiose, and various cellulosic materials by the ruminal anaerobic bacteria fibrobacter succinogenes and ruminococcus flavefaciens. | the production of organic acids by two anaerobic ruminal bacteria fibrobacter succinogenes s85 and ruminococcus flavefaciens fd-1, was compared with glucose, cellobiose, microcrystalline cellulose, walseth cellulose (acid swollen cellulose), pulped paper, and steam-exploded yellow poplar as substrates. the major end product produced by f. succinogenes from each of these substrates was succinate (69.5-83%), the principal secondary product was acetate (16-30.5%). maximum succinate productivity ran ... | 1997 | 9373931 |
| [characteristics of the cellulolytic ruminal bacterium fibrobacter succinogenes and its attachment to cellulose]. | | 1997 | 9391322 |
| phylogenetic diversity of a bacterial community determined from siberian tundra soil dna. | genomic dna was isolated from the active layer of tundra soil collected from the kolyma lowland, northeast eurasia, near the arctic ocean coast. the ssu (small subunit) rrna genes were amplified with eubacterial primers from the bulk genomic community dna and cloned into plasmid vectors. forty-three ssu rdna clones were obtained, and all of them had different rflp patterns. phylogenetic analysis based on partial sequences (about 300 bp) established with the maximum likelihood method revealed the ... | 1997 | 9421915 |
| crystal structures and properties of de novo circularly permuted 1,3-1,4-beta-glucanases. | the 1,3-1,4-beta-glucanases from bacillus macerans and bacillus licheniformis, as well as related hybrid enzymes, are stable proteins comprised of one compact jellyroll domain. their structures are studied in an effort to reveal the degree of redundancy to which the three-dimensional structure of protein domains is encoded by the amino acid sequence. for the hybrid 1,3-1,4-beta-glucanase h(a16-m), it could be shown recently that a circular permutation of the sequence giving rise to the variant c ... | 1998 | 9489923 |
| an endo-1,4-beta-xylanase-encoding gene from agaricus bisporus is regulated by compost-specific factors. | compost is the preferred substrate for growth of the edible fungus agaricus bisporus. utilization of compost requires the production of enzymes involved in degradation of lignocellulolytic components. for molecular characterization of these processes we are isolating the encoding genes. by applying heterologous screening techniques, we have cloned such a gene, which is specifically induced on compost encoding an endo-1,4-beta-xylanase (xlna) belonging to glycosyl hydrolase family 10. the gene en ... | 1998 | 9514754 |
| effect of aspergillus oryzae extract alone or in combination with antimicrobial compounds on ruminal bacteria. | the effect of an aspergillus oryzae fermentation extract on the growth rates of pure cultures of ruminal bacteria was determined. bacteria were grown in an anaerobic ruminal fluid and carbohydrate medium. a sterile filtrate made with 10% a. oryzae was added to the medium at 2 or 5% (vol/vol) to provide a final a. oryzae concentration of 2 or 5 mg/ml, respectively. the filtrate had no effect on the growth rates of 10 of the 19 ruminal bacteria tested; however, the filtrate increased the growth ra ... | 1998 | 9684165 |
| strategies that ruminal bacteria use to handle excess carbohydrate. | when ruminal bacteria have insufficient nitrogen and other nutrients, excess carbohydrate can be toxic. pure cultures that are nitrogen-limited can convert only some of the excess carbohydrate to intracellular polysaccharide, but this pool can be quickly saturated. fibrobacter succinogenes cultures that have excess cellobiose secrete glucose and cellotriose into the culture medium, and prevotella ruminicola produces methylglyoxal, a highly toxic substance that causes a dramatic decrease in viabi ... | 1998 | 9690652 |
| news & notes: paper digestion by the cellulolytic ruminal bacterium fibrobacter succinogenes. | the objective of this study was to evaluate the ability of the predominant cellulolytic ruminal bacterium fibrobacter succinogenes s85 to digest filter paper, office paper, newspaper, and magazine paper. when f. succinogenes s85 was incubated with all four paper sources, little digestion of any paper occurred between 0 and 48 h. however, digestion of filter paper increased from 12% at 48 h to 80% at 120 h. no significant digestion of office paper, newspaper, or magazine paper occurred between 48 ... | 1998 | 9806983 |
| effect of diet on populations of three species of ruminal cellulolytic bacteria in lactating dairy cows. | the effects of four contrasting diets were determined on populations of three species of ruminal cellulolytic bacteria (ruminococcus albus, ruminococcus flavefaciens, and fibrobacter succinogenes) using oligonucleotide probes to rrna. diets based on alfalfa silage or corn silage as the primary fiber source were formulated to contain either 24 or 32% neutral detergent fiber measured after alpha-amylase treatment. the diets were fed twice daily to four ruminally fistulated, lactating holstein cows ... | 1999 | 10022014 |
| a cold-active glucanase from the ruminal bacterium fibrobacter succinogenes s85. | we previously characterized two endoglucanases, celg and egd, from the mesophilic ruminal anaerobe fibrobacter succinogenes s85. further comparative experiments have shown that celg is a cold-active enzyme whose catalytic properties are superior to those of several other intensively studied cold-active enzymes. it has a lower temperature optimum, of 25 degrees c, and retains about 70% of its maximum activity at 0 degrees c, while egd has a temperature optimum of 35 degrees c and retains only abo ... | 1999 | 10049853 |
| gc-ms analysis of diaminopimelic acid stereoisomers and amino acid enantiomers in rumen bacteria. | the amounts and the configuration of the stereoisomers of 2,6-diaminopimelic acid (dap) and the enantiomeric content of other amino acids were determined in five individual species (fibrobacter succinogenes, streptococcus bovis, selenomonas ruminantium, prevotella ruminicola and anaerovibrio lipolytica) of rumen bacteria, and in samples of mixed rumen bacteria isolated from sheep. the separation and quantification of the dap stereoisomers was achieved by gas chromatography (gc) of trifluoroacety ... | 1999 | 10191943 |
| effect of the addition of fumarate on methane production by ruminal microorganisms in vitro. | the effect of fumarate used as a feed additive on the reduction of methanogenesis in the rumen was evaluated by in vitro experiments. the addition of fumarate to the culture of mixed ruminal microorganisms that were fermenting hay powder and concentrate reduced methane production. most fumarate was metabolized to propionate, and a slight increase was noted in other volatile fatty acids. fumarate was utilized by mixed bacteria but not by mixed protozoa. fibrobacter succinogenes, selenomonas rumin ... | 1999 | 10212465 |
| interactions between carbon and nitrogen metabolism in fibrobacter succinogenes s85: a 1h and 13c nuclear magnetic resonance and enzymatic study. | the effect of the presence of ammonia on [1-13c]glucose metabolism in the rumen fibrolytic bacterium fibrobacter succinogenes s85 was studied by 13c and 1h nuclear magnetic resonance (nmr). ammonia halved the level of glycogen storage and increased the rate of glucose conversion into acetate and succinate 2.2-fold and 1.4-fold, respectively, reducing the succinate-to-acetate ratio. the 13c enrichment of succinate and acetate was precisely quantified by 13c-filtered spin-echo difference 1h-nmr sp ... | 1999 | 10223984 |