| characterization of wild-type and an active-site mutant in escherichia coli of short-chain acyl-coa dehydrogenase from megasphaera elsdenii. | the objective of this work is to determine the molecular mechanism and regulation of short-chain acyl-coa dehydrogenase (scad) from megasphaera elsdenii. to achieve this, the gene coding for scad from m. elsdenii was cloned and sequenced. site-directed mutagenesis was then used to identify an amino acid residue that is required for the proposed mechanism. to clone the gene, the amino acid sequence of the 50 n-terminal residues of scad from m. elsdenii was determined. this sequence information wa ... | 1993 | 8399220 |
| flavin dynamics in reduced flavodoxins. a time-resolved polarized fluorescence study. | the time-resolved fluorescence and fluorescence anisotropy characteristics of reduced flavin mononucleotide in solution as well as bound in flavodoxins isolated from the bacteria desulfovibrio gigas, desulfovibrio vulgaris, clostridium beijerinckii mp and megasphaera elsdenii have been examined. all fluorescence and fluorescence anisotropy decays were analyzed by two different methods: (a) least-squares fitting with a sum of exponentials and (b) the maximum entropy method to yield distributed li ... | 1993 | 8425547 |
| presence of lactate dehydrogenase and lactate racemase in megasphaera elsdenii grown on glucose or lactate. | activity of d-lactate dehydrogenase (d-ldh) was shown not only in cell extracts from megasphaera elsdenii grown on dl-lactate, but also in cell extracts from glucose-grown cells, although glucose-grown cells contained approximately half as much d-ldh as dl-lactate-grown cells. this indicates that the d-ldh of m. elsdenii is a constitutive enzyme. however, lactate racemase (lr) activity was present in dl-lactate-grown cells, but was not detected in glucose-grown cells, suggesting that lr is induc ... | 1993 | 8439152 |
| intrinsic crotonase activity in a bacterial butyryl-coa dehydrogenase. | butyryl-coa, crotonyl-coa or 3-hydroxybutyryl-coa all ultimately form an enzyme-acetoacetyl-coa complex upon aerobic addition to butyryl-coa dehydrogenase purified from megasphaera elsdenii, implying the presence of crotonase activity. this behaviour remains even after treatment with 6m urea, which destroys the activity of the main crotonase fraction from m. elsdenii. flavin-sensitised photoinactivation destroys residual crotonase and dehydrogenase activities in parallel. butyryl-coa dehydrogena ... | 1993 | 8490573 |
| purification and partial characterisation of the e14k mutant of flavodoxin from megasphaera elsdenii. | | 1996 | 8674684 |
| 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 |
| 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 |
| 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 |
| phytase activity of anaerobic ruminal bacteria. | phytase catalyses the release of phosphate from phytate (myo-inositol hexakisphosphate), the predominant form of phosphorus in cereal grains, oilseeds and legumes. the presence of phytase activity was investigated in 334 strains of 22 species of obligately anaerobic ruminal bacteria. measurable activities were demonstrated in strains of selenomonas ruminantium, megasphaera elsdenii, prevotella ruminicola, mitsuokella multiacidus and treponema spp. strains isolated from fermentations with cereal ... | 1998 | 9639927 |
| oxidase activity of the acyl-coa dehydrogenases. | the medium chain acyl-coa dehydrogenase catalyzes the flavin-dependent oxidation of a variety of acyl-coa thioesters with the transfer of reducing equivalents to electron-transferring flavoprotein. the binding of normal substrates profoundly suppresses the reactivity of the reduced enzyme toward molecular oxygen, whereas the oxidase reaction becomes significant using thioesters such as indolepropionyl-coa (ip-coa) and 4-(dimethylamino)-3-phenylpropionyl-coa (dp-coa). steady-state and stopped-flo ... | 1998 | 9671517 |
| cloning and analysis of the genes for a novel electron-transferring flavoprotein from megasphaera elsdenii. expression and characterization of the recombinant protein. | the genes that encode the two different subunits of the novel electron-transferring flavoprotein (etf) from megasphaera elsdenii were identified by screening a partial genomic dna library with a probe that was generated by amplification of genomic sequences using the polymerase chain reaction. the cloned genes are arranged in tandem with the coding sequence for the beta-subunit in the position 5' to the alpha-subunit coding sequence. amino acid sequence analysis of the two subunits revealed that ... | 1998 | 9694853 |
| electron-transferring flavoprotein from megasphaera elsdenii; gene organisation and structural information. | | 1998 | 9765933 |
| ph-dependent spectroscopic changes associated with the hydroquinone of fmn in flavodoxins. | photoreduction with a 5-deazaflavin as the catalyst was used to convert flavodoxins from desulfovibrio vulgaris, megasphaera elsdenii, anabaena pcc 7119, and azotobacter vinelandii to their hydroquinone forms. the optical spectra of the fully reduced flavodoxins were found to vary with ph in the ph range of 5.0-8.5. the changes correspond to apparent pka values of 6.5 and 5.8 for flavodoxins from d. vulgaris and m. elsdenii, respectively, values that are similar to the apparent pka values report ... | 1999 | 10090764 |
| the ability of "low g + c gram-positive" ruminal bacteria to resist monensin and counteract potassium depletion. | gram-negative ruminal bacteria with an outer membrane are generally more resistant to the feed additive, monensin, than gram-positive species, but some bacteria can adapt and increase their resistance. 16s rrna sequencing indicates that a variety of ruminal bacteria are found in the "low g + c gram-positive group," but some of these bacteria are monensin resistant and were previously described as gram-negative species (e.g., selenomonas ruminantium and megasphaera elsdenii). the activity of mone ... | 1999 | 10486059 |
| characterization of the gene encoding the [fe]-hydrogenase from megasphaera elsdenii. | the gene encoding the [fe]-hydrogenase from the anaerobic bacterium megasphaera elsdenii has been cloned and sequenced. the gene is monocistronic, in keeping with the protein being a monomer. the translated protein sequence (484 residues, m(r)=53 kda) comprises a small 2[4fe-4s] ferredoxin-like domain and a large domain containing the catalytic site. comparisons with other [fe]-hydrogenase sequences, including two of which the crystal structures are known, show that the m. elsdenii protein is am ... | 2000 | 10669801 |
| restriction and modification systems of ruminal bacteria. | a high frequency of type ii restriction endonuclease activities was detected in selenomonas ruminantium but not in other rumen bacteria tested. eight different restriction endonucleases were characterized in 17 strains coming from genetically homogeneous local population. chromosomal dna isolated from s. ruminantium strains was found to be refractory to cleavage by various restriction enzymes, implying the presence of methylase activities additional to those required for protection against the c ... | 2001 | 11501482 |
| modeling of growth, lactate consumption, and volatile fatty acid production by megasphaera elsdenii cultivated in minimal and complex media. | use of the pirt and luedeking-piret equations permits the determination of the effect of medium composition on the metabolic patterns of megasphaera elsdenii grown in minimal and complex media with lactate as the major carbon source. to establish the significance of the parameters involved in the pirt and luedeking-piret equations, a quantitative statistical criterion was proposed. in the complex medium, lactate was completely used for growth and product formation, whereas in the minimal medium ... | 2002 | 11934285 |
| enumeration of megasphaera elsdenii in rumen contents by real-time taq nuclease assay. | to develop a real-time taq nuclease assay (tna) to enable the in vivo enumeration of megasphaera elsdenii. | 2002 | 11966917 |
| the enrichment of a ruminal bacterium (megasphaera elsdenii yj-4) that produces the trans-10, cis-12 isomer of conjugated linoleic acid. | to isolate predominant ruminal bacteria that produce trans-10, cis-12 conjugated linoleic acid (cla) from linoleic acid (la). | 2002 | 11972704 |
| stimulation of butyrate production by gluconic acid in batch culture of pig cecal digesta and identification of butyrate-producing bacteria. | gluconic acid reaches the large intestine to stimulate lactic acid bacteria. however, the fermentation pattern of gluconic acid has yet to be elucidated. accordingly, we examined the fermentation properties induced by gluconic acid in the pig cecal digesta in vitro. we also tested sorbitol and glucose, substrates for which the fermentation rate and patterns are known. the gluconic acid-utilizing bacteria were further isolated from pig cecal digesta and identified to examine the effect of gluconi ... | 2002 | 12163667 |
| amino acid deamination by ruminal megasphaera elsdenii strains. | when ruminal fluid from a cow fed timothy hay was serially diluted (10-fold increments into anaerobic broth containing 15 mg ml(-1) trypticase), the low dilutions (< or =10(-6)) had optical densities greater than 2.0 and ammonia concentrations greater than 100 m m. the optical densities and ammonia concentrations of the 10(-8) and 10(-9) dilutions were very low, but large cocci were observed in the 10(-8) dilution. the large cocci were isolated and identified by 16s rdna sequencing as megasphaer ... | 2002 | 12232664 |
| diet influences the ecology of lactic acid bacteria and escherichia coli along the digestive tract of cattle: neural networks and 16s rdna. | in this manuscript, the authors have sought to gain a better understanding of the interactions between escherichia coli and lactic acid bacteria (lab) isolated from rogossa mrs agar along the digestive tract of grain- and forage-fed cattle. e. coli from cattle receiving a high-grain diet were more numerous (p<0.05) than from the high-forage diet and the highest numbers were in the faeces. isolates on rogossa mrs agar were always greater in the high-grain diet (p<0.05) and contained a significant ... | 2003 | 12576580 |
| allisonella histaminiformans gen. nov., sp. nov. a novel bacterium that produces histamine, utilizes histidine as its sole energy source, and could play a role in bovine and equine laminitis. | when cattle and horses are fed large amounts of grain, histamine can accumulate in the gastrointestinal tract, and this accumulation can cause an acute inflammation of the hooves (laminitis). when ruminal fluid from dairy cattle fed grain supplements was serially diluted in anaerobic mrs medium containing histidine (50 mm), histamine was detected at dilutions as high as 10(-7). the histidine enrichments were then transferred successively in an anaerobic, carbonate-based medium (50 mm histidine) ... | 2002 | 12583709 |
| 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 |
| identification of a putative histidine base and of a non-protein nitrogen ligand in the active site of fe-hydrogenases by one-dimensional and two-dimensional electron spin-echo envelope-modulation spectroscopy. | the active h-cluster of the fe-hydrogenases from megasphaera elsdenii and desulfovibrio vulgaris (strain hildenborough) has been investigated with one- and two-dimensional pulsed epr spectroscopy. in both complexes the coordination of a nitrogen-containing ligand was found. the unusual quadrupole interaction parameters (d. vulgaris: quadrupole coupling constant, k = 1.20 mhz, asymmetry parameter eta = 0.32, m. elsdenii: k = 1.23 mhz, eta = 0.25) indicate a non-protein type of nitrogen and are co ... | 1997 | 9346288 |
| isolation of tetracycline-resistant megasphaera elsdenii strains with novel mosaic gene combinations of tet(o) and tet(w) from swine. | anaerobic bacteria insensitive to chlortetracycline (64 to 256 microg/ml) were isolated from cecal contents and cecal tissues of swine fed or not fed chlortetracycline. a nutritionally complex, rumen fluid-based medium was used for culturing the bacteria. eight of 84 isolates from seven different animals were identified as megasphaera elsdenii strains based on their large-coccus morphology, rapid growth on lactate, and 16s ribosomal dna sequence similarities with m. elsdenii lc-1(t). all eight s ... | 2003 | 12839756 |
| establishing populations of megasphaera elsdenii ye 34 and butyrivibrio fibrisolvens ye 44 in the rumen of cattle fed high grain diets. | to determine whether megasphaera elsdenii ye34 (lactic acid degrader) and butyrivibrio fibrisolvens ye44 (alternative starch utilizer to streptococcus bovis) establish viable populations in the rumen of beef cattle rapidly changed from a forage-based to a grain-based diet. | 2003 | 12911711 |
| [metabolism of rumen microbial populations formed on biosubstrates with different assimilation under the effect of pentachlorophenol]. | it has been established that metabolism of mixed microbial population formed on easy assimilated sources of energy and nitrogen (concentrate diet) progressed on higher level. there is increase of amilolytic activity, formation of lactate, ammonia, low molecular carbonic acids with predomination of propionate molar fraction. the increased resistance to effect of pentachlorophenol (pcp) is characteristic nature of the latter. the role of the most resistant synthrophic bacteria to pcp increases. th ... | 2002 | 12916235 |
| bacterial changes in the rumen during the onset of feed-lot bloat of cattle and characteristics of peptostreptococcus elsdenii n. sp. | | 1959 | 13617940 |
| the fermentation of lactate and acrylate by the rumen micro-organism lc. | | 1959 | 13628579 |
| [contribution to the study of the biosynthesis of fatty acids. ii. fermentation of lactic acid c-2 by peptostreptococcus elsdenii]. | | 1963 | 14079882 |
| [about the systematic classification of peptostreptococcus elsdenii]. | | 1963 | 14089092 |
| electron transport in peptostreptococcus elsdenii. | | 1964 | 14269334 |
| lactate metabolism by peptostreptococcus elsdenii: evidence for lactyl coenzyme a dehydrase. | | 1965 | 14292829 |
| the breakdown of pyruvate by cell-free extracts of the rumen micro-organism lc. | | 1960 | 14431361 |
| megasphaera elsdenii jcm1772t normalizes hyperlactate production in the large intestine of fructooligosaccharide-fed rats by stimulating butyrate production. | hyperlactate production is related to disorders of the large intestine such as inflammatory bowel diseases. lactate, an intermediate in hindgut fermentation, is metabolized to scfa. megasphaera elsdenii can convert lactate to butyrate, a physiologically important organic acid for the hindgut mucosa. this experiment was conducted to determine whether m. elsdenii normalizes hyperlactate production and stimulates butyrate production in the rat large intestine. specific pathogen-free sprague-dawley ... | 2003 | 14519808 |
| purification of electron-transferring flavoprotein from megasphaera elsdenii and binding of additional fad with an unusual absorption spectrum. | electron-transferring flavoprotein (etf), its redox partner flavoproteins, i.e., d-lactate dehydrogenase and butyryl-coa dehydrogenase, and another well-known flavoprotein, flavodoxin, were purified from the same starting cell paste of an anaerobic bacterium, megasphaera elsdenii. the purified etf contained one mol fad/mol etf as the sole non-protein component and bound almost one mol of additional fad. this preparation is a better subject for investigations of m. elsdenii etf than the previousl ... | 2003 | 14688238 |
| diverse tetracycline resistance genotypes of megasphaera elsdenii strains selectively cultured from swine feces. | a total of 30 megasphaera elsdenii strains, selectively isolated from the feces of organically raised swine by using me109 m medium, and one bovine strain were analyzed for tetracycline resistance genotypic and phenotypic traits. tetracycline-resistant strains carried tet(o), tet(w), or a tet gene mosaic of tet(o) and tet(w). m. elsdenii strains carrying tet(owo) genes exhibited the highest tetracycline mics (128 to >256 microg/ml), suggesting that tet(o)-tet(w) mosaic genes provide the selectiv ... | 2004 | 15184185 |
| direct electrochemistry of megasphaera elsdenii iron hydrogenase. definition of the enzyme's catalytic operating potential and quantitation of the catalytic behaviour over a continuous potential range. | the fe-hydrogenase from megasphaera elsdenii undergoes direct electron exchange with glassy carbon electrodes. cyclic voltammetry defines the catalytic-performance of the enzyme over a continuous but precisely defined range of potentials. in the presence of h2 and protons the bias of the enzyme towards h2 production is readily visualised. variation of the response with ph indicates that protein ionisations with pk of approximately 6.7 and 8.3 regulate the catalytic activity. possible origins for ... | 1997 | 9128731 |
| gatc-specific restriction--modification systems in ruminal bacteria. | the gatc-specific restriction and modification activities were analyzed in 11 major bacterial representatives of ruminal microflora. modification phenotype was observed in 13 out of 40 ruminal strains. mboi isoschizomeric restriction endonucleases were detected in 10 bacterial strains tested; three strains lacked any detectable corresponding endonuclease activity. the only examined strain of mitsuokella multi-acida was found to possess a different type of endonuclease activity. this is the first ... | 2004 | 15227796 |
| microbial monitoring by molecular tools of a two-phase anaerobic bioreactor treating fruit and vegetable wastes. | microbial consortia in a two-phase, anaerobic bioreactor using a mixture of fruit and vegetable wastes were established. bacterial and archaeal communities obtained by a culture-independent approach based on single strand conformation polymorphism analysis of total 16s rdna showed the adaptation of the microflora to the process parameters. throughout the 90 d of the study, the species composition of the bacterial community changed significantly. bacterial 16s rdna showed at least 7 different maj ... | 2004 | 15269562 |
| influence of dipeptidyl peptidase inhibitors on growth, peptidase activity, and ammonia production by ruminal microorganisms. | the aim was to investigate known and potential new inhibitiors of dipeptidyl peptidases (dpp) for their effects on ruminal microorganisms. gly-phe diazomethylketone (gpd), ala-ala chloromethylketone (aac), benserazide (dl-serine 2-(2,3,4- trihydroxybenzyl) hydrazide), and diprotin a (ile-pro-ile) inhibited dpp activities of prevotella albensis, p. ruminicola, p. bryantii, p. brevis, and mixed ruminal microorganisms, though incompletely and, except for diprotin a, without absolute specificity for ... | 2004 | 15297916 |
| crystallization and preliminary x-ray crystallographic analysis of the electron-transferring flavoprotein from megasphaera elsdenii. | electron-transferring flavoprotein from the rumen bacterium megasphaera elsdenii is a heterodimer (m(r) = 75 kda) containing fad as cofactor and functioning solely to mediate electron transfer between the prosthetic groups of other proteins. the enzyme was crystallized by the hanging-drop vapour-diffusion method using polyethylene glycol 4000 as precipitant. the crystals obtained belong to the space group p2(1)2(1)2(1) with unit-cell dimensions of a = 58.75, b = 61.77 and c = 122.27 a. interesti ... | 1997 | 15299914 |
| protozoa involved in butyric rather than lactic fermentative pattern during latent acidosis in sheep. | we used six ruminally cannulated texel wethers to study the relative role of protozoa and lactate-metabolizing bacteria in ruminal fermentative patterns during an induced latent acidosis. the sheep were fed an alfalfa hay diet (h) and latent acidosis was induced, following a short transition period of one week, with a grain-rich acidotic diet (w, 60% wheat + 40% alfalfa hay). ruminal ph, ruminal volatile fatty acids (vfa), lactate and nh3 concentrations, protozoa and lactate-utilizing bacterial ... | 2004 | 15460159 |
| characterization of a cytoplasmic reserve glucan from ruminococcus albus. | ruminococcus albus, an anaerobic bacterium that digests cellulose in the rumen of cattle, produces intracellular polysaccharide granules varying from 0.05 to 0.31 mum in diameter when grown in batch culture. this polysaccharide material was purified and found to contain d-glucose as the only reducing sugar. the polyglucose polymer was slightly opalescent in aqueous solution and formed a strong reddish purple iodine complex with a maximum absorbance at 550 nm. its infrared spectrum had characteri ... | 1977 | 16345231 |
| comparison of substrate affinities among several rumen bacteria: a possible determinant of rumen bacterial competition. | five rumen bacteria, selenomonas ruminantium, bacteroides ruminicola, megasphaera elsdenii, streptococcus bovis, and butyrivibrio fibrisolvens were grown in continuous culture. estimates of substrate affinities were derived from lineweaver-burk plots of dilution rate versus substrate concentration. each bacterium was grown on at least four of the six substrates: glucose, maltose, sucrose, cellobiose, xylose, and lactate. wide variations in substrate affinities were seen among the substrates util ... | 1979 | 16345358 |
| comparison of maintenance energy expenditures and growth yields among several rumen bacteria grown on continuous culture. | maintenance energy expenditures were mesured for five rumen bacteria, selenomonas ruminantium, butyrivibrio fibrisolvens, bacteroides ruminicola, megasphaera elsdenii, and streptococcus bovis, by using a complex medium with glucose as the carbon source. large differences (as high as 8.5-fold) in maintenance energy expenditures were seen among these bacteria. the suggestion is made that maintenance requirements could be a significant determinant of bacterial competition in the rumen. theoretical ... | 1979 | 16345359 |
| effects of combinations of substrates on maximum growth rates of several rumen bacteria. | five rumen bacteria, selenomonas ruminantium, bacteroides ruminicola, megasphaera elsdenii, butyrivibrio fibrisolvens, and streptococcus bovis were grown in media containing nonlimiting concentrations of glucose, sucrose, maltose, cellobiose, xylose and/or lactate. each bacterium was grown with every substrate that it could ferment in every possible two-way combination. only once did a combination of substrates result in a higher maximum growth rate than that observed with either substrate alone ... | 1979 | 16345360 |
| nutritional interdependence among rumen bacteria, bacteroides amylophilus, megasphaera elsdenii, and ruminococcus albus. | nutritional interdependence among three representatives of rumen bacteria, bacteroides amylophilus, megasphaera elsdenii, and ruminococcus albus, was studied with a basal medium consisting of minerals, vitamins, cysteine hydrochloride, and nh(4). b. amylophilus grew well in the basal medium supplemented with starch and produced branched-chain amino acids after growth ceased. when cocultured with b. amylophilus in the basal medium supplemented with starch and glucose, amino acid-dependent m. elsd ... | 1980 | 16345608 |
| rumen bacterial competition in continuous culture: streptococcus bovis versus megasphaera elsdenii. | streptococcus bovis and megasphaera elsdenii were grown in continuous culture with maltose as the limiting substrate at dilution rates of 0.36, 0.22, and 0.12 h. after each steady-state turnover, the ph was decreased by adding concentrated hcl to the medium reservoir. relative counts of the two species at each dilution rate indicated that when the ph was high (6.6 to 6.0), higher dilution rates selected for a higher ratio of s. bovis to m. elsdenii. at intermediate ph (6.0 to 5.4), higher diluti ... | 1981 | 16345793 |
| role of megasphaera elsdenii in the fermentation of dl-[2-c]lactate in the rumen of dairy cattle. | since megasphaera elsdenii ferments a variable part of dl-lactate to butyrate, measurement of the percentage of dl-lactate fermented to propionate via the acrylate pathway in rumen contents will underestimate the participation of m. elsdenii in the dl-lactate fermentation. the percentage of dl-[2-c]lactate fermented via the acrylate pathway and the percentage of dl-lactate fermented to butyrate can be measured with c-ft (fourier transform)-nuclear magnetic resonance. on the average, the contribu ... | 1981 | 16345862 |
| enrichment and isolation of rumen bacteria that reduce trans- aconitic acid to tricarballylic acid. | bacteria from the bovine rumen capable of reducing trans-aconitate to tricarballylate were enriched in an anaerobic chemostat containing rumen fluid medium and aconitate. after 9 days at a dilution rate of 0.07 h, the medium was diluted and plated in an anaerobic glove box. three types of isolates were obtained from the plates (a crescent-shaped organism, a pleomorphic rod, and a spiral-shaped organism), and all three produced tricarballylate in batch cultures that contained glucose and trans-ac ... | 1985 | 16346691 |
| catabolism of amino acids by megasphaera elsdenii lc1. | the amino acids in an acid hydrolysate of casein were catabolized more extensively by megasphaera elsdenii than those in an enzymic hydrolysate. threonine and serine were most actively degraded, but no resultant increase in growth yield occurred. branched-chain volatile fatty acid production, which increased as the dilution rate of a glucose-limited chemostat decreased, seemed to be associated with maintenance rather than with growth. | 1986 | 16347061 |
| effects of a strain of saccharomyces cerevisiae (levucell sc1), a microbial additive for ruminants, on lactate metabolism in vitro. | the effect of levucell sc, a strain of saccharomyces cerevisiae marked as a feed additive for ruminants, was investigated in vitro on lactate metabolism by the ruminal bacteria streptococcus bovis and megasphaera elsdenii. the coculture between 10(7) live cells x ml(-1) of sc and a streptococcus bovis strain in the presence of glucose reduced lactate production by the bacterial strain. live yeast cells were able to compete with streptococcus bovis for glucose utilization in strictly anaerobic co ... | 1996 | 8864215 |
| limited genetic variability in megasphaera elsdenii strains. | levels of phenotypic and genotypic diversity among seven megasphaera elsdenii strains recovered from rumen contents of cattle, sheep and lambs were determined by a combination of antibiotic-resistance analysis and pcr fingerprint techniques targeted both to the ribosomal rna operon (ardra, risa) and the whole genome (eric-pcr, rapd-pcr). despite exhibiting different antibiotic resistance profiles, the tested strains represent genetically nearly identical isolates. close genetic relatedness was f ... | 2006 | 17007430 |
| dominance of prevotella and low abundance of classical ruminal bacterial species in the bovine rumen revealed by relative quantification real-time pcr. | relative quantification real-time pcr was used to quantify several bacterial species in ruminal samples from two lactating cows, each sampled 3 h after feeding on two successive days. abundance of each target taxon was calculated as a fraction of the total 16s rrna gene copies in the samples, using taxon-specific and eubacterial domain-level primers. bacterial populations showed a clear predominance of members of the genus prevotella, which comprised 42% to 60% of the bacterial rrna gene copies ... | 2007 | 17235560 |
| 13c-n.m.r. of the cyanylated apoflavodoxin and flavodoxin from clostridium pasteurianum. | the thiol group of the flavodoxin from clostridium pasteurianum has been cyanylated in a single step using [cyanato-13c]2-nitro-5-thiocyanatobenzoic acid. this chemical modification increases the dissociation constant of the apoflavodoxin-fmn complex 10-fold from 0.33 +/- 0.15 nm to 2.9 +/- 1.3 nm. the thiocyanate carbons of the cyanylated cysteine residue of apoflavodoxin and flavodoxin had chemical shift values of 114.7 and 112.3 p.p.m. respectively. from these chemical shifts we conclude that ... | 1993 | 8363575 |
| increased amount of bifidobacterium thermacidophilum and megasphaera elsdenii in the colonic microbiota of pigs fed a swine dysentery preventive diet containing chicory roots and sweet lupine. | to investigate which specific bacterial species that were stimulated or inhibited in the proximal colon of pigs when a fructan-rich diet was compared with a diet that contained resistant carbohydrates. the study focussed especially on bifidobacterial species by using a noncultureable approach. | 2007 | 17953596 |
| monensin has no effect on growth and metabolism of megasphaera elsdenii. | a rumen strain of megasphaera elsdenii was grown on glucose and lactate in monensin-free and monensin-supplemented medium (10 mg/l). monensin had no effect on growth rate, growth yields, metabolic pattern and composition of cells. growth yields of dry matter and protein were higher in cultures supplied with glucose than in cultures supplied with lactate. the bacterium compensated the lower gain of energy from fermentation of lactate by rapid utilization of this substrate. cells grown on glucose ... | 1993 | 8262448 |
| effect of monensin feeding and withdrawal on populations of individual bacterial species in the rumen of lactating dairy cows fed high-starch rations. | real-time polymerase chain reaction (pcr) was used to quantify 16 procaryotic taxa in the rumina of two lactating dairy cows following supply and subsequent withdrawal of the feed additive monensin (13.9 mg/kg of diet dry matter) in a high-starch, silage-based ration. pcr was conducted on dna from rumen samples collected 6 h post feeding on two successive days before monensin supplementation, after 30 days of monensin supplementation, and at six weekly intervals after monensin withdrawal. mean v ... | 2008 | 18535825 |
| biotransformation of 2,4,6-trinitrotoluene by pure culture ruminal bacteria. | twenty-one ruminal bacteria species were tested for their ability to degrade 2,4,6-trinitrotoluene (tnt) within 24 h. butyrivibrio fibrisolvens, fibrobacter succinogenes, lactobacillus vitulinus, selenomonas ruminantium, streptococcus caprinus, and succinivibrio dextrinosolvens were able to completely degrade 100 mg/l tnt, with <5% of the original tnt recovered as diaminonitrotoluene metabolites. eubacterium ruminantium, lactobacillus ruminis, ruminobacter amylophilus, streptococcus bovis, and w ... | 2009 | 18839246 |
| effects of an aspergillus oryzae fermentation extract and other factors on lactate utilization by the ruminal bacterium megasphaera elsdenii. | the objective of this study was to determine the effects of an aspergillus oryzae fermentation extract (amaferm) as well as other factors on lactate utilization by the ruminal bacterium megasphaera elsdenii b159. addition of amaferm or a filter-sterilized amaferm filtrate stimulated l-lactate uptake by both m. elsdenii and the ruminal selenomonad strain h18. growth of m. elsdenii in medium that contained dl-lactate (2 g/l), trypticase, and yeast extract was only slightly stimulated by the additi ... | 1993 | 8226379 |
| oxidation-reduction properties of short-chain acyl-coa dehydrogenase: effects of substrate analogs. | redox potentials of short-chain acyl-coa dehydrogenase from the anaerobe, megasphaera elsdenii, have been determined by means of uv-visible spectroelectrochemistry in the presence of substrate analogs. during redox titrations in the presence of 2-azabutyryl-coa, up to 85% anionic fad semiquinone was stabilized with a molar absorbance at 387 nm of 19 mm-1 cm-1. despite a slow reduction of short-chain acyl-coa dehydrogenase by 2-azabutyryl-coa (< 2% reduction/h), a dissociation constant of 0.7 mic ... | 1994 | 8080271 |
| production of 2-aminobutyrate by megasphaera elsdenii. | production of the amino acid 2-aminobutyrate was studied in four strains of megasphaera elsdenii grown on a lactate-based growth medium containing bacto-casamino acids and yeast extract. supplementation with threonine increased the production of 2-aminobutyrate in three of the four strains, but no substantial increase in production was noted with serine, methionine, or aspartate, all of which are potential sources for the precursor of 2-aminobutyrate, 2-oxobutyrate. l-cycloserine, an inhibitor o ... | 1994 | 8069781 |
| rumen microbiome composition determined using two nutritional models of subacute ruminal acidosis. | subacute ruminal acidosis (sara) is a metabolic disease in dairy cattle that occurs during early and mid-lactation and has traditionally been characterized by low rumen ph, but lactic acid does not accumulate as in acute lactic acid acidosis. it is hypothesized that factors such as increased gut permeability, bacterial lipopolysaccharides, and inflammatory responses may have a role in the etiology of sara. however, little is known about the nature of the rumen microbiome during sara. in this stu ... | 2009 | 19783747 |
| product binding modulates the thermodynamic properties of a megasphaera elsdenii short-chain acyl-coa dehydrogenase active-site mutant. | previous work has shown that the redox properties of megasphaera elsdenii short-chain acyl-coa dehydrogenase (scad) are specifically modulated upon the binding of the substrate/product couple, allowing the reaction to proceed thermodynamically [stankovich, m.t., & soltysik, s. (1987) biochemistry 26, 2627-2632]. the focus of this study on the glu367gln scad mutant protein is to gain an understanding of this phenomenon. the active-site mutant glu367gln scad inactivates the reductive and oxidative ... | 1994 | 8003473 |
| the constitutive nature of alkaline phosphatase in rumen bacteria. | alkaline phosphatase (apase) activity of megasphaera elsdenii was enhanced by po4 2- limitation in batch culture; however, six other species of rumen bacteria tested showed no increase in apase activity under these conditions. alkaline phosphatase was produced by the mixed rumen microflora even though the inorganic phosphorus concentration was as high as 10mm. the apase activity of the bacterial fraction from rumen fluid was not increased during incubation in a phosphorus-free culture medium. si ... | 1980 | 7407707 |
| oral administration of lactobacillus plantarum lq80 and megasphaera elsdenii inp-001 induces efficient recovery from mucosal atrophy in the small and the large intestines of weaning piglets. | weaning causes atrophy of intestinal mucosa and a drop of iga protection in piglets which increases vulnerability to pathogenic infections. probiotic lactobacilli may support recovery from such weaning stresses. butyrate-produce bacteria may support the growth of colonic mucosa. megasphaera elsdenii, a lactate-utilizing butyrate producer, may help butyrate production particularly when combined with lactobacilli. weaned piglets (experiment 1: 20 days old, experiment 2: 28 days old) were orally do ... | 2009 | 20163663 |
| utilization of amino acids by bacteria from the pig small intestine. | this study determined the utilization of amino acids (aa) by bacteria from the lumen of the pig small intestine. digesta samples from different segments of the small intestine were inoculated into media containing 10 mmol/l each of select aa (l-lysine, l-threonine, l-arginine, l-glutamate, l-histidine, l-leucine, l-isoleucine, l-valine, l-proline, l-methionine, l-phenylalanine or l-tryptophan) and incubated for 24 h. the previous 24-h culture served as an inoculum for a subsequent 24-h subcultur ... | 2010 | 20300787 |
| effects of hops (humulus lupulus l.) extract on volatile fatty acid production by rumen bacteria. | to determine the effects of hops extract on in vitro volatile fatty acid (vfa) production by bovine rumen micro-organisms. | 2010 | 20456526 |
| lactate dehydrogenase gene variability among predominant lactate utilizing ruminal bacteria. | the inter- and intraspecies variability of lactate dehydrogenase (ldh) gene was determined among the predominant ruminal lactate utilizing bacteria. nearly complete nucleotide sequences of ldh gene, encoding nad-dependent lactate dehydrogenase of three megasphaera elsdenii and six selenomonas ruminantium strains, were obtained and compared. phylogenetic analyses revealed a limited variability between the ldh sequences studied. the majority of differences observed were silent mutations at the 3rd ... | 2010 | 20680561 |
| rumen microbial population dynamics during adaptation to a high-grain diet. | high-grain adaptation programs are widely used with feedlot cattle to balance enhanced growth performance against the risk of acidosis. this adaptation to a high-grain diet from a high-forage diet is known to change the rumen microbial population structure and help establish a stable microbial population within the rumen. therefore, to evaluate bacterial population dynamics during adaptation to a high-grain diet, 4 ruminally cannulated beef steers were adapted to a high-grain diet using a step-u ... | 2010 | 20851965 |
| a 13c nuclear-magnetic-resonance study on free flavins and megasphaera elsdenii and azotobacter vinelandii flavodoxin. 13c-enriched flavins as probes for the study of flavoprotein active sites. | | 1981 | 7308219 |
| effect of ruminal pulse dose of polyunsaturated fatty acids on ruminal microbial populations and duodenal flow and milk profiles of fatty acids. | the objective of this study was to examine the effect of ruminal pulse dose of free linoleic acid (la) and free docosahexaenoic acid (dha) on microbial populations in the rumen, duodenal fatty acid (fa) flow, milk composition, and milk fa profiles of chinese holstein dairy cows. four rumen- and duodenal-fistulated chinese holstein cows in mid lactation (138.5±10d in milk) were randomly assigned to 3 treatment groups and 1 control group in a 4×4 latin square design over 4 periods (3 wk per period ... | 2011 | 21605768 |
| effects of monolaurin on ruminal methanogens and selected bacterial species from cattle, as determined with the rumen simulation technique. | before being able to implement effective ruminal methane mitigation strategies via feed supplementation, the assessment of side effects on ruminal fermentation and rumen microbial populations is indispensable. in this respect we investigated the effects of monolaurin, a methane-mitigating lipid, on methanogens and important carbohydrate-degrading bacteria present in ruminal fluid of dairy cattle in continuous culture employing the rumen simulation technique. in six experimental runs, each lastin ... | 2011 | 21787874 |
| the persistence of antibiotic resistance: evaluation of a probiotic approach using antibiotic-sensitive megasphaera elsdenii strains to prevent colonization of swine by antibiotic-resistant strains. | megasphaera elsdenii is a lactate-fermenting, obligately anaerobic bacterium commonly present in the gastrointestinal tracts of mammals, including humans. swine m. elsdenii strains were previously shown to have high levels of tetracycline resistance (mic = 64- >256 ++g/ml) and to carry mosaic (recombinant) tetracycline resistance genes. baby pigs inherit intestinal microbiota from the mother sow. in these investigations we addressed two questions. when do m. elsdenii strains from the sow coloniz ... | 2011 | 21821757 |
| chlortetracycline-resistant intestinal bacteria in organically-raised and feral swine. | organically-raised swine had high fecal populations of chlortetracycline (ctc)-resistant (growing at 64 ++g ctc/ml) escherichia coli, megasphaera elsdenii and anaerobic bacteria. by comparison, ctc-resistant bacteria in feral swine feces were over 1000-fold fewer and exhibited lower taxonomic diversity. | 2011 | 21821750 |
| changes in ruminal bacterial community composition following feeding of alfalfa ensiled with a lactic acid bacterial inoculant. | some silage inoculants help to improve silage quality and promote an increase in milk production, possibly through altering the rumen microflora. we hypothesized that rumen bacterial community composition (bcc) would be different in cows fed alfalfa ensiled with the inoculant lactobacillus plantarum mtd/1 (lp) compared with those fed alfalfa ensiled without the inoculant (ctrl). eight ruminally cannulated holstein cows were allotted to 2 diets (ctrl or lp) in a double crossover design with four ... | 2012 | 22192212 |
| The complex vaginal flora of West African women with bacterial vaginosis. | The spectrum of bacteria associated with bacterial vaginosis (BV) has recently expanded through taxonomic changes and the use of molecular methods. These methods have yet to be used in large-scale epidemiological studies in Africa where BV is highly prevalent. | 2011 | 21949860 |
| mechanism of action of butyryl-coa dehydrogenase: reactions with acetylenic, olefinic, and fluorinated substrate analogues. | the acetylenic thio ester (3-pentynoyl)pantetheine irreversibly inactivates butyryl-coa dehydrogenase from megasphaera elsdenii. the inactivator becomes covalently attached to the protein (0.61 +/- 0.1 mol of 14c-labeled inactivator/mol of enzyme flavin). no modification of the flavin cofactor is seen. the covalent enzyme-inactivator adduct is labile toward base and neutral hydroxylamine. these treatments release 85 +/- 5% of the incorporated 14c label from the protein. base-catalyzed hydrolysis ... | 1982 | 7159554 |
| structural and dynamic information on the complex of megasphaera elsdenii apoflavodoxin and riboflavin 5'-phosphate. a phosphorus-31 nuclear magnetic resonance study. | it is shown that commercial fmn contains a considerable amount of the 4', 3', and 2' isomers and other phosphorus-containing compounds. these impurities can easily be analyzed and quantified by the 31p nmr technique. the phosphate group of fmn bound to megasphaera elsdenii apoflavodoxin is probably in the dianionic form. its chemical shift is almost independent of ph in the range 5.5-9.2 and of the redox state of the protein. the phosphate group of bound fmn is buried in the protein. protons of ... | 1982 | 7074025 |
| regulation of lactate metabolism in the rumen. | the regulation of lactic acid production, the regulation of lactate fermentation and the role of lactate as intermediate in the rumen metabolism was studied. the ph had a pronounced effect on all three processes and therefore buffer capacity of the rumen contents is also described. starch gave much less rise to lactic acidosis than soluble sugars, as glucose and fructose. most bacteria grow faster and therefore produce more lactic acid when amino acids and/or soluble proteins are present in the ... | 1981 | 7048723 |
| role of dl-lactic acid as an intermediate in rumen metabolism of dairy cows. | the role of dl-lactic acid as an intermediate in the rumen of a friesian x holstein dairy cow adapted to a diet of hay ad libitum plus 12 kg of a concentrate mixture was studied in vitro and in vivo. concentrations of soluble sugars in the rumen fluid became maximal at 30 min postfeeding, but at 90 min no sugars were detectable. the dl-lactate concentration increased very rapidly to about 30 mm at 30 min after feeding, whereas the maximum total vfa concentration was reached 15 min later. more th ... | 1983 | 6863168 |
| effects of a combination of hinokitiol (β-thujaplicin) and an organic acid mixture on ruminal fermentation in heifers fed a high-grain diet. | this study evaluated the effects of hinokitiol (a natural antibacterial compound extracted from thujopsis dolabrata var. hondai) and an organic acid mixture (citrate content 50%) on ruminal fermentation. antibacterial properties were examined by measuring minimal inhibitory concentration. hinokitiol at 1.56 µg/ml or an organic acid mixture at 1600 µg/ml inhibited streptococcus bovis growth. the combination of 0.78 µg/ml hinokitiol and 200 µg/ml of an organic acid mixture also inhibited s. bovis ... | 2012 | 22250737 |
| raman spectra of flavin bound in flavodoxins and in other flavoproteins. evidence for structural variations in the flavin-binding region. | the resonance coherent anti-stokes raman scattering (cars) spectra for a number of flavoproteins are found to be fingerprints for the particular type of flavoprotein. one group studied were the bacterial flavodoxins: desulfovibrio vulgaris, desulfovibrio desulfuricans, azotobacter vinelandii, megasphaera elsdenii, clostridium kluyverii and clostridium formicoaceticum. the other examples were the enzymes lactate monooxygenase and glucose oxidase. fmn complexed to vibrio harveyi luciferase, and a ... | 1983 | 6840072 |
| [visual field changes in mesopic and scotopic conditions using friedmann visual field analyser. iii. acquired chorioretinal diseases (author's transl)]. | | 2005 | 546186 |
| butyryl-coa dehydrogenase from megasphaera elsdenii. specificity of the catalytic reaction. | the absorption coefficient of butyryl-coa dehydrogenase from megasphaera elsdenii at 450 nm is determined as 14.4 mm-1 x cm-1 in the coa-free form and 14.2 mm-1 x cm-1 in the coa-liganded form (both yellow). the latter value is considerably higher than the earlier published estimate. phenazine ethosulphate offers great advantages over phenazine methosulphate as a coupling dye in the catalytic assay despite giving lower vmax. values (506 min-1 as compared with 1250 min-1 under the conditions used ... | 1984 | 6712628 |
| letter: bromide intoxication. | | 2002 | 126712 |
| [gelatineous drop-like dystrophy of the cornea: little-known primary localized amyloidosis]. | | 2012 | 3497732 |
| [alterations of drinking water quality due to bacterial re-contamination]. | | 2012 | 4154628 |
| [hypertensive angiopathy of the brain]. | cerebral vessels were studied by light microscopy in 20 autopsies after hemorrhagic stroke from arterial hypertension. primary (acute), secondary (reparative) changes, as well as changes reflecting compensatory-adaptive processes, were found in the intracerebral and superficial arteries of the brain. the whole complex of these vascular changes was defined as hypertonic angiopathy. the usage of such terms as "angiopathy" and "combined angiopathy" were discussed. criteria of morphologic diagnosis ... | 2013 | 3827621 |
| improved preservation of facial nerve function with use of electrical monitoring during removal of acoustic neuromas. | continuous spontaneous electromyographic activity and responses to electrical stimulation of the facial nerve in the surgical field were monitored in 48 patients undergoing primary removal of an acoustic neuroma. the operative and postoperative results in these patients were compared with the results in 48 patients who were matched for age and size of tumor and who underwent the same surgical procedure without intraoperative monitoring. eighty-three percent of the patients had preoperative evide ... | 2013 | 3807440 |
| naming the cyclic antidepressants. | | 2013 | 3624521 |
| benefits of safety belt use well proven. | | 2012 | 3405607 |
| diagnosis and treatment of neonatal sepsis. | | 2013 | 3570448 |
| [b-cell chronic lymphocytic leukemia complicated by autoimmune thrombocytopenic purpura]. | a 74-year-old japanese male was admitted because of anemia. hepatosplenomegaly, lymphoadenopathy, and purpura were not found. the laboratory data on admission revealed that the white-cell count was 9,400/microliters, the hemoglobin 11.1 g/dl, and the platelet count 17,000/microliters. platelet-associated igg was 794.2 ng/10(7) cells. the patient was diagnosed as having autoimmune thrombocytopenic purpura (atp) at this time. he was treated with prednisolone, but his thrombocytopenia not improve. ... | 2006 | 1635169 |
| [evaluation of collagenous protein levels in inflamed middle ear mucosa]. | the collagenous protein level in the inflammatory status of middle ear mucosa taken during the surgery in 16 patients were analysed. the more accentuated changes were in longer duration of disease. the collagenous protein level play probably an important role in the healing processes after tympanoplasty. | 2007 | 1896187 |
| [fibrous lesions of the skeleton in infants and children]. | | 2011 | 3122625 |
| [importance of studying the sputum of pneumonia and bronchitis patients]. | | 2014 | 4002152 |
| the incidence of poliovirus in chimpanzees (pan troglodytes). | | 2015 | 4315780 |