| ultrastructure and adhesion properties of ruminococcus albus. | morphological studies have shown that cells of the anaerobic rumen bacterium ruminococcus albus have electron-translucent granules of reserve carbohydrate in their cytoplasm, and that they have a polysaccharide "coat" layer external to their gram-negative cell wall. this coat layer, which stains specifically with ruthenium red, forms a compact mat of fibers adjacent to the cell, and fibrous elements also project as much as 0.6 mum from the cells. these radial fibers are clearly visualized by fre ... | 1975 | 47323 |
| partial purification of ferredoxin from ruminococcus albus and its role in pyruvate metabolism and reduction of nicotinamide adenine dinucleotide by h2. | extracts of ruminococcus albus were not able to convert pyruvate to acetyl phosphate, co2, and h2 after passage through a diethylaminoethyl (deae)-cellulose column. activity was restored by a brown protein fraction eluted from the column with 0.4 m cl-. the protein was partially purified and shown to have the spectral and biological characteristics of ferredoxin. r. albus ferredoxin, clostridium pasteurianum ferredoxin, and methyl viologen restored activity for pyruvate decomposition by deae-cel ... | 1977 | 195928 |
| the extracellular cellulases of ruminococcus albus. | | 1979 | 533152 |
| tetrahydrofolate and other growth requirements of certain strains of ruminococcus flavefaciens. | two strains of ruminococcus flavefaciens were studied. each grew in a chemically defined minimal medium containing: minerals; ammonium sulfate as a nitrogen source; amino acids as a nitrogen source, a growth promotant(s) or as both; cellobiose as an energy and carbon source; isobutyric acid, isovaleric acid, carbonic acid, and bicarbonate as additional carbon sources; and biotin, thiamine, and tetrahydrofolic acid as vitamins. tetrahydrofolic acid (5 ng/ml) served as a replacement for rumen flui ... | 1977 | 557955 |
| studies on some characteristics of hydrogen production by cell-free extracts of rumen anaerobic bacteria. | hydrogen production was studied in the following rumen anaerobes: bacteroides clostridiiformis, butyrivibrio fibrisolvens, enbacterium limosum, fusobacterium necrophorum, megasphaera elsdenii, ruminococcus albus, and ruminococcus flavefaciens. clostridium pasteurianum and escherichia coli were included for comparative purposes. hydrogen production from dithionite, dithionite-reduced methyl viologen, pyruvate, and formate was determined. all species tested produced hydrogen from dithionite-reduce ... | 1977 | 558042 |
| fermentation of cellulose by ruminococcus flavefaciens in the presence and absence of methanobacterium ruminantium. | the anaerobic cellulolytic rumen bacterium ruminococcus flavefaciens normally produces succinic acid as a major fermentation product together with acetic and formic acids, h2, and co2. when grown on cellulose and in the presence of the methanogenic rumen bacterium methanobacterium ruminantium, acetate was the major fermentation product; succinate was formed in small amounts; little formate was detected; h2 did not accumulate; and large amounts of ch4 were formed. m. ruminantium depends for growt ... | 1977 | 562131 |
| fermentation of mucins and plant polysaccharides by anaerobic bacteria from the human colon. | a total of 154 strains from 22 species of bifidobacterium, peptostreptococcus, lactobacillus, ruminococcus, coprococcus, eubacterium, and fusobacterium, which are present in high concentrations in the human colon, were surveyed for their ability to ferment 21 different complex carbohydrates. plant polysaccharides, including amylose, amylopectin, pectin, polygalacturonate, xylan, laminarin, guar gum, locust bean gum, gum ghatti, gum arabic, and gum tragacanth, were fermented by some strains from ... | 1977 | 563214 |
| effects of heavy metals and other trace elements on the fermentative activity of the rumen microflora and growth of functionally important rumen bacteria. | the inhibitory effects of high concentrations of essential and non-essential trace elements were tested on the rumen microflora using the rate of fermentation in vitro as the assay. the elements (and the concentration causing 50% inhibition) in decreasing order of toxicity were hg2+ (20 microgram/ml), cu2+ (21 microgram/ml), cr6+ (70 microgram/ml), se4+ (73 microgram/ml), ni2+ (160 microgram/ml), cd2+ (175 microgram/ml), as3+ (304 microgram/ml) and as5+ (1610 microgram/ml). the elements tested t ... | 1978 | 565671 |
| enumeration and isolation of anaerobic microbiota of piggery wastes. | media for enumeration of the microbiota of anaerobically stored piggery wastes were tested. highest colony counts were obtained with 80 to 100% farm slurry supernatant included in the anaerobic roll tube media. colony counts with these media numbered 2 x 10(9) to 12 x 10(9)/g (wet weight), which represents about 20% of the microscopic counts. lower percentages of slurry supernatant in the media gave lower colony counts. addition of glucose, cellobiose, and starch or of trypticase to media with 2 ... | 1978 | 566081 |
| adhesion of bacteroides succinogenes in pure culture and in the presence of ruminococcus flavefaciens to cell walls in leaves of perennial ryegrass (lolium perenne). | bacteroides succinogenes and ruminococcus flavefaciens are two of the most important cellulolytic bacteria in the rumen. adhesion of b. succinogenes in pure culture, and in mixed culture with r. flavefaciens, to the various types of cell walls in sections of perennial ryegrass (lolium perenne l. cultivar s24) leaves was examined by transmission and scanning electron microscopy. b. succinogenes adhered to the cut edges of most plant cell walls except those of the meta- and protoxylem. it also adh ... | 1978 | 567035 |
| [effect of methanosarcina on the growth of primary anaerobes]. | the effect of methanosarcina vacuolata on the mixed celluloytic population and on pure cultures of anaerobic bacteria was studied. in the pasteurized enrichment culture decomposing cellulose but producing no methane, the biomass of primary anaerobes increased at a higher rate when methanosarcina was introduced; the rate of cellulose hydrolysis did not change. methanosarcina stimulated also the growth of escherichia intermedia and ruminococcus albus on a medium containing glucose and cellobiose. ... | 1979 | 572903 |
| fermentations by saccharolytic intestinal bacteria. | most nonsporing anaerobes of the intestinal tract use the embden-meyerhof-parnas scheme to ferment carbohydrates. almost all of them oxidize pyruvate, the key fermentation intermediate, to acetyl coenzyme a and co2 with reduction of a low-potential electron acceptor. h2 is formed from the low potential acceptor or from nadh. pyruvate is a precursor of lactate, and phosphoenolpyruvate is a precursor of succinate and propionate. ethanol, acetate, and butyrate are formed from acetyl coenzyme a. for ... | 1979 | 760499 |
| urease assay and urease-producing species of anaerobes in the bovine rumen and human feces. | a growth medium and test were developed for rapid detection of urease in fermentative anaerobic bacteria. using nonselective rumen fluid roll-tube agar medium and the new test, it was confirmed that peptostreptococcus productus is often the most numerous urease-forming species in human feces. also, some fecal strains of ruminococcus albus, clostridium innocuum, and clostridium beijerinckii produced urease. single strains of fusobacterium prausnitzii, coprococcus catus, and streptococcus mitis th ... | 1977 | 879770 |
| cellulolytic cocci isolated from the cecum of guinea pigs (cavia porcellus). | five strains of anaerobic, gram-variable cellulolytic cocci, belonging to the genus ruminococcus, were isolated from the cecum of a guinea pig. they differed from most previously described strains of cellulolytic ruminococci as follows. (i) lactate was the major fermentation product; lesser amounts of formate and ethanol and a trace of succinate were also produced, along with an uptake of acetate. (ii) no growth occurred at 30 degrees c; however, good growth was observed at 38 and 45 degrees c, ... | 1977 | 879784 |
| the hydrogenation of unsaturated fatty acids by five bacterial isolates from the sheep rumen, including a new species. | five strictly anaerobic bacteria able to hydrogenate unsaturated fatty acids were isolated from sheep rumen. one was characterized as ruminococcus albus, two as eubacterium spp. and two as fusocillus spp., one of which is named as a new species. the fusocillus organisms were able to hydrogenate oleic acid and linoleic acid to stearic acid, and linolenic acid to cis-octadec-15-enoic acid. the r. albus and the two eubacteria did not hydrogenate oleic acid but converted linoleic and linolenic acids ... | 1975 | 1236930 |
| purification and properties of nadp-dependent glutamate dehydrogenase from ruminococcus flavefaciens fd-1. | glutamate dehydrogenase (gdh) (l-glutamate:nadp+ oxidoreductase, deaminating, ec 1.4.1.4) from the cellulolytic ruminal bacterium ruminococcus flavefaciens has been purified and characterized. the native enzyme and subunit are 280 and 48 kda, respectively, suggesting that the native enzyme is a hexamer. the enzyme requires 0.5 m kcl for optimal activity and has a ph optimum of 6.9 to 7.0. the kms for ammonia, alpha-ketoglutarate, and glutamate are 19, 0.41, and 62 mm, respectively. the sigmoidal ... | 1992 | 1335719 |
| 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 |
| homologous catalytic domains in a rumen fungal xylanase: evidence for gene duplication and prokaryotic origin. | a cdna (xyna), encoding xylanase a (xyla), was isolated from a cdna library, derived from mrna extracted from the rumen anaerobic fungus, neocallimastix patriciarum. recombinant xyla, purified from escherichia coli harbouring xyna, had a m(r) of 53,000 and hydrolysed oat-spelt xylan to xylobiose and xylose. the enzyme did not hydrolyse any cellulosic substrates. the nucleotide sequence of xyna revealed a single open reading frame of 1821 bp coding for a protein of m(r) 66,192. the predicted prim ... | 1992 | 1406248 |
| 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 |
| plasmid transformation of ruminococcus albus by means of high-voltage electroporation. | to apply recombinant dna techniques to the genetic manipulation of cellulolytic ruminal bacteria, a plasmid vector transformation system must be available. the objective of this work was to develop a system for plasmid transformation of ruminococcus albus. using high voltage electrotransformation, psc22 and pck17 plasmid vectors, derived from lactic acid bacteria plasmids and replicating via single-stranded dna intermediate, were successfully introduced into three freshly isolated r. albus strai ... | 1992 | 1426982 |
| the inhibition of fungal cellulolysis by cell-free preparations from ruminococci. | the degradation of filter paper by the anaerobic fungus neocallimastix frontalis strain re1 was reduced by the addition of cell-free supernates from cultures of ruminococcus albus strain j6 and r. flavefaciens strains 17 and 007. fungal uptake of, and growth on, glucose was not affected. after gel permeation and anion exchange chromatography, inhibitory activity towards fungal cellulolysis was recovered in a fraction from strain 17 that contained at least five negatively charged polypeptide comp ... | 1992 | 1427008 |
| response surface analysis of the effects of ph and dilution rate on ruminococcus flavefaciens fd-1 in cellulose-fed continuous culture. | the ruminal cellulolytic bacterium ruminococcus flavefaciens fd-1 was grown in cellulose-fed continuous culture with 20 different combinations of ph and dilution rate (d); the combinations were selected according to the physiological ph range of the organism (6.0 to 7.1) and growth rate of the organism on cellulose (0.017 to 0.10 h-1). a response surface analysis was used to characterize the effects of ph and d on the extent of cellulose consumption, growth yield, soluble sugar concentration, an ... | 1992 | 1514805 |
| partial characterization of a dna restriction endonuclease from ruminococcus flavefaciens fd-1 and its inhibition by site-specific adenine methylation. | the principal dna restriction-modification system of the cellulolytic ruminal bacterium ruminococcus flavefaciens fd-1 is described. the restriction endonuclease rflfi could be separated from cell extracts by phosphocellulose and heparin-sepharose chromatography. restriction enzyme digests utilizing rflfi alone or in combination with sali, a restriction enzyme isolated from streptomyces albus g, showed that the dna sequence recognized by rflfi either overlapped or was the same as that recognized ... | 1992 | 1539994 |
| partial purification and characterization of ral8i, a class-iis restriction endonuclease from ruminococcus albus 8 which recognizes 5'-ggatc. | heparin-agarose chromatography was used to isolate a restriction endonuclease (enase) from the cellulolytic gram+ anaerobe, ruminococcus albus 8. the enzyme, ral8i, was eluted from the column using 230-310 mm na+. however, the preparation was active only with dna substrates that were not dam-methylated. moreover, the restriction fragment pattern generated from simian virus 40 (sv40) dna was not consistent with the expected number of dam-methylation sites. alignment of the dam-methylation sites i ... | 1992 | 1547946 |
| a bifunctional xylanase encoded by the xyna gene of the rumen cellulolytic bacterium ruminococcus flavefaciens 17 comprises two dissimilar domains linked by an asparagine/glutamine-rich sequence. | the nucleotide sequence of the xyna gene of ruminococcus flavefaciens 17 was determined and found to consist of a 2862bp open reading frame beginning with a ttg start codon. the predicted product, xyla, consisted of distinct amino-terminal (a) and carboxy terminal (c) domains (248 amino acids, including a putative signal sequence, and 332 amino acids, respectively) linked by a repetitive sequence (b, 374 amino acids) extraordinarily rich in asparagine (45%) and glutamine (26%) residues. domains ... | 1992 | 1584021 |
| 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 |
| 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 |
| a survey of peptidase activity in rumen bacteria. | twenty-nine strains of 14 species of rumen bacteria were screened for their ability to hydrolyse ala2, ala5, glyarg-4-methoxy-2-naphthylamide (glyarg-mna) and leu-mna. several species, notably megasphaera elsdenii, were active against ala2, and a smaller number, including bacteroides ruminicola, butyrivibrio fibrisolvens, ruminococcus flavefaciens, lachnospira multipara and ruminobacter amylophilus, broke down ala5. streptococcus bovis had an exceptionally high leucine arylamidase activity. howe ... | 1991 | 1748877 |
| comparative in vitro activity of cefpodoxime against anaerobes other than bacteroides fragilis. | to assess the in vitro activity of cefpodoxime against anaerobic respiratory tract and oropharyngeal pathogens 77 strains belonging to 18 gram-negative and 7 gram-positive species were studied by means of agar dilution tests. for comparison cefuroxime, amoxicillin, amoxicillin + clavulanic acid and clindamycin were also tested. cefpodoxime was found to be active at concentrations of less than or equal to 0.125 mg/l against prevotella oralis, prevotella buccalis, prevotella bivia, porphyromonas a ... | 1991 | 1800380 |
| cloning of a beta-glucosidase gene from ruminococcus albus and its expression in escherichia coli. | a hindiii fragment of r. albus dna encoding beta-glucosidase was cloned into e. coli. the dna sequence (3158 bp) was determined, and the longest potential encoding sequence consisted of 2,841 bp (947 amino acids with the calculated molecular weight of 104,276. the deduced nh2-terminal amino acid sequence from the first (methionine) to the twentieth (glycine) was identical to that of the purified enzyme, suggesting that the gene for beta-glucosidase does not encode a signal peptide. the enzyme pu ... | 1991 | 1809203 |
| enhancing effects of bile salts on the degradation of glycosphingolipids by glycosidases from bacteria of the human fecal flora. | different concentrations of ionic and non-ionic detergents were examined for optimization of the in vitro degradations of intestinal glycosphingolipids by alpha- and beta-glycosidases from human fecal bacteria. in 5 mm triton x-100 the enzymes hydrolyzed glycosphingolipids with lactoseries type 1 and 2 chains essentially to lactosylceramide (laccer). in 5 mm sodium di- and trihydroxy bile salts lactosylceramide was degraded to glycosylceramide (glccer) in varying extent by enzymes from all five ... | 1991 | 1854798 |
| sequence of a cellulase gene from the rumen anaerobe ruminococcus flavefaciens 17. | a cellulase gene (enda) was isolated from a library of ruminococcus flavefaciens strain 17 dna fragments inserted in puc13. the enda product showed activity against acid-swollen cellulose, carboxymethyl-cellulose, lichenan, cellopentaose and cellotetraose, but showed no activity against cellotriose or binding to avicel. nucleotide sequencing indicated an encoded product of 455 amino acids which showed significant sequence similarity (ranging from 56% to 61%) with three endoglucanases from rumino ... | 1991 | 1886616 |
| isolation and properties of a (1,3)-beta-d-glucanase from ruminococcus flavefaciens. | a (1,3)-beta-d-glucanase [(1,3)-beta-d-glucan-3-glucanohydrolase] from ruminococcus flavefaciens grown on milled filter paper was purified 3,700-fold (19% yield) and appeared as a single major protein and activity band upon polyacrylamide gel electrophoresis. the enzyme did not hydrolyze 1,6-beta linkages (pustulan) or 1,3-beta linkages in glucans with frequent 1,6-beta-linkage branch points (scleroglucan). curdlan and carboxymethylpachyman were hydrolyzed at 50% the rate of laminarin. the enzym ... | 1991 | 1903625 |
| deantigenation of human erythrocytes by bacterial glycosidases--evidence for the noninvolvement of medium-sized glycosphingolipids in the dolichos biflorus lectin hemagglutination. | fresh human a1 erythrocytes, washed and pretreated in phosphate buffer with or without papain, were incubated at 37 degrees c with blood group-degrading enzymes from the human fecal ruminococcus torques strain ix-70. the effects were assayed as changes in hemagglutination patterns, and blood group activities of alkali stable glycolipid extracts from the enzyme-treated cells using dolichos biflorus anti-a1 lectin, ulex europaeus type 1 anti-h lectin, and various monoclonal anti-a antibodies. hemo ... | 1991 | 1929400 |
| characterization of hybrid proteins consisting of the catalytic domains of clostridium and ruminococcus endoglucanases, fused to pseudomonas non-catalytic cellulose-binding domains. | the n-terminal 160 or 267 residues of xylanase a from pseudomonas fluorescens subsp. cellulosa, containing a non-catalytic cellulose-binding domain (cbd), were fused to the n-terminus of the catalytic domain of endoglucanase e (ege') from clostridium thermocellum. a further hybrid enzyme was constructed consisting of the 347 n-terminal residues of xylanase c (xylc) from p. fluorescens subsp. cellulosa, which also constitutes a cbd, fused to the n-terminus of endoglucanase a (ega) from ruminococc ... | 1991 | 1953672 |
| modification of the properties of a ruminococcus albus endo-1,4-beta-glucanase by gene truncation. | an endo-1,4-beta-glucanase (egi) gene isolated from ruminococcus albus was deleted at the 5'-flanking region by gene truncation or at the 3'-flanking region by insertion of an omega (omega) fragment with a universal stop codon at the ecori or bamhi site. these modified genes were integrated into puc vectors to construct chimera plasmids for escherichia coli. the truncated egis were produced from transformants (e. coli) harboring the chimera plasmids. an egi with a 15-amino-acid n-terminal deleti ... | 1991 | 1987156 |
| degradation of wheat straw and alkaline hydrogen peroxide-treated wheat straw by ruminococcus albus 8 and ruminococcus flavefaciens fd-1. | degradation of wheat straw (ws) and alkaline hydrogen peroxide (ahp)-treated wheat straw (ahpws) by ruminococcus albus 8 and ruminococcus flavefaciens fd-1 was determined by measuring the growth (od600) of each bacterium and determining dm disappearance (dmd) of the substrate. complex medium and defined medium with or without the addition of phenylpropanoic acid (ppa) and phenylacetic acid (paa) were used. tubes were incubated at 39 degrees c for 8 d. both od600 and dmd indicated that ahpws was ... | 1991 | 2016208 |
| 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 and metabolism by ruminococcus flavefaciens. | the cellulolytic ruminal bacterium ruminococcus flavefaciens fd-1 utilizes cellobiose but not glucose as a substrate for growth. cellobiose uptake by r. flavefaciens fd-1 was measured under anaerobic conditions (n2), using [g-3h]cellobiose. the rate of cellobiose uptake for early- or late-log-phase cellobiose-grown cells was 9 nmol/min per mg of whole-cell protein. cellobiose uptake was inhibited by electron transport inhibitors, iron-reactive compounds, proton ionophores, sulfhydryl inhibitors, ... | 1991 | 2036021 |
| expression of two xylanase genes from the rumen cellulolytic bacterium ruminococcus flavefaciens 17 cloned in puc13. | two distinct xylanase genes (designated xyna and xynb) were subcloned in puc13 from non-homologous restriction fragments of ruminococcus flavefaciens 17 dna originally isolated in lambda embl3. the products of the two genes showed similar ph optima for hydrolysis of oat spelt xylan (around 5.5) and had little or no activity against carboxymethylcellulose. trace activities against p-nitrophenyl (pnp) cellobioside and pnp-xyloside were detected in clones containing xyna, but not in one harbouring ... | 1991 | 2045775 |
| modification of an endo-1,4-beta-glucanase from ruminococcus albus by gene truncation. | | 1990 | 2075980 |
| dna sequence of a beta-glucosidase from ruminococcus albus. | | 1990 | 2106673 |
| mode of action and substrate specificity of a purified exo-1,4-beta-d-glucosidase cloned from the cellulolytic bacterium ruminococcus albus ar67. | a gene encoding exo-1,4-beta-d-glucosidase, from ruminococcus albus ar67, was cloned in escherichia coli, restriction mapped, and shown to be expressed from sequences within the insert that function as a promoter in e. coli. the cloned enzyme was located predominantly in the cytoplasm (40%) and attached to insoluble cell components (48%). after purification to homogeneity, the enzyme (mr = 64,000, monomeric) was specific for substrates with beta-d-glucopyranosyl configuration and was inactive ag ... | 1990 | 2119579 |
| preservation of ruminal bacterium capsules by using lysine in the electron microscopy fixative. | ruminal bacteria from axenic cultures of ruminococcus flavefaciens fd1, butyrivibrio fibrisolvens 49, and bacterial types from the ruminal ecosystem that were fixed with 50 mm lysine (l-lysine hydrochloride) added to glutaraldehyde had better-preserved capsules and extracellular material than bacteria fixed without lysine. | 1990 | 2125818 |
| hydrophobic cluster analysis: procedures to derive structural and functional information from 2-d-representation of protein sequences. | hydrophobic cluster analysis (hca) [15] is a very efficient method to analyse and compare protein sequences. despite its effectiveness, this method is not widely used because it relies in part on the experience and training of the user. in this article, detailed guidelines as to the use of hca are presented and include discussions on: the definition of the hydrophobic clusters and their relationships with secondary and tertiary structures; the length of the clusters; the amino acid classificatio ... | 1990 | 2126461 |
| nucleotide sequence of the cela gene encoding a cellodextrinase of ruminococcus flavefaciens fd-1. | the nucleotide sequence of a 3.6 kb dna fragment containing a cellodextrinase gene (cela) from ruminococcus flavefaciens fd-1 was determined. the gene was expressed from its own regulatory region in escherichia coli and a putative consensus promoter sequence was identified upstream of a ribosome binding site and a ttg start codon. the complete amino acid sequence of the cela enzyme (352 residues) was deduced and showed no significant homology to cellulases from other organisms. two lysozyme-type ... | 1990 | 2129544 |
| detection of glycoproteins separated by nondenaturing polyacrylamide gel electrophoresis using the periodic acid-schiff stain. | we observed that published methods for staining glycoproteins in sodium dodecyl sulfate-polyacrylamide gels did not stain glycoproteins separated by nondenaturing polyacrylamide gel electrophoresis. therefore, the periodic acid-schiff stain for glycoprotein was adapted for use with proteins analyzed by nondenaturing polyacrylamide gel electrophoresis. following nondenaturing polyacrylamide gel electrophoresis proteins were denatured in situ by incubation with aqueous 2% sodium dodecyl sulfate, 5 ... | 1990 | 2196831 |
| nucleotide sequence of the ruminococcus albus sy3 endoglucanase genes cela and celb. | the complete nucleotide sequences of ruminococcus albus genes cela and celb coding for endoglucanase a (ega) and endoglucanase b (egb), respectively, have been determined. the cela structural gene consists of an open reading frame of 1095 bp. confirmation of the nucleotide sequence was obtained by comparing the predicted amino acid sequence with that derived by n-terminal analysis of purified ega. the celb structural gene consists of an open reading frame of 1227 bp; 7 bp upstream of the transla ... | 1990 | 2250649 |
| bacteria of the human intestinal microbiota produce glycosidases specific for lacto-series glycosphingolipids. | five strains of human fecal bacteria, of the ruminococcus and bifidobacterium genera, produce extracellular alpha- and beta-glycosidases that degrade intestinal mucin oligosaccharides and glycosphingolipids of the lacto-series type 1 chain. we have tested the activities and substrate specificities of these enzymes using para-nitrophenyl glycosides and glycosphingolipids of different core chains (lacto, neolacto, globo, isoglobo, galabio, and ganglio), carrying different blood group determinants ... | 1990 | 2277039 |
| the properties of forms of ruminococcus flavefaciens which differ in their ability to degrade cotton cellulose. | two mutant strains of ruminococcus flavefaciens strain 007 that differ in their ability to hydrolyse cotton fibres have been shown also to differ in their cell-surface topology, in that the cotton degrading form possessed larger and more protuberant cell surface structures. the strains had similar cmcase, cellobiosidase and beta-glucosidase activities. the results indicate the importance of cell-surface properties in cotton degradation by r. flavefaciens. | 1990 | 2283039 |
| cloning and sequencing of a bacteroides ruminicola b(1)4 endoglucanase gene. | bacteroides ruminicola b(1)4, a noncellulolytic rumen bacterium, produces an endoglucanase (carboxymethylcellulase [cmcase]) that is excreted into the culture supernatant. cultures grown on glucose, fructose, maltose, mannose, and cellobiose had high specific activities of cmcase (greater than 3 mmol of reducing sugar per mg of protein per min), but its synthesis was repressed by sucrose. b. rumincola did not grow on either ball-milled or acid-swollen cellulose even though the cmcase could hydro ... | 1990 | 2361940 |
| assessment of the endo-1,4-beta-glucanase components of ruminococcus flavefaciens fd-1. | the extracellular endo-1,4-beta-glucanase components of ruminococcus flavefaciens fd-1 were analyzed by high-performance liquid chromatography (hplc) by using deae ion-exchange, hydroxylapatite, and gel filtration chromatography and polyacrylamide gel electrophoresis (page). two endo-1,4-beta-glucanase peaks were resolved by deae-hplc and termed endoglucanases a and b. carboxymethyl cellulose (cmc) zymograms were achieved by enzyme separation using nondenaturing page followed by incubation of th ... | 1990 | 2383014 |
| metabolism of glycyrrhetic acid by rat liver microsomes: glycyrrhetinate dehydrogenase. | glycyrrhetic acid, derived from a main component of liquorice, was converted to 3-ketoglycyrrhetic acid reversibly by rat liver homogenates in the presence of nadph or nadp+. glycyrrhetic acid-oxidizing and 3-ketoglycyrrhetic acid-reducing activities were localized in microsomes among the subcellular fractions of rat liver. glycyrrhetic acid-oxidizing activity and 3-ketoglycyrrhetic acid-reducing activities showed ph optima at 6.3 and 8.5, respectively, and required nadp+ or nad+ and nadph or na ... | 1990 | 2405913 |
| inducible bacteriophages from ruminal bacteria. | the incidence of temperate bacteriophage in a wide range of ruminal bacteria was investigated by means of induction with mitomycin c. supernatant liquid from treated cultures was examined for phagelike particles by using transmission electron microscopy. of 38 ruminal bacteria studied, nine organisms (23.7%) representing five genera (eubacteria, bacteroides, butyrivibrio, ruminococcus, and streptococcus) produced phagelike particles. filamentous particles from butyrivibrio fibrisolvens are the f ... | 1989 | 2504111 |
| the isolation and comparison of cellulase genes from two strains of ruminococcus albus. | endo-1,4-beta-glucanase genes have been cloned from two strains of ruminococcus albus recently isolated in this laboratory. although the strains were phenotypically similar, cross-hybridization studies between them showed significant genetic differences, with only 20% of the genome forming dna heteroduplexes. heteroduplexes displayed an average dissociation temperature 9 degrees c lower than that of the homoduplex. consistent with this, restriction maps of the two endoglucanase genes showed no s ... | 1989 | 2600588 |
| degradation of barley straw, ryegrass, and alfalfa cell walls by clostridium longisporum and ruminococcus albus. | the recently isolated ruminal sporeforming cellulolytic anaerobe clostridium longisporum b6405 was examined for its ability to degrade barley straw, nonlignified cell walls (mesophyll and epidermis) and lignified cell walls (fiber) of ryegrass, and alfalfa cell walls in comparison with strains of ruminococcus albus. r. albus strains degraded 20 to 28% of the dry matter in barley straw in 10 days, while the clostridium degraded less than 2%. a combined inoculum of r. albus sy3 and strain b6405 wa ... | 1989 | 2619305 |
| structure of a ruminococcus albus endo-1,4-beta-glucanase gene. | a chromosomal dna fragment encoding an endo-1,4-beta-glucanase i (eg i) gene from ruminococcus albus cloned and expressed in escherichia coli with puc18 was fully sequenced by the dideoxy-chain termination method. the sequence contained a consensus promoter sequence and a structural amino acid sequence. the initial 43 amino acids of the protein were deduced to be a signal sequence, since they are missing in the mature protein (eg i). high homology was found when the amino acid sequence of the eg ... | 1989 | 2687251 |
| ruminal cellulolytic bacteria and protozoa from bison, cattle-bison hybrids, and cattle fed three alfalfa-corn diets. | ruminal cellulolytic bacteria and protozoa and in vitro digestibility of alfalfa fiber fractions were compared among bison, bison hybrids, and crossbed cattle (five each) when they were fed alfalfa and corn in a ratio of 100:0, 75:25, and 50:50, respectively. the total number of viable bacteria (2.16 x 10(9) to 5.44 x 10(9)/ml of ruminal fluid) and the number of cellulolytic bacteria (3.74 x 10(7) to 10.9 x 10(7)/ml) were not different among groups of animals fed each diet. the genera of protozo ... | 1989 | 2705767 |
| molecular cloning of genes from ruminococcus flavefaciens encoding xylanase and beta(1-3,1-4)glucanase activities. | clones expressing activity against xylan or beta(1-3,1-4)glucan (lichenan) were isolated from a library of ruminococcus flavefaciens 17 dna made in bacteriophage lambda embl3. hybridization analyses indicated the recovery of four separate genes encoding xylanases that showed no detectable associated carboxylmethylcellulase activity. one of these genes was associated with clones that also expressed beta(1-3,1-4)glucanase and beta-xylosidase activities. | 1989 | 2757382 |
| improved assay for quantitating adherence of ruminal bacteria to cellulose. | a quantitative technique suitable for the determination of adherence of ruminal bacteria to cellulose was developed. this technique employs adherence of cells to cellulose disks and alleviates the problem of nonspecific cell entrapment within cellulose particles. by using this technique, it was demonstrated that the adherence of ruminococcus flavefaciens fd1 to cellulose was inhibited by formaldehyde, methylcellulose, and carboxymethyl cellulose. adherence was unaffected by acid hydrolysates of ... | 1989 | 2782879 |
| cloning of the cellulase gene from ruminococcus albus and its expression in escherichia coli. | the gene for cellulase from ruminococcus albus f-40 was cloned in escherichia coli hb101 with pbr322. a 3.4-kilobase-pair hindiii fragment encoding cellulase hybridized with the chromosomal dna of r. albus. the ouchterlony double-fusion test gave a single precipitation line between the cloned enzyme and the cellulase from r. albus. the size of the cloned fragment was reduced by using hindiii and ecori. the resulting active fragment had a size of 1.9 kilobase pairs; and the restriction sites ecor ... | 1988 | 2843095 |
| seasonal changes in the cecal microflora of the high-arctic svalbard reindeer (rangifer tarandus platyrhynchus). | the dominant cecal bacteria in the high-arctic svalbard reindeer were characterized, their population densities were estimated, and cecal ph was determined in summer, when food quality and availability is good, and in winter, when it is very poor. in summer the total culturable viable bacterial population was (8.9 +/- 5.3) x 10(8) cells ml-1, whereas in winter it was (1.5 +/- 0.7) x 10(8) cells ml-1, representing a decrease to 17% of the summer population density. of the dominant species of cult ... | 1987 | 3030193 |
| influence of dietary fiber on xylanolytic and cellulolytic bacteria of adult pigs. | xylanolytic and cellulolytic bacteria were enumerated over an 86-day period from fecal samples of 10 8-month-old gilts that were fed either a control or a 40% alfalfa meal (high-fiber) diet. fecal samples were collected from all pigs on days 0, 3, 5, 12, 25, 37, 58, and 86. overall, the numbers of xylanolytic bacteria producing greater than 5-mm-diameter zones of clearing on 0.24% xylan roll tube medium after 24 to 36 h of incubation were 1.6 x 10(8) and 4.2 x 10(8)/g (dry weight) of feces for t ... | 1987 | 3030194 |
| activity of fiber-degrading microorganisms in the pig large intestine. | the large intestine is comparable to the rumen fermentation in many aspects; however, it is understood less well. fiber in the form of cellulose and hemicellulose is one of the major substrates fermented in the large intestine. various studies suggest that the pig can utilize fiber for growth, and up to 30% of its maintenance energy may be derived from volatile fatty acids produced in the large intestine. the total number of microorganisms in the pig large intestine do not change when a high fib ... | 1987 | 3040656 |
| purification and characterization of an exo-beta-1,4-glucanase from ruminococcus flavefaciens fd-1. | an exo-beta-1,4-glucanase (exo a) from ruminococcus flavefaciens fd-1 was purified to homogeneity and characterized. enzyme activity was monitored during purification by using the substrate p-nitrophenyl-beta-d-cellobioside (npc). over 85% of the npc activity was found to be extracellular once the filter paper was degraded (7 days). culture supernatant was harvested, and the protein was concentrated by ultrafiltration. the retentate (greater than or equal to 300,000 mr), containing most of the a ... | 1987 | 3115960 |
| fermentation of xylans by butyrivibrio fibrisolvens and other ruminal bacteria. | the ability of butyrivibrio fibrisolvens and other ruminal bacteria (6 species, 18 strains) to ferment a crude xylan from wheat straw or to ferment xylans from larchwood or oat spelts was studied. liquid cultures were monitored for carbohydrate utilization, cell growth (protein), and fermentation acid production. b. fibrisolvens 49, h17c, actf2, and d1 grew almost as well on one or more of the xylans as they did on cellobiose-maltose. b. fibrisolvens 12, r28, a38, x10c34, ard22a, and x6c61 exhib ... | 1987 | 3124741 |
| methylcellulose inhibition of exo-beta-1,4-glucanase a from ruminococcus flavefaciens fd-1. | a homogeneous preparation of exo-beta-1,4-glucanase a from ruminococcus flavefaciens fd-1 was competitively inhibited by low concentrations (less than 3 mm) of methylcellulose. the enzyme was also sensitive to the surfactant properties of methylcellulose at high methylcellulose concentrations. | 1988 | 3137869 |
| analysis of antibiotic susceptibility and extrachromosomal dna content of ruminococcus albus and ruminococcus flavefaciens. | seventeen ruminococcus albus and ruminococcus flavefaciens strains have been screened for naturally occurring antibiotic resistance, as determined by zones of inhibition from antibiotic disks. these strains were also examined for extrachromosomal dna content. all strains screened are resistant to low levels (10-200 micrograms/ml) of streptomycin. in contrast to the previously reported data, we have found that r. flavefaciens c-94 is now susceptible to both kanamycin and tetracycline. however, r. ... | 1988 | 3196962 |
| effect of the novel ionophore tetronasin (ici 139603) on ruminal microorganisms. | the antimicrobial activity of the novel ionophore tetronasin (formerly ici 139603) was compared with that of monensin for the growth of ruminal bacteria, protozoa, and an anaerobic fungus. the potency of tetronasin toward most bacteria and the fungus was an order of magnitude or more greater than that of monensin. lactobacillus casei was 55 times more sensitive to tetronasin than to monensin, indicating a potential role for tetronasin in reversing lactic acidosis. bacteria with a gram-positive u ... | 1988 | 3355139 |
| degradation of human intestinal glycosphingolipids by extracellular glycosidases from mucin-degrading bacteria of the human fecal flora. | certain normal strains of human fecal bacteria are unique in producing extracellular glycosidases that degrade the oligosaccharide chains of gut mucin glycoproteins. we have studied the action of such glycosidases partially purified from the cell-free supernates of five of these strains on intestinal glycosphingolipids isolated from human meconium. the glycolipids were sialosyl-lactosylceramide, lactosylceramide, and fucolipids with a, b, h, lea, or leb blood group determinants. in addition to t ... | 1988 | 3392043 |
| synergism of rumen microbial hydrolases during degradation of plant polymers. | in isolated mixture of exocellular enzymes of rumen bacteria ruminococcus flavefaciens, butyrivibrio fibrisolvens and rumen fungus neocallimastix frontalis, specific activities of cellulases, hemicellulases and glycosidases were determined. the highest specific activities were shown mostly for proteins of n. frontalis. | 1988 | 3397009 |
| enumeration and isolation of cellulolytic and hemicellulolytic bacteria from human feces. | the fibrolytic microbiota of the human large intestine was examined to determine the numbers and types of cellulolytic and hemicellulolytic bacteria present. fecal samples from each of five individuals contained bacteria capable of degrading the hydrated cellulose in spinach and in wheat straw pretreated with alkaline hydrogen peroxide (ahp-ws), whereas degradation of the relatively crystalline cellulose in whatman no. 1 filter paper (pmc) was detected for only one of the five samples. the mean ... | 1988 | 3415224 |
| effects of potassium ion concentrations on the antimicrobial activities of ionophores against ruminal anaerobes. | the antimicrobial activities of monensin and lasalocid against representative strains of ruminal bacteria were evaluated in medium containing three different concentrations of potassium (1.3, 7.9, or 23.3 mm). the growth of eubacterium ruminantium was inhibited by low concentrations of ionophores (less than or equal to 0.16 mg/liter), while the strain of streptococcus bovis tested was resistant to high concentrations of ionophores (40 mg/liter) at all potassium concentrations tested. the mics of ... | 1987 | 3426214 |
| 3 beta-hydroxysteroid dehydrogenase of ruminococcus sp. from human intestinal bacteria. | ruminococcus sp. po1-3 obtained from human intestinal flora is able to reduce dehydrocholate as well as 3-ketoglycyrrhetinate. from this bacterium dehydrocholate- and 3-ketoglycyrrhetinate-reducing activities were purified one thousand-fold together with 3-ketocholanate-reducing and 3-beta-hydroxyglycyrrhetinate (glycyrrhetic acid) oxidizing activities by means of matrex red a, sephadex g-200 and octyl-sepharose column chromatography. the purified enzyme catalyzed the reduction of dehydrocholic ... | 1986 | 3458705 |
| enzymes involved in the formation of 3 beta, 7 beta-dihydroxy-12-oxo-5 beta-cholanic acid from dehydrocholic acid by ruminococcus sp. obtained from human intestine. | ruminococcus sp. po1-3 from human intestinal flora reduced dehydrocholic acid to 3 beta-hydroxy-7,12-dioxo-5 beta-cholanic acid by means of the enzyme 3 beta-hydroxysteroid dehydrogenase (akao, t., akao, t., hattori, m., namba, t. and kobashi, k. (1986) j. biochem. (tokyo) 99, 1425-1431). this bacterium and its crude extract gave rise to another product, showing a lower rf value on tlc, from dehydrocholic acid. the product was identified as 3 beta, 7 beta-dihydroxy-12-oxo-5 beta-cholanic acid. t ... | 1987 | 3477291 |
| purification and characterization of 7 beta-hydroxysteroid dehydrogenase from ruminococcus sp. of human intestine. | 7 beta-hydroxysteroid dehydrogenase (7 beta-hsd) was produced by ruminococcus sp. po1-3 obtained from among human intestinal bacteria. the enzyme was purified from a crude extract by ammonium sulfate fractionation, and butyl-toyopearl 650m, sephadex g-150, matrex red a and octyl-sepharose chromatographies. the purified enzyme was obtained as a single band on polyacrylamide gel electrophoresis with enzyme activity staining and as one band corresponding to a molecular weight of 30,000 on sds-polya ... | 1987 | 3480890 |
| cloning and expression in escherichia coli of a cellulase gene from ruminococcus flavefaciens. | an endoglucanase gene of ruminococcus flavefaciens fd1 was cloned on the vector pecor251 to form the recombinant plasmid pmeb200. the cloned endoglucanase gene showed carboxymethylcellulase enzyme activity but no degradation of avicel (fmc corp., philadelphia, pa.) or filter paper. carboxymethylcellulase activity was found during the late-exponential-growth phase and accumulated in the periplasmic fraction. enzyme production was not subject to catabolite repression by glucose. | 1987 | 3549703 |
| interactions between treponema bryantii and cellulolytic bacteria in the in vitro degradation of straw cellulose. | to assess the contribution of individual bacterial species to the overall process of cellulose digestion in the rumen, cellulolytic bacteria (bacteroides succinogenes and ruminococcus albus) were tested as pure cultures and as cocultures with noncellulolytic treponema bryantii. in studies of in vitro barley straw digestion, treponema cocultures surpassed pure cultures of the cellulolytic organisms in dry matter disappearance, volatile fatty acid generation, and in the production of succinic acid ... | 1987 | 3567744 |
| electron microscopic study of the methylcellulose-mediated detachment of cellulolytic rumen bacteria from cellulose fibers. | the presence of methylcellulose prevents the attachment of cellulolytic rumen bacteria to cellulose fibers. the addition of methylcellulose to pure cultures of these organisms in which the cells are already adherent to cellulose causes their detachment from this insoluble substrate and the inhibition of their growth. methylcellulose is not used as a carbon source by these organisms and has no effect on their growth when glucose and cellobiose are the carbon sources. attached cells of bacteroides ... | 1987 | 3567745 |
| effect of phenolic monomers on ruminal bacteria. | ruminal bacteria were subjected to a series of phenolic compounds in various concentrations to acquire fundamental information on the influence on growth and the potential limits to forage utilization by phenolic monomers. ruminococcus albus 7, ruminococcus flavefaciens fd-1, butyrivibrio fibrisolvens 49, and lachnospira multiparus d-32 were tested against 1, 5, and 10 mm concentrations of sinapic acid, syringaldehyde, syringic acid, ferulic acid, vanillin, vanillic acid, p-coumaric acid, p-hydr ... | 1986 | 3789721 |
| isolation and properties of beta-glucosidase from ruminococcus albus. | an enzyme active against p-nitrophenyl-beta-d-glucoside was purified from logarithmic-phase cells of ruminococcus albus cultivated in a medium containing ball-milled cellulose. the purification yielded homogeneous enzyme after an approximately 520-fold increase in specific activity and a 9% yield. the enzyme was identified as a beta-glucosidase because it can hydrolyze cellobiose and cellooligosaccharides to glucose from the nonreducing ends. | 1985 | 3918007 |
| mucin degradation in human colon ecosystems. isolation and properties of fecal strains that degrade abh blood group antigens and oligosaccharides from mucin glycoproteins. | we previously reported that the oligosaccharide chains of hog gastric mucin were degraded by unidentified subpopulations numbering approximately 1% of normal human fecal bacteria. here we report on the enzyme-producing properties of five strains of mucin oligosaccharide chain-degrading bacteria isolated from feces of four healthy subjects. four were isolated from the greatest fecal dilutions yielding mucin side chain-degrading activity in culture, and thus were the numerically dominant side chai ... | 1985 | 3920248 |
| the effect of ammonia treatment on the solubilization of straw and the growth of cellulolytic rumen bacteria. | pre-treatment of straw with anhydrous ammonia increased its susceptibility to solubilization by the predominant cellulolytic bacteria from the rumen, bacteroides succinogenes, ruminococcus albus and r. flavefaciens. ammonia treatment also increased the production of microbial protein and fermentation products by all three species. scanning electron microscope observations of straw during digestion suggested that the attack of straw by these bacteria was accompanied by the formation of substantia ... | 1985 | 3997690 |
| antibiotic activity of an isocyanide metabolite of trichoderma hamatum against rumen bacteria. | a metabolite of trichoderma hamatum, 3-(3-isocyanocyclopent-2-enylidene)propionic acid, was tested for its effects on growth of and carbohydrate metabolism in 11 strains of functionally important rumen bacteria. to standardize the biological activity of this unstable metabolite, a rapid, aerobic disc diffusion assay was developed using escherichia coli atcc 11775. in an anaerobic broth dilution assay using a medium lacking rumen fluid and containing a soluble carbohydrate, the minimum inhibitory ... | 1985 | 4084861 |
| variations in enzyme activities of butyrivibrio fibrisolvens and ruminococcus albus grown in continuous culture. | | 1974 | 4275991 |
| glucose fermentation products in ruminococcus albus grown in continuous culture with vibrio succinogenes: changes caused by interspecies transfer of h 2 . | the influence of a h(2)-utilizing organism, vibrio succinogenes, on the fermentation of limiting amounts of glucose by a carbohydrate-fermenting, h(2)-producing organism, ruminococcus albus, was studied in continuous cultures. growth of v. succinogenes depended on the production of h(2) from glucose by r. albus. v. succinogenes used the h(2) produced by r. albus to obtain energy for growth by reducing fumarate in the medium. fumarate was not metabolized by r. albus alone. the only products detec ... | 1973 | 4351387 |
| enzymatic studies of pure cultures of rumen microorganisms. | joyner, a. e., jr. (university of california, davis), and r. l. baldwin. enzymatic studies of pure cultures of rumen microorganisms. j. bacteriol. 92:1321-1330. 1966.-the activities of enzymes representing the major pathways of carbohydrate metabolism and anaerobic electron transport in cell-free extracts of whole rumen contents have been reported. the effects of diet upon the activities of several enzymes suggested that enzymatic measurements might prove useful for the study of rumen metabolism ... | 1966 | 4380801 |
| nutritional features of the intestinal anaerobe ruminococcus bromii. | of six strains of ruminococcus bromii studied, five grew in a minimal chemically defined medium containing minerals, nh(4) (+) as nitrogen source, sulfide or sulfate as sulfur source, fructose as energy and carbon source, isobutyrate or 2-methylbutyrate and carbonic acid-bicarbonate as additional carbon sources, and the vitamins biotin, riboflavin, pyridoxine, vitamin b(12) (replaced by l-methionine), pantethine, and tetrahydrofolate. the strains also could utilize cysteine or thiosulfate but no ... | 1974 | 4451362 |
| fermentation of isolated pectin and pectin from intact forages by pure cultures of rumen bacteria. | studies on the rate and extent of galacturonic acid and isolated pectin digestion were carried out with nine strains of rumen bacteria (butyrivibrio fibrisolvens h10b and d16f, bacteroides ruminicola 23 and d31d, lachnospira multiparus d15d, peptostreptococcus sp. d43e, b. succinogenes a3c, ruminococcus flavefaciens b34b, and r. albus 7). only three strains, 23, d16f, and d31d, utilized galacturonic acid as a sole energy source, whereas all strains except a3c and h10b degraded (solubilized) and ... | 1972 | 4552890 |
| an anaerobic chemostat that permits the collection and measurement of fermentation gases. | a chemostat was designed to allow anaerobic growth in the culture vessel in the absence of a continuous stream of o(2)-free gas. produced gases were collected within the culture and collection vessels, and pressure build-up was prevented by allowing gases to expand into a collapsed football bladder. the culture overflow was collected in a flask, held at 0 c, that was emptied by applying a positive co(2) pressure to the system. ruminococcus albus, a h(2) and co(2)-producing anaerobe, was used to ... | 1973 | 4572986 |
| predominant gram-positive bacteria in human feces: numbers, variety, and persistence. | the predominant gram-positive bacteria in 47 fecal specimens from 10 healthy men were studied by microscopic and cultural counts, by the characterization and tentative identification of isolates, and by the use of fluorescein isothiocyanate (fitc)-conjugated globulins prepared using some of the isolates. gram-positive bacteria averaged 10(10.5+/-0.4(sd)/g (wet weight) of feces with significant variation from host to host. characterization of 865 isolates, all strict anaerobes and carbohydrate fe ... | 1974 | 4595760 |
| cellulose degradation by ruminococcus. | | 1973 | 4718899 |
| factors affecting cellulolysis by ruminococcus albus. | the factors influencing the digestion of pebble-milled cellulose by enzymes were studied by using several strains of ruminococcus albus including a mutant characterized by a more eccentric location of its colony in the clearing produced by digestion of the cellulose in the thin layer lining the wall of a culture tube. most of the cellulase is extracellular. as much as 65% of the cellulose could be digested by the cell-free enzymes provided the quantity of cellulose was small. fresh enzyme was re ... | 1973 | 4735890 |
| formation of hydrogen and formate by ruminococcus albus. | radioisotopic growth studies with specifically labeled (14)c-glucose confirmed that ruminococcus albus, strain 7, ferments glucose mainly by the embden-myerhof-parnas pathway to acetate, ethanol, formate, co(2), h(2), and an unidentified product. cell suspensions and extracts converted pyruvate to acetate, h(2), co(2), and a small amount of ethanol. formate was not produced from pyruvate and was not degraded to h(2) and co(2), indicating that formate was not an intermediate in the production of ... | 1973 | 4745433 |
| enzymes of intermediary metabolism of butyrivibrio fibrisolvens and ruminococcus albus grown under glucose limitation. | | 1973 | 4796347 |
| tryptophan biosynthesis from indole-3-acetic acid by anaerobic bacteria from the rumen. | microbes in ruminal contents incorporated (14)c into cells when they were incubated in vitro in the presence of [(14)c]carboxyl-labeled indole-3-acetic acid (iaa). most of the cellular (14)c was found to be in tryptophan from the protein fractions of the cells. pure cultures of several important ruminal species did not incorporate labeled iaa, but all four strains of ruminococcus albus tested utilized iaa for tryptophan synthesis. r. albus did not incorporate (14)c into tryptophan during growth ... | 1974 | 4855566 |
| regulation of cellulase from ruminococcus. | | 1972 | 5057390 |
| characteristics of ruminococcus and cellulolytic butyrivibrio species from the rumens of sheep fed differently supplemented teff (eragrostis tef) hay diets. | | 1970 | 5516604 |
| carbon dioxide requirement of various species of rumen bacteria. | the carbon dioxide requirement of 32 strains of rumen bacteria, representing 11 different species, was studied in detail. increasing concentrations of co(2) were added as nahco(3) to a specially prepared co(2)-free medium which was tubed and inoculated under nitrogen. prior depletion of co(2) in the inoculum was found to affect the level of requirement; however, the complexity and buffering capacity of the medium did not appear to be involved. an absolute requirement for co(2) was observed for e ... | 1971 | 5541030 |
| growth factor requirements of ruminococcus flavefaciens isolated from the rumen of cattle fed purified diets. | eight strains of cellulolytic cocci were isolated from a 10(-8) dilution of rumen ingesta and were presumptively identified as ruminococcus flavefaciens. four strains were isolated from a steer fed a purified diet which contained isolated soy protein, and four strains were isolated from a steer fed a purified diet which contained urea. certain growth factor requirements of these bacteria were determined. all strains grew with clarified rumen fluid added to the medium. however, fatty acids could ... | 1969 | 5785957 |