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Journal of Dairy Science Jul 1999The effects of virginiamycin, an agent active against Gram-positive lactic acid-producing bacteria, and NaHCO3 on ruminal and fecal pH, rumen volatile fatty acid...
The effects of virginiamycin, an agent active against Gram-positive lactic acid-producing bacteria, and NaHCO3 on ruminal and fecal pH, rumen volatile fatty acid proportions, blood metabolites, and milk production and composition were assessed. This study was conducted over 28 d and involved 71 dairy cows that grazed predominantly ryegrass, oats, and clover, and that were fed 10 kg of concentrate pellets/d per head. The pellets contained (per kilogram) no dietary additive, 30 mg of virginiamycin, 20 g of NaHCO3, or 30 mg of virginiamycin and 20 g of NaHCO3 on a DM basis. Ruminal pH tended to be higher in cows fed pellets containing virginiamycin (7.0 vs. 6.9; SED = 0.16). The results of in vitro incubation of ruminal fluid with glucose found the potential for L-lactic acid accumulation in ruminal fluid to be significantly lower in cows fed virginiamycin (15.5 vs. 35.3 mmol/L; SED = 2.98). Cows fed virginiamycin had significantly higher fecal pH (6.72 vs. 6.57; SED = 0.08) and produced more milk (23.94 vs. 23.32 kg/d) and more lactose than those not fed virginiamycin. No effects of NaHCO3 on fecal pH, in vitro potential for L-lactic acid accumulation in ruminal fluid, or milk production were observed, but ruminal pH tended to be higher and ruminal acetate proportion was greater for cows fed NaHCO3. Milk fat and milk protein percentage did not differ significantly as a result of dietary treatment. These data suggest that the inclusion of virginiamycin in the diet will reduce L-lactic acid accumulation in ruminal fluid and increase fecal pH in grazing dairy cattle fed concentrate supplements.
Topics: Animal Feed; Animals; Anti-Bacterial Agents; Avena; Cattle; Dietary Supplements; Female; Gastrointestinal Contents; Hydrogen-Ion Concentration; Lactation; Milk; Poaceae; Rumen; Sodium Bicarbonate; Virginiamycin
PubMed: 10416170
DOI: 10.3168/jds.S0022-0302(99)75382-8 -
Expert Review of Anti-infective Therapy May 2021Streptogramins (pristinamycin and quinupristin-dalfopristin) can be interesting options for the treatment of infections due to Gram-positive cocci, especially... (Review)
Review
INTRODUCTION
Streptogramins (pristinamycin and quinupristin-dalfopristin) can be interesting options for the treatment of infections due to Gram-positive cocci, especially multidrug-resistant isolates.
AREAS COVERED
This review provides an updated overview of structural and activity characteristics, mechanisms of action and resistance, pharmacokinetic/pharmacodynamic, and clinical use of streptogramins.
EXPERT OPINION
The streptogramin antibiotics act by inhibition of the bacterial protein synthesis. They are composed of two chemically distinct compounds, namely type A and type B streptogramins, which exert a rapid bactericidal activity against a wide range of Gram-positive bacteria (including methicillin-resistant staphylococci and vancomycin-resistant enterococci). Several mechanisms of resistance have been identified in staphylococci and enterococci but the prevalence of streptogramin resistance among clinical isolates remains very low. Even if only a few randomized clinical trials have been conducted, the efficacy of pristinamycin has been largely demonstrated with an extensive use for 50 years in France and some African countries. Despite its effectiveness in the treatment of severe Gram-positive bacterial infections demonstrated in several studies and the low rate of reported resistance, the clinical use of quinupristin-dalfopristin has remained limited, mainly due to its poor tolerance. Altogether, streptogramins (especially pristinamycin) can be considered as potential alternatives for the treatment of Gram-positive infections.
Topics: Animals; Anti-Bacterial Agents; Drug Resistance, Bacterial; Gram-Positive Bacteria; Gram-Positive Bacterial Infections; Humans; Pristinamycin; Randomized Controlled Trials as Topic; Streptogramins; Virginiamycin
PubMed: 33030387
DOI: 10.1080/14787210.2021.1834851 -
The Journal of Antibiotics Feb 1977Reduction of virginiamycin S with sodium borohydride produces allo- and normal-dihydro-virginiamycin S. Reduction of the tosylhydrazone of virginiamycin S with sodium...
Reduction of virginiamycin S with sodium borohydride produces allo- and normal-dihydro-virginiamycin S. Reduction of the tosylhydrazone of virginiamycin S with sodium cyanoborohydride affords deoxyvirginiamycin S. These compounds are less active than virginiamycin S. Like virginiamycin S they enhance the activity of virginiamycin M1.
Topics: Bacteria; Chemical Phenomena; Chemistry; Drug Resistance, Microbial; Drug Synergism; Hydrolysis; Oxidation-Reduction; Structure-Activity Relationship; Virginiamycin
PubMed: 403168
DOI: 10.7164/antibiotics.30.141 -
The Journal of Organic Chemistry Dec 2011A stereoselective synthesis of the antibiotic (-)-virginiamycin M(2) is detailed. A convergent strategy was utilized that proceeded in 10 steps (longest linear sequence)...
A stereoselective synthesis of the antibiotic (-)-virginiamycin M(2) is detailed. A convergent strategy was utilized that proceeded in 10 steps (longest linear sequence) from enantioenriched silane (S)-15. This reagent, which was prepared via a Rh(II)- or Cu(I)-catalyzed carbenoid Si-H insertion, was used to introduce the desired olefin geometry and stereocenters of the C1-C5 propionate subunit. A modified Negishi cross-coupling or an efficient alkoxide-directed titanium-mediated alkyne-alkyne reductive coupling strategy was utilized to assemble the trisubstituted (E,E)-diene. An underutilized late-stage SmI(2)-mediated macrocyclization was employed to construct the 23-membered macrocycle scaffold of the natural product.
Topics: Alkenes; Alkynes; Anti-Bacterial Agents; Catalysis; Chromatography, High Pressure Liquid; Copper; Cyclization; Humans; Hydrogen; Magnetic Resonance Spectroscopy; Molecular Structure; Oxidation-Reduction; Rhodium; Silanes; Silicon; Stereoisomerism; Virginiamycin
PubMed: 22070230
DOI: 10.1021/jo202119p -
European Journal of Biochemistry May 1978Virginiamycin S is an inhibitor of protein synthesis in vivo. In this paper we show by equilibrium dialysis that it binds specifically to the 50-S subunit of Escherichia...
Virginiamycin S is an inhibitor of protein synthesis in vivo. In this paper we show by equilibrium dialysis that it binds specifically to the 50-S subunit of Escherichia coli ribosomes, with one binding site per subunit. This binding is not altered by the presence of chloramphenicol, tetracycline or puromycin but is competed for by erythromycin. Using the splitting-reconstitution method, it could be demonstrated that protein L16 is absolutely required for the binding of virginiamycin S to the 50-S subunit.
Topics: Binding Sites; Binding, Competitive; Erythromycin; Escherichia coli; Kinetics; Ribosomal Proteins; Ribosomes; Virginiamycin
PubMed: 95947
DOI: 10.1111/j.1432-1033.1978.tb12298.x -
Molecular & General Genetics : MGG 1980Resistance to virginiamycin S (VS, a type B synergimycin) has been mapped in Bacillus subtilis. Transduction experiments with phage PBS1 indicate that the gene for...
Resistance to virginiamycin S (VS, a type B synergimycin) has been mapped in Bacillus subtilis. Transduction experiments with phage PBS1 indicate that the gene for virginiamycin S resistance (VSR) is cotransduced with the markers pur A16 (20%) and cys A14 (46-49%). Transformation experiments indicate that the gene for virginiamycin S resistance maps between the markers for elongation factor G and erythromycin resistance, and is therefore located within the gene cluster of ribosomal proteins.
Topics: Bacillus subtilis; Chromosome Mapping; Coliphages; Drug Resistance, Microbial; Genes; Transduction, Genetic; Transformation, Bacterial; Virginiamycin
PubMed: 6780761
DOI: 10.1007/BF00268073 -
Emergency Medicine Clinics of North... Nov 2000It is easy to become overwhelmed by the amount of information available on the new antibiotics and difficult to keep abreast of the appropriate indications for each of... (Review)
Review
It is easy to become overwhelmed by the amount of information available on the new antibiotics and difficult to keep abreast of the appropriate indications for each of them. For most patients with community-acquired infections, the first-line agent is usually not one of the newer agents, but a standard regimen, or at times, no antibiotic at all. The development of resistance is likely to parallel the extent to which these agents are prescribed. They should be used only when standard treatment fails, when compliance with treatment is a real and serious issue, or when the patient has a real allergic reaction to the standard regimen.
Topics: Anti-Bacterial Agents; Anti-Infective Agents; Bacterial Infections; Cephalosporins; Fluoroquinolones; Fosfomycin; Humans; Macrolides; Virginiamycin
PubMed: 11130933
DOI: 10.1016/s0733-8627(05)70153-x -
Poultry Science Oct 1986An experiment was conducted with broiler chicks to determine the influence of Virginiamycin on chicks fed diets with four levels of energy. Addition of the Virginiamycin...
An experiment was conducted with broiler chicks to determine the influence of Virginiamycin on chicks fed diets with four levels of energy. Addition of the Virginiamycin to the diet resulted in significantly improved body weight and feed efficiency at all levels of energy. The greatest improvement was obtained at the lowest level of energy. Addition of Virginiamycin to the diet decreased the energy required to produce a unit of body weight.
Topics: Animals; Body Weight; Chickens; Diet; Energy Metabolism; Virginiamycin
PubMed: 3099277
DOI: 10.3382/ps.0651984 -
Journal of Natural Products 1986Conversion of L-phenylalanine to L-phenylglycine in the biosynthesis of virginiamycin S1 (1) can, in principle, take place with intramolecular nitrogen transfer or with...
Conversion of L-phenylalanine to L-phenylglycine in the biosynthesis of virginiamycin S1 (1) can, in principle, take place with intramolecular nitrogen transfer or with intermolecular nitrogen transfer. A labeling experiment with DL-[3-13C, 15N]phenylalanine showed that the resulting L-phenylglycine contained no labeled nitrogen, indicating that the rearrangement proceeds via an intermolecular pathway.
Topics: Chemical Phenomena; Chemistry; Glycine; Mass Spectrometry; Phenylalanine; Streptomyces; Virginiamycin
PubMed: 3097264
DOI: 10.1021/np50046a011 -
The Medical Letter on Drugs and... Nov 1999
Topics: Clinical Trials as Topic; Costs and Cost Analysis; Dose-Response Relationship, Drug; Drug Interactions; Drug Therapy, Combination; Enterococcus faecium; Fees, Pharmaceutical; Gram-Positive Bacterial Infections; Humans; Infusions, Intravenous; Vancomycin Resistance; Virginiamycin
PubMed: 10987009
DOI: No ID Found