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Showing 1 to 11 of 11 for “"Virginiamycin"”.
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The biosynthesis of virginiamycin S₁
The biosynthesis of virginiamycin S₁, a macrocyclic peptidolactone antibiotic, was studied by growing a strain of Streptomyces virginiae in a complex medium and observing the incorporation of radiolabeled compounds into the antibiotic. These studies have established several of the biosynthetic …
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Studies in the biosynthesis of virginiamycin S₁
… the biosynthesis of three amino acid residues in virginiamycin S₁ have been studied in Streptomyces virginiae by the incorporation of amino acid precursors labeled with either radioactive or stable isotopes. L-Lysine-U-¹⁴C was incorporated into both the 4-oxo-L-pipecolic acid and …
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Stereochemical aspects of virginiamycin biosynthesis: biosynthesis of antibiotic A33853
… formation of the unusual amino acids found in virginiamycin M₁ and A33853 were investigated. Specifically tritiated and carbon 14 labeled serines were incorporated into virginiamycin M₁. (2S)-serine and (2S,3R)-[3-³H] serine were found to be precursors, thus giving evidence of stereochemical …
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A comparison of virginiamycin and a lactobacillus probiotic as feed additives for swine and the effects of virginiamycin supplementation and crowding stress on swine performance
… available lactobacillus probiotic and virginiamycin, a gram-positive antibiotic (experiment I) and to evaluate the feedlot performance of starter and grower-finisher swine housed under conditions of restricted and adequate space allowance fed diets with and without virginiamycin …
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Synthesis of Labeled 3-Hydroxyproline and Biosynthesis of the Dehydroproline Moiety of Virginiamycin M₁
… is a precursor for the dehydroproline moietyof virginiamycin M1, (R,S)-[carboxyl-¹⁴C]-cis-3-hydroxyproline and S-[3,4-³H] proline with a ³H/¹⁴C of 9 were fed simultaneously to a virginiamycin producing strain of Streptomyces. The resulting antibiotic had a ³H/¹⁴C ratio of 41.3. The proline …
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Impact of virginiamycin on the development of intestinal structure and functional capacity in growing pigs
… Our study tested the hypothesis that diets with virginiamycin would increase intestinal surface area and nutrient processing capacity compared with diets without virginiamycin. Littermate barrows with similar body weight (n=72; 23.0±1.3 kg; 9 weeks of age) were randomized to pens and pens were …
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Methodology to evaluate the nutritive value of feedstuffs for poultry and swine
… to determine the effects of crude fiber and Virginiamycin on digesta rate of passate (RP) and nutritional parameters. Two levels (3.2 and 7.3%) of crude fiber and two levels (0 and 11 ppm) of Virginiamycin were used in a 2 x 2 factorial arrangement of treatments. All diets were isonitrogenous …
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Controlling bacterial contaminants in sugarcane ethanol fermentations
… contamination. Monensin, penicillin and virginiamycin have been shown to reduce bacterial counts in bioethanol but increased incidence of antibiotic resistant bacteria means alternative approaches are needed. To test efficacy of the antimicrobials hen egg white lysozyme, nisin and the …
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Dietary effects on pig health
… populations in the digestive tract of pigs. Virginiamycin treatments reduced the number of total bacterial cells (wk 2: 11.1 vs. 11.5, log/g ileal digesta; wk 3: 11.2 vs. 11.5, log/g ileal digesta; wk 4: 11.3 vs. 12.00, log/g feces; P < 0.05) during the virginiamycin feeding (wk 2 to 4) …
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In ovo and feed application of probiotics or synbiotics and response of broiler chicks to post-hatch necrotic enteritis
… (AGP+): sterile water in ovo fed basal diet with virginiamycin (0.5 kg/MT) as an AGP with NE challenge; NC+: same as NC plus NE challenge; SI+: synbiotic in ovo fed the basal diet and NE challenged; SD+: sterile water in ovo fed basal diet supplemented with synbiotic (0.5 kg/MT feed) and NE …
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Molecular investigation of the influence of environmental factors and subinhibitory antibiotic concentrations on the biofilm formation in Staphylococcus epidermidis
… and the streptogramin growth promoter virginiamycin were found to enhance the ica expression 8 to 11-fold, respectively, whereas penicillin, oxacillin, gentamicin, clindamycin, vancomycin, teicoplanin, ofloxacin, and chloramphenicol had no effects. A weak induction was recorded for …