Ruminococcus Albus
Mostrando 13-24 de 73 artigos, teses e dissertações.
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13. Cellulase from Ruminococcus albus and Mixed Rumen Microorganisms1
Cellulase in the cultural filtrates of Ruminococcus albus and cellulase extracted from mixed rumen microorganisms were investigated with acid-swollen cellulose and carboxymethylcellulose as substrates. Maximal activity occurred at approximately pH 5.8 and 47 C. Apparent Michaelis constants (Km) varied between 0.53 and 0.02% carboxymethylcellulose, depending
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14. Incorporation of [15N]Ammonia by the Cellulolytic Ruminal Bacteria Fibrobacter succinogenes BL2, Ruminococcus albus SY3, and Ruminococcus flavefaciens 17
The origin of cell nitrogen and amino acid nitrogen during growth of ruminal cellulolytic bacteria in different growth media was investigated by using 15NH3. At high concentrations of peptides (Trypticase, 10 g/liter) and amino acids (15.5 g/liter), significant amounts of cell nitrogen of Fibrobacter succinogenes BL2 (51%), Ruminococcus flavefaciens 17 (43%)
American Society for Microbiology.
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15. Competition for cellobiose among three predominant ruminal cellulolytic bacteria under substrate-excess and substrate-limited conditions.
The ruminal cellulolytic bacteria Ruminococcus flavefaciens FD-1 and Fibrobacter succinogenes S85 coexisted in substrate-excess coculture with about equal population size, but R. flavefaciens outcompeted F. succinogenes for cellobiose in the substrate-limited cocultures whether the two strains were coinoculated or a steady-state culture of F. succinogenes wa
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16. 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 ferred
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17. Formation of Hydrogen and Formate by Ruminococcus albus
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18. 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 NH4+. B. amylophilus grew well in the basal medium supplemented with starch and produced branched-chain amino acids afte
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19. Identification of Ruminococcus flavefaciens as the Predominant Cellulolytic Bacterial Species of the Equine Cecum
Detection and quantification of cellulolytic bacteria with oligonucleotide probes showed that Ruminococcus flavefaciens was the predominant species in the pony and donkey cecum. Fibrobacter succinogenes and Ruminococcus albus were present at low levels. Four isolates, morphologically resembling R. flavefaciens, differed from ruminal strains by their carbohyd
American Society for Microbiology.
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20. DNA sequence of a beta-glucosidase from Ruminococcus albus.
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21. 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
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22. 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
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23. Glucose Fermentation Products of Ruminococcus albus Grown in Continuous Culture with Vibrio succinogenes: Changes Caused by Interspecies Transfer of H2
The influence of a H2-utilizing organism, Vibrio succinogenes, on the fermentation of limiting amounts of glucose by a carbohydrate-fermenting, H2-producing organism, Ruminococcus albus, was studied in continuous cultures. Growth of V. succinogenes depended on the production of H2 from glucose by R. albus. V. succinogenes used the H2 produced by R. albus to
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24. 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 fra