Base de dados : MEDLINE
Pesquisa : D09.698.718.220 [Categoria DeCS]
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  1 / 108 MEDLINE  
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[PMID]:27898865
[Au] Autor:Lemos BJ; Castro FG; Santos LS; Mendonça BP; Couto VR; Fernandes JJ
[Ti] Título:Monensin, virginiamycin, and flavomycin in a no-roughage finishing diet fed to zebu cattle.
[So] Source:J Anim Sci;94(10):4307-4314, 2016 Oct.
[Is] ISSN:1525-3163
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Two experiments were designed to evaluate the effects of monensin, virginiamycin, and flavomycin on growth performance, carcass characteristics, apparent total tract nutrient digestibility, and rumen fermentation of zebu cattle fed a no-roughage finishing diet (whole shelled corn [WSC] based). In Exp. 1, 100 crossbred bulls (; 392 kg [SD 46.8] average initial BW) were blocked by initial BW in a 101-d feedlot trial. Five treatments were evaluated using 4 pens per treatment (5 bulls/pen): monensin at 30 mg/kg DM, virginiamycin at 25 mg/kg DM, monensin at 20 mg/kg DM plus virginiamycin at 25 mg/kg DM, flavomycin at 4.4 mg/kg DM, and monensin at 20 mg/kg DM plus flavomycin at 2.2 mg/kg DM. There were no differences in growth performance (final BW, ADG, DMI, and G:F; ≥ 0.527) and carcass characteristics (HCW, dressing percent, and 12th-rib fat; ≥ 0.235) among treatments. In Exp. 2, 7 ruminally fistulated steers were used in a 7 × 7 Latin square design to evaluate the 5 treatments of Exp. 1 and 2 additional treatments: monensin at 30 mg/kg DM plus virginiamycin at 25 mg/kg DM and monensin at 20 mg/kg DM plus flavomycin at 4.4 mg/kg DM. Experimental periods were 14 d in length (9 d of adaptation and 5 d of measurements). Apparent total tract DM, OM, CP, and NDF digestibilities were similar among treatments ( ≥ 0.224). There was no treatment effect ( ≥ 0.253) in rumen fermentation responses (ruminal pH, rumen ammonia nitrogen, VFA, and number of protozoa). In conclusion, no evidence of benefits to cattle fed a no-roughage WSC-based diet was found to support the use of monensin combined with virginiamycin or flavomycin in the doses tested herein.
[Mh] Termos MeSH primário: Bambermicinas/farmacologia
Bovinos
Dieta/veterinária
Fibras na Dieta
Monensin/farmacologia
Virginiamicina/farmacologia
[Mh] Termos MeSH secundário: Ração Animal/análise
Fenômenos Fisiológicos da Nutrição Animal
Animais
Antibacterianos/farmacologia
Composição Corporal/efeitos dos fármacos
Digestão/fisiologia
Fermentação
Trato Gastrointestinal/efeitos dos fármacos
Masculino
Inibidores da Síntese de Proteínas/farmacologia
Ionóforos de Próton/farmacologia
Rúmen/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Anti-Bacterial Agents); 0 (Dietary Fiber); 0 (Protein Synthesis Inhibitors); 0 (Proton Ionophores); 11006-76-1 (Virginiamycin); 11015-37-5 (Bambermycins); 906O0YJ6ZP (Monensin)
[Em] Mês de entrada:1704
[Cu] Atualização por classe:171116
[Lr] Data última revisão:
171116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161130
[St] Status:MEDLINE
[do] DOI:10.2527/jas.2016-0504


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[PMID]:27344593
[Au] Autor:Horbal L; Ostash B; Luzhetskyy A; Walker S; Kalinowski J; Fedorenko V
[Ad] Endereço:Saarland University, Campus C2.3, 66123, Saarbrücken, Germany. lihorbal@gmail.com.
[Ti] Título:A gene cluster for the biosynthesis of moenomycin family antibiotics in the genome of teicoplanin producer Actinoplanes teichomyceticus.
[So] Source:Appl Microbiol Biotechnol;100(17):7629-38, 2016 Sep.
[Is] ISSN:1432-0614
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo:Moenomycins are phosphoglycolipid antibiotics notable for their extreme potency, unique mode of action, and proven record of use in animal nutrition without selection for resistant microflora. There is a keen interest in manipulation of structures of moenomycins in order to better understand their structure-activity relationships and to generate improved analogs. Only two almost identical moenomycin biosynthetic gene clusters are known, limiting our knowledge of the evolution of moenomycin pathways and our ability to genetically diversify them. Here, we report a novel gene cluster (tchm) that directs production of the phosphoglycolipid teichomycin in Actinoplanes teichomyceticus. Its overall genetic architecture is significantly different from that of the moenomycin biosynthesis (moe) gene clusters of Streptomyces ghanaensis and Streptomyces clavuligerus, featuring multiple gene rearrangements and two novel structural genes. Involvement of the tchm cluster in teichomycin biosynthesis was confirmed via heterologous co-expression of amidotransferase tchmH5 and moe genes. Our work sets the background for further engineering of moenomycins and for deeper inquiries into the evolution of this fascinating biosynthetic pathway.
[Mh] Termos MeSH primário: Actinobacteria/genética
Antibacterianos/biossíntese
Bambermicinas/biossíntese
Família Multigênica/genética
Oligossacarídeos/biossíntese
Teicoplanina/biossíntese
[Mh] Termos MeSH secundário: Actinobacteria/metabolismo
Vias Biossintéticas/genética
Regulação Bacteriana da Expressão Gênica
Genes Bacterianos
Bactérias Gram-Positivas/efeitos dos fármacos
Oligossacarídeos/genética
Relação Estrutura-Atividade
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Anti-Bacterial Agents); 0 (Oligosaccharides); 0 (moenomycin); 11015-37-5 (Bambermycins); 61036-62-2 (Teicoplanin)
[Em] Mês de entrada:1702
[Cu] Atualização por classe:170227
[Lr] Data última revisão:
170227
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160627
[St] Status:MEDLINE
[do] DOI:10.1007/s00253-016-7685-3


  3 / 108 MEDLINE  
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[PMID]:25462814
[Au] Autor:Bury D; Dahmane I; Derouaux A; Dumbre S; Herdewijn P; Matagne A; Breukink E; Mueller-Seitz E; Petz M; Terrak M
[Ad] Endereço:Department of Food Chemistry, Faculty of Mathematics and Natural Sciences, University of Wuppertal, Gaussstr. 20, 42119 Wuppertal, Germany. Electronic address: bury@ipa-dguv.de.
[Ti] Título:Positive cooperativity between acceptor and donor sites of the peptidoglycan glycosyltransferase.
[So] Source:Biochem Pharmacol;93(2):141-50, 2015 Jan 15.
[Is] ISSN:1873-2968
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The glycosyltransferases of family 51 (GT51) catalyze the polymerization of lipid II to form linear glycan chains, which, after cross linking by the transpeptidases, form the net-like peptidoglycan macromolecule. The essential function of the GT makes it an attractive antimicrobial target; therefore a better understanding of its function and its mechanism of interaction with substrates could help in the design and the development of new antibiotics. In this work, we have used a surface plasmon resonance Biacore(®) biosensor, based on an amine derivative of moenomycin A immobilized on a sensor chip surface, to investigate the mechanism of binding of substrate analogous inhibitors to the GT. Addition of increasing concentrations of moenomycin A to the Staphylococcus aureus MtgA led to reduced binding of the protein to the sensor chip as expected. Remarkably, in the presence of low concentrations of the most active disaccharide inhibitors, binding of MtgA to immobilized moenomycin A was found to increase; in contrast competition with moenomycin A occurred only at high concentrations. This finding suggests that at low concentrations, the lipid II analogs bind to the acceptor site and induce a cooperative binding of moenomycin A to the donor site. Our results constitute the first indication of the existence of a positive cooperativity between the acceptor and the donor sites of peptidoglycan GTs. In addition, our study indicates that a modification of two residues (L119N and F120S) within the hydrophobic region of MtgA can yield monodisperse forms of the protein with apparently no change in its secondary structure content, but this is at the expense of the enzyme function.
[Mh] Termos MeSH primário: Interações Microbianas/fisiologia
Peptidoglicano Glicosiltransferase/química
Peptidoglicano Glicosiltransferase/metabolismo
Staphylococcus aureus/metabolismo
[Mh] Termos MeSH secundário: Bambermicinas/metabolismo
Ligação Proteica/fisiologia
Estrutura Secundária de Proteína
Estrutura Terciária de Proteína
Ressonância de Plasmônio de Superfície/métodos
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
11015-37-5 (Bambermycins); 2RO799DN06 (moenomycin A); EC 2.4.1.129 (Peptidoglycan Glycosyltransferase)
[Em] Mês de entrada:1503
[Cu] Atualização por classe:150110
[Lr] Data última revisão:
150110
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:141203
[St] Status:MEDLINE


  4 / 108 MEDLINE  
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[PMID]:24890564
[Au] Autor:Wang Y; Chan FY; Sun N; Lui HK; So PK; Yan SC; Chan KF; Chiou J; Chen S; Abagyan R; Leung YC; Wong KY
[Ad] Endereço:Department of Applied Biology and Chemical Technology and State Key Laboratory of Chirosciences, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China.
[Ti] Título:Structure-based design, synthesis, and biological evaluation of isatin derivatives as potential glycosyltransferase inhibitors.
[So] Source:Chem Biol Drug Des;84(6):685-96, 2014 Dec.
[Is] ISSN:1747-0285
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Peptidoglycan glycosyltransferase (PGT) has been shown to be an important pharmacological target for the inhibition of bacterial cell wall biosynthesis. Structure-based virtual screening of about 3,000,000 commercially available compounds against the crystal structure of the glycosyltransferase (GT) domain of the Staphylococcus aureus penicillin-binding protein 2 (S. aureus PBP2) resulted in identification of an isatin derivative, 2-(3-(2-carbamimidoylhydrazono)-2-oxoindolin-1-yl)-N-(m-tolyl)acetamide (4) as a novel potential GT inhibitor. A series of 4 derivatives were synthesized. Several compounds showed more active antimicrobial activity than the initial hit compound 4, in particular 2-(3-(2-carbamimidoylhydrazono)-2-oxoindolin-1-yl)-N-(3-nitrophenyl)acetamide (4l), against Gram-positive Bacillus subtilis and S. aureus with MIC values of 24 and 48 µg/mL, respectively. Saturation transfer difference (STD) NMR study revealed that there is a binding contact between 4l and the GT domain of S. aureus PBP2. Competitive STD-NMR further proved that 4l and moenomycin A bind to GT domain in a competitive manner. Molecular docking study suggests a potential binding pocket of 4l in the GT domain of S. aureus PBP2. Taken together, compound 4l would provide a new scaffold for further development of potent GT inhibitors.
[Mh] Termos MeSH primário: Antibacterianos/síntese química
Desenho de Drogas
Inibidores Enzimáticos/síntese química
Isatina/química
Peptidoglicano Glicosiltransferase/antagonistas & inibidores
[Mh] Termos MeSH secundário: Antibacterianos/química
Antibacterianos/farmacologia
Bacillus subtilis/efeitos dos fármacos
Bambermicinas/química
Bambermicinas/farmacologia
Sítios de Ligação
Inibidores Enzimáticos/química
Inibidores Enzimáticos/farmacologia
Isatina/síntese química
Isatina/farmacologia
Testes de Sensibilidade Microbiana
Simulação de Acoplamento Molecular
Peptidoglicano Glicosiltransferase/metabolismo
Estrutura Terciária de Proteína
Staphylococcus aureus/efeitos dos fármacos
Staphylococcus aureus/enzimologia
Relação Estrutura-Atividade
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Anti-Bacterial Agents); 0 (Enzyme Inhibitors); 11015-37-5 (Bambermycins); 2RO799DN06 (moenomycin A); 82X95S7M06 (Isatin); EC 2.4.1.129 (Peptidoglycan Glycosyltransferase)
[Em] Mês de entrada:1507
[Cu] Atualização por classe:141114
[Lr] Data última revisão:
141114
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:140604
[St] Status:MEDLINE
[do] DOI:10.1111/cbdd.12361


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[PMID]:24775303
[Au] Autor:Tseng YY; Liou JM; Hsu TL; Cheng WC; Wu MS; Wong CH
[Ad] Endereço:Graduate Institute of Life Sciences, National Defense Medical Center, Taipei 114, Taiwan; Genomics Research Center, Academia Sinica, Taipei 115, Taiwan.
[Ti] Título:Development of bacterial transglycosylase inhibitors as new antibiotics: moenomycin A treatment for drug-resistant Helicobacter pylori.
[So] Source:Bioorg Med Chem Lett;24(11):2412-4, 2014 Jun 01.
[Is] ISSN:1464-3405
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The problem of multidrug-resistant Helicobacter pylori requires new antibiotics development. We have evaluated a potential antibiotics, moenomycin A, which is classified as a phosphoglycolipid antibiotics that targets transglycosylase and is previously thought to be limited in Gram-positive bacteria. Herein, we report the activity of moenomycin A against multidrug-resistant H. pylori and the isolates from patients with different gastrointestinal diseases.
[Mh] Termos MeSH primário: Antibacterianos/farmacologia
Bambermicinas/farmacologia
Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos
Inibidores Enzimáticos/farmacologia
Glicosiltransferases/antagonistas & inibidores
Helicobacter pylori/efeitos dos fármacos
Neoplasias Gástricas/microbiologia
[Mh] Termos MeSH secundário: Antibacterianos/síntese química
Antibacterianos/química
Bambermicinas/síntese química
Bambermicinas/química
Desenho de Drogas
Úlcera Duodenal/microbiologia
Inibidores Enzimáticos/síntese química
Inibidores Enzimáticos/química
Gastrite/microbiologia
Glicosiltransferases/metabolismo
Infecções por Helicobacter/tratamento farmacológico
Infecções por Helicobacter/microbiologia
Helicobacter pylori/enzimologia
Helicobacter pylori/isolamento & purificação
Seres Humanos
Testes de Sensibilidade Microbiana
Conformação Molecular
Úlcera Gástrica/microbiologia
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Anti-Bacterial Agents); 0 (Enzyme Inhibitors); 11015-37-5 (Bambermycins); 2RO799DN06 (moenomycin A); EC 2.4.- (Glycosyltransferases)
[Em] Mês de entrada:1501
[Cu] Atualização por classe:140509
[Lr] Data última revisão:
140509
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:140430
[St] Status:MEDLINE


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[PMID]:24509312
[Au] Autor:Villet RA; Truong-Bolduc QC; Wang Y; Estabrooks Z; Medeiros H; Hooper DC
[Ad] Endereço:Division of Infectious Diseases and Medical Services, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA.
[Ti] Título:Regulation of expression of abcA and its response to environmental conditions.
[So] Source:J Bacteriol;196(8):1532-9, 2014 Apr.
[Is] ISSN:1098-5530
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The ATP-dependent transporter gene abcA in Staphylococcus aureus confers resistance to hydrophobic ß-lactams. In strain ISP794, abcA is regulated by the transcriptional regulators MgrA and NorG and shares a 420-nucleotide intercistronic region with the divergently transcribed pbp4 gene, which encodes the transpeptidase Pbp4. Exposure of exponentially growing cells to iron-limited media, oxidative stress, and acidic pH (5.5) for 0.5 to 2 h had no effect on abcA expression. In contrast, nutrient limitation produced a significant increase in abcA transcripts. We identified three additional regulators (SarA, SarZ, and Rot) that bind to the overlapping promoter region of abcA and pbp4 in strain MW2 and investigated their role in the regulation of abcA expression. Expression of abcA is decreased by 10.0-fold in vivo in a subcutaneous abscess model. In vitro, abcA expression depends on rot and sarZ regulators. Moenomycin A exposure of strain MW2 produced an increase in abcA transcripts. Relative to MW2, the MIC of moenomycin was decreased 8-fold for MW2ΔabcA and increased 10-fold for the MW2 abcA overexpresser, suggesting that moenomycin is a substrate of AbcA.
[Mh] Termos MeSH primário: Transportadores de Cassetes de Ligação de ATP/metabolismo
Regulação Bacteriana da Expressão Gênica
Staphylococcus aureus/fisiologia
Estresse Fisiológico
[Mh] Termos MeSH secundário: Abscesso/microbiologia
Animais
Antibacterianos/metabolismo
Proteínas de Bactérias/metabolismo
Bambermicinas/metabolismo
Sequência de Bases
Modelos Animais de Doenças
Ensaio de Desvio de Mobilidade Eletroforética
Perfilação da Expressão Gênica
Concentração de Íons de Hidrogênio
Ferro/metabolismo
Camundongos
Dados de Sequência Molecular
Estresse Oxidativo
Regiões Promotoras Genéticas
Ligação Proteica
Proteínas Repressoras/metabolismo
Infecções Cutâneas Estafilocócicas/microbiologia
Staphylococcus aureus/genética
Staphylococcus aureus/metabolismo
Transativadores/metabolismo
Fatores de Transcrição/metabolismo
Transcrição Genética
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, N.I.H., EXTRAMURAL
[Nm] Nome de substância:
0 (Anti-Bacterial Agents); 0 (Bacterial Proteins); 0 (Repressor Proteins); 0 (SarA protein, bacterial); 0 (SarZ protein, Staphylococcus aureus); 0 (Trans-Activators); 0 (Transcription Factors); 0 (rot protein, Staphylococcus aureus); 11015-37-5 (Bambermycins); 2RO799DN06 (moenomycin A); E1UOL152H7 (Iron)
[Em] Mês de entrada:1405
[Cu] Atualização por classe:161019
[Lr] Data última revisão:
161019
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:140211
[St] Status:MEDLINE
[do] DOI:10.1128/JB.01406-13


  7 / 108 MEDLINE  
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[PMID]:24164498
[Au] Autor:Ostash B; Campbell J; Luzhetskyy A; Walker S
[Ad] Endereço:Department of Genetics and Biotechnology, Ivan Franko National University of Lviv, 4 Hrushevskoho st., Lviv, 79005, Ukraine; Department of Microbiology and Immunobiology, Harvard Medical School, 4 Blackfan Circle, Boston, MA, 02115, USA.
[Ti] Título:MoeH5: a natural glycorandomizer from the moenomycin biosynthetic pathway.
[So] Source:Mol Microbiol;90(6):1324-38, 2013 Dec.
[Is] ISSN:1365-2958
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The biosynthesis of the phosphoglycolipid antibiotic moenomycin A attracts the attention of researchers hoping to develop new moenomycin-based antibiotics against multidrug resistant Gram-positive infections. There is detailed understanding of most steps of this biosynthetic pathway in Streptomyces ghanaensis (ATCC14672), except for the ultimate stage, where a single pentasaccharide intermediate is converted into a set of unusually modified final products. Here we report that only one gene, moeH5, encoding a homologue of the glutamine amidotransferase (GAT) enzyme superfamily, is responsible for the observed diversity of terminally decorated moenomycins. Genetic and biochemical evidence support the idea that MoeH5 is a novel member of the GAT superfamily, whose homologues are involved in the synthesis of various secondary metabolites as well as K and O antigens of bacterial lipopolysaccharide. Our results provide insights into the mechanism of MoeH5 and its counterparts, and give us a new tool for the diversification of phosphoglycolipid antibiotics.
[Mh] Termos MeSH primário: Antibacterianos/biossíntese
Bambermicinas/biossíntese
Vias Biossintéticas
Streptomyces/enzimologia
[Mh] Termos MeSH secundário: Proteínas de Bactérias/genética
Proteínas de Bactérias/metabolismo
Regulação Bacteriana da Expressão Gênica
Técnicas de Inativação de Genes
Genes Bacterianos
Família Multigênica
Filogenia
Metabolismo Secundário
Homologia de Sequência de Aminoácidos
Streptomyces/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, N.I.H., EXTRAMURAL; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Anti-Bacterial Agents); 0 (Bacterial Proteins); 11015-37-5 (Bambermycins)
[Em] Mês de entrada:1407
[Cu] Atualização por classe:170220
[Lr] Data última revisão:
170220
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:131030
[St] Status:MEDLINE
[do] DOI:10.1111/mmi.12437


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[PMID]:24071920
[Au] Autor:Pedroso AA; Hurley-Bacon AL; Zedek AS; Kwan TW; Jordan AP; Avellaneda G; Hofacre CL; Oakley BB; Collett SR; Maurer JJ; Lee MD
[Ad] Endereço:Poultry Diagnostic and Research Center/Center for Food Safety, The University of Georgia, Athens, GA 30602, USA. mdlee@uga.edu.
[Ti] Título:Can probiotics improve the environmental microbiome and resistome of commercial poultry production?
[So] Source:Int J Environ Res Public Health;10(10):4534-59, 2013 Sep 25.
[Is] ISSN:1660-4601
[Cp] País de publicação:Switzerland
[La] Idioma:eng
[Ab] Resumo:Food animal production systems have become more consolidated and integrated, producing large, concentrated animal populations and significant amounts of fecal waste. Increasing use of manure and litter as a more "natural" and affordable source of fertilizer may be contributing to contamination of fruits and vegetables with foodborne pathogens. In addition, human and animal manure have been identified as a significant source of antibiotic resistance genes thereby serving as a disseminator of resistance to soil and waterways. Therefore, identifying methods to remediate human and animal waste is critical in developing strategies to improve food safety and minimize the dissemination of antibiotic resistant bacteria. In this study, we sought to determine whether withdrawing antibiotic growth promoters or using alternatives to antibiotics would reduce the abundance of antibiotic resistance genes or prevalence of pathogens in poultry litter. Terminal restriction fragment length polymorphism (T-RFLP) paired with high throughput sequencing was used to evaluate the bacterial community composition of litter from broiler chickens that were treated with streptogramin growth-promoting antibiotics, probiotics, or prebiotics. The prevalence of resistance genes and pathogens was determined from sequencing results or PCR screens of litter community DNA. Streptogramin antibiotic usage did not elicit statistically significant differences in Shannon diversity indices or correlation coefficients among the flocks. However, T-RFLP revealed that there were inter-farm differences in the litter composition that was independent of antibiotic usage. The litter from all farms, regardless of antibiotic usage, contained streptogramin resistance genes (vatA, vatB, and vatE), macrolide-lincosamide-streptogramin B resistance genes (ermA and ermB), the tetracycline resistance gene tetM and class 1 integrons. There was inter-farm variability in the distribution of vatA and vatE with no statistically significant differences with regards to usage. Bacterial diversity was higher in litter when probiotics or prebiotics were administered to flocks but as the litter aged, diversity decreased. No statistically significant differences were detected in the abundance of class 1 integrons where 3%-5% of the community was estimated to harbor a copy. Abundance of pathogenic Clostridium species increased in aging litter despite the treatment while the abundance of tetracycline-resistant coliforms was unaffected by treatment. However some treatments decreased the prevalence of Salmonella. These findings suggest that withdrawing antibiotics or administering alternatives to antibiotics can change the litter bacterial community and reduce the prevalence of some pathogenic bacteria, but may not immediately impact the prevalence of antibiotic resistance.
[Mh] Termos MeSH primário: Bactérias/efeitos dos fármacos
Bambermicinas/farmacologia
Galinhas
Probióticos/farmacologia
Virginiamicina/farmacologia
[Mh] Termos MeSH secundário: Animais
Antibacterianos/farmacologia
Bactérias/classificação
Bactérias/genética
Farmacorresistência Bacteriana/efeitos dos fármacos
Microbiologia Ambiental
Pisos e Cobertura de Pisos
Abrigo para Animais
RNA Ribossômico 16S/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE; RANDOMIZED CONTROLLED TRIAL; RESEARCH SUPPORT, U.S. GOV'T, NON-P.H.S.
[Nm] Nome de substância:
0 (Anti-Bacterial Agents); 0 (RNA, Ribosomal, 16S); 11006-76-1 (Virginiamycin); 11015-37-5 (Bambermycins)
[Em] Mês de entrada:1404
[Cu] Atualização por classe:170220
[Lr] Data última revisão:
170220
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:130928
[St] Status:MEDLINE
[do] DOI:10.3390/ijerph10104534


  9 / 108 MEDLINE  
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[PMID]:23448584
[Au] Autor:Gampe CM; Tsukamoto H; Doud EH; Walker S; Kahne D
[Ad] Endereço:Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, USA.
[Ti] Título:Tuning the moenomycin pharmacophore to enable discovery of bacterial cell wall synthesis inhibitors.
[So] Source:J Am Chem Soc;135(10):3776-9, 2013 Mar 13.
[Is] ISSN:1520-5126
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:New antibiotic drugs need to be identified to address rapidly developing resistance of bacterial pathogens to common antibiotics. The natural antibiotic moenomycin A is the prototype for compounds that bind to bacterial peptidoglycan glycosyltransferases (PGTs) and inhibit cell wall biosynthesis, but it cannot be used as a drug. Here we report the chemoenzymatic synthesis of a fluorescently labeled, truncated analogue of moenomycin based on the minimal pharmacophore. This probe, which has optimized enzyme binding properties compared to moenomycin, was designed to identify low-micromolar inhibitors that bind to conserved features in PGT active sites. We demonstrate its use in displacement assays using PGTs from S. aureus, E. faecalis, and E. coli. 110,000 compounds were screened against S. aureus SgtB, and we identified a non-carbohydrate based compound that binds to all PGTs tested. We also show that the compound inhibits in vitro formation of peptidoglycan chains by several different PGTs. Thus, this assay enables the identification of small molecules that target PGT active sites, and may provide lead compounds for development of new antibiotics.
[Mh] Termos MeSH primário: Antibacterianos/farmacologia
Bambermicinas/farmacologia
Parede Celular/efeitos dos fármacos
Peptidoglicano Glicosiltransferase/antagonistas & inibidores
Staphylococcus aureus/efeitos dos fármacos
[Mh] Termos MeSH secundário: Antibacterianos/biossíntese
Antibacterianos/química
Bambermicinas/biossíntese
Bambermicinas/química
Parede Celular/metabolismo
Testes de Sensibilidade Microbiana
Estrutura Molecular
Peptidoglicano Glicosiltransferase/metabolismo
Staphylococcus aureus/citologia
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, N.I.H., EXTRAMURAL; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Anti-Bacterial Agents); 11015-37-5 (Bambermycins); 2RO799DN06 (moenomycin A); EC 2.4.1.129 (Peptidoglycan Glycosyltransferase)
[Em] Mês de entrada:1309
[Cu] Atualização por classe:170220
[Lr] Data última revisão:
170220
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:130302
[St] Status:MEDLINE
[do] DOI:10.1021/ja4000933


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[PMID]:23265883
[Au] Autor:Koyama N; Tokura Y; Takahashi Y; Tomoda H
[Ad] Endereço:Graduate School of Pharmaceutical Sciences, Kitasato University, 5-9-1 Shirokane, Tokyo 108-8641, Japan.
[Ti] Título:Discovery of nosokophic acid, a predicted intermediate of moenomycins, from nosokomycin-producing Streptomyces sp. K04-0144.
[So] Source:Bioorg Med Chem Lett;23(3):860-3, 2013 Feb 01.
[Is] ISSN:1464-3405
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:A new actinomycete metabolite designated nosokophic acid was isolated from the culture broth of nosokomycin-producing Streptomyces sp. K04-0144, and the structure was elucidated by various NMR experiments. Nosokophic acid was found to be 3-phosphoglycosyl-2-sesquiterpenyl dihydroxypropionic acid, a predicted biosynthetic intermediate of nosokomycin-related moenomycins. The compound showed no activity against MRSA, but potentiated imipenem activity against MRSA by 512-fold.
[Mh] Termos MeSH primário: Bambermicinas/metabolismo
Descoberta de Drogas
Ácidos Hexurônicos/química
Organofosfatos/química
Streptomyces/metabolismo
[Mh] Termos MeSH secundário: Antibacterianos/química
Antibacterianos/farmacologia
Bambermicinas/química
Sinergismo Farmacológico
Ácidos Hexurônicos/farmacologia
Imipenem/farmacologia
Espectroscopia de Ressonância Magnética
Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos
Testes de Sensibilidade Microbiana
Estrutura Molecular
Organofosfatos/farmacologia
Streptomyces/química
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (3-phosphoglycosyl-2-sesquiterpenyl dihydroxypropionic acid); 0 (Anti-Bacterial Agents); 0 (Hexuronic Acids); 0 (Organophosphates); 11015-37-5 (Bambermycins); 71OTZ9ZE0A (Imipenem)
[Em] Mês de entrada:1306
[Cu] Atualização por classe:131121
[Lr] Data última revisão:
131121
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:121226
[St] Status:MEDLINE



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