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Stefan Schwarz - One of the best experts on this subject based on the ideXlab platform.
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identification of abc transporter genes conferring combined pleuromutilin lincosamide streptogramin a resistance in bovine methicillin resistant Staphylococcus aureus and coagulase negative staphylococci
Veterinary Microbiology, 2015Co-Authors: Sarah Wendlandt, Andrea T Fesler, Kristina Kadlec, Stefan SchwarzAbstract:The aim of this study was to investigate the genetic basis of combined pleuromutilin-lincosamide-streptogramin A resistance in 26 unrelated methicillin-resistant Staphylococcus aureus (MRSA) and coagulase-negative staphylococci (CoNS) from dairy cows suffering from mastitis. The 26 pleuromutilin-resistant staphylococcal isolates were screened for the presence of the genes vga(A), vga(B), vga(C), vga(E), vga(E) variant, sal(A), vmlR, cfr, lsa(A), lsa(B), lsa(C), and lsa(E) by PCR. None of the 26 isolates carried the genes vga(B), vga(C), vga(E), vga(E) variant, vmlR, cfr, lsa(A), lsa(B), or lsa(C). Two Staphylococcus haemolyticus and single Staphylococcus xylosus, Staphylococcus Lentus, and Staphylococcus hominis were vga(A)-positive. Twelve S. aureus, two Staphylococcus warneri, as well as single S. Lentus and S. xylosus carried the lsa(E) gene. Moreover, single S. aureus, S. haemolyticus, S. xylosus, and Staphylococcus epidermidis were positive for both genes, vga(A) and lsa(E). The sal(A) gene was found in a single Staphylococcus sciuri. All ABC transporter genes were located in the chromosomal DNA, except for a plasmid-borne vga(A) gene in the S. epidermidis isolate. The genetic environment of the lsa(E)-positive isolates was analyzed using previously described PCR assays. Except for the S. warneri and S. xylosus, all lsa(E)-positive isolates harbored a part of the previously described enterococcal multiresistance gene cluster. This is the first report of the novel lsa(E) gene in the aforementioned bovine CoNS species. This is also the first identification of the sal(A) gene in a S. sciuri from a case of bovine mastitis. Moreover, the sal(A) gene was shown to also confer pleuromutilin resistance.
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florfenicol chloramphenicol exporter gene fexa is part of the novel transposon tn558
Antimicrobial Agents and Chemotherapy, 2005Co-Authors: Corinna Kehrenberg, Stefan SchwarzAbstract:The florfenicol-chloramphenicol exporter gene fexA is part of the novel transposon Tn558 from Staphylococcus Lentus. Similarities between Tn558 and Tn554 from Staphylococcus aureus included the arrangement of the transposase genes tnpA to -C and an att554-like target sequence. Circular forms of Tn558 were detected and suggest the functional activity of this transposon.
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fexa a novel Staphylococcus Lentus gene encoding resistance to florfenicol and chloramphenicol
Antimicrobial Agents and Chemotherapy, 2004Co-Authors: Corinna Kehrenberg, Stefan SchwarzAbstract:The Staphylococcus Lentus plasmid pSCFS2 carries a novel florfenicol-chloramphenicol resistance gene, designated fexA, encoding a protein of 475 amino acids with 14 transmembrane domains. The FexA protein differs from all previously known proteins involved in the efflux of chloramphenicol and florfenicol. Induction of fexA expression by chloramphenicol and florfenicol occurs via translational attenuation.
Y Zhang - One of the best experts on this subject based on the ideXlab platform.
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diversity of staphylococcal cassette chromosome in coagulase negative staphylococci from animal sources
Journal of Applied Microbiology, 2009Co-Authors: Y Zhang, S Agidi, Jeffrey T LejeuneAbstract:Aims: To type the staphylococcal cassette chromosome (SCC) in coagulase-negative staphylococci (CoNS) from animal sources. Methods and Results: A total of 92 CoNS isolates recovered from farm animals was analysed. The top three staphylococcal species were Staphylococcus Lentus (34), S. sciuri (31), and S. xylosus (13). The presence of the cassette chromosome recombinase (ccr) genes ccrA1, ccrB1, ccrA2, ccrB2, ccrA3, ccrB3 and ccrC, the mec regulatory genes mecI and mecR1, and Tn554 was used to differentiate the SCC. A total of 60 of the 92 isolates were methicillin resistant. Among the 60 methicillin-resistant Staphylococcus spp. isolates, SCCmec (mecA-carrying SCC) types I, III, IV and V were identified in 24 isolates based on the combinations of the ccr genes and the mec regulatory genes, with type III being predominant. The single S. epidermidis carried SCCmec type IV. SCC type III was also identified in two of 32 methicillin-susceptible isolates. Identical SCCmec types were present in different species of CoNS. Pulsed-field gel electrophoresis (PFGE) generated 64 patterns out of 81 PFGE typeable isolates. Indistinguishable clones were detected in animals from different farms. Conclusions: Heterogeneous SCC existed in CoNS of diverse genetic background. Both clonal transmission of methicillin-resistant CoNS and horizontal transfer of SCCmec occurred in the animal production environment. Significance and Impact of the Study: This study adds to our knowledge of SCCmec type and the diversity of SCC in CoNS.
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diversity of staphylococcal cassette chromosome in coagulase negative staphylococci from animal sources
Journal of Applied Microbiology, 2009Co-Authors: Y Zhang, S Agidi, Jeffrey T LejeuneAbstract:Aims: To type the staphylococcal cassette chromosome (SCC) in coagulase-negative staphylococci (CoNS) from animal sources. Methods and Results: A total of 92 CoNS isolates recovered from farm animals was analysed. The top three staphylococcal species were Staphylococcus Lentus (34), S. sciuri (31), and S. xylosus (13). The presence of the cassette chromosome recombinase (ccr) genes ccrA1, ccrB1, ccrA2, ccrB2, ccrA3, ccrB3 and ccrC, the mec regulatory genes mecI and mecR1, and Tn554 was used to differentiate the SCC. A total of 60 of the 92 isolates were methicillin resistant. Among the 60 methicillin-resistant Staphylococcus spp. isolates, SCCmec (mecA-carrying SCC) types I, III, IV and V were identified in 24 isolates based on the combinations of the ccr genes and the mec regulatory genes, with type III being predominant. The single S. epidermidis carried SCCmec type IV. SCC type III was also identified in two of 32 methicillin-susceptible isolates. Identical SCCmec types were present in different species of CoNS. Pulsed-field gel electrophoresis (PFGE) generated 64 patterns out of 81 PFGE typeable isolates. Indistinguishable clones were detected in animals from different farms. Conclusions: Heterogeneous SCC existed in CoNS of diverse genetic background. Both clonal transmission of methicillin-resistant CoNS and horizontal transfer of SCCmec occurred in the animal production environment. Significance and Impact of the Study: This study adds to our knowledge of SCCmec type and the diversity of SCC in CoNS.
Jeffrey T Lejeune - One of the best experts on this subject based on the ideXlab platform.
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diversity of staphylococcal cassette chromosome in coagulase negative staphylococci from animal sources
Journal of Applied Microbiology, 2009Co-Authors: Y Zhang, S Agidi, Jeffrey T LejeuneAbstract:Aims: To type the staphylococcal cassette chromosome (SCC) in coagulase-negative staphylococci (CoNS) from animal sources. Methods and Results: A total of 92 CoNS isolates recovered from farm animals was analysed. The top three staphylococcal species were Staphylococcus Lentus (34), S. sciuri (31), and S. xylosus (13). The presence of the cassette chromosome recombinase (ccr) genes ccrA1, ccrB1, ccrA2, ccrB2, ccrA3, ccrB3 and ccrC, the mec regulatory genes mecI and mecR1, and Tn554 was used to differentiate the SCC. A total of 60 of the 92 isolates were methicillin resistant. Among the 60 methicillin-resistant Staphylococcus spp. isolates, SCCmec (mecA-carrying SCC) types I, III, IV and V were identified in 24 isolates based on the combinations of the ccr genes and the mec regulatory genes, with type III being predominant. The single S. epidermidis carried SCCmec type IV. SCC type III was also identified in two of 32 methicillin-susceptible isolates. Identical SCCmec types were present in different species of CoNS. Pulsed-field gel electrophoresis (PFGE) generated 64 patterns out of 81 PFGE typeable isolates. Indistinguishable clones were detected in animals from different farms. Conclusions: Heterogeneous SCC existed in CoNS of diverse genetic background. Both clonal transmission of methicillin-resistant CoNS and horizontal transfer of SCCmec occurred in the animal production environment. Significance and Impact of the Study: This study adds to our knowledge of SCCmec type and the diversity of SCC in CoNS.
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diversity of staphylococcal cassette chromosome in coagulase negative staphylococci from animal sources
Journal of Applied Microbiology, 2009Co-Authors: Y Zhang, S Agidi, Jeffrey T LejeuneAbstract:Aims: To type the staphylococcal cassette chromosome (SCC) in coagulase-negative staphylococci (CoNS) from animal sources. Methods and Results: A total of 92 CoNS isolates recovered from farm animals was analysed. The top three staphylococcal species were Staphylococcus Lentus (34), S. sciuri (31), and S. xylosus (13). The presence of the cassette chromosome recombinase (ccr) genes ccrA1, ccrB1, ccrA2, ccrB2, ccrA3, ccrB3 and ccrC, the mec regulatory genes mecI and mecR1, and Tn554 was used to differentiate the SCC. A total of 60 of the 92 isolates were methicillin resistant. Among the 60 methicillin-resistant Staphylococcus spp. isolates, SCCmec (mecA-carrying SCC) types I, III, IV and V were identified in 24 isolates based on the combinations of the ccr genes and the mec regulatory genes, with type III being predominant. The single S. epidermidis carried SCCmec type IV. SCC type III was also identified in two of 32 methicillin-susceptible isolates. Identical SCCmec types were present in different species of CoNS. Pulsed-field gel electrophoresis (PFGE) generated 64 patterns out of 81 PFGE typeable isolates. Indistinguishable clones were detected in animals from different farms. Conclusions: Heterogeneous SCC existed in CoNS of diverse genetic background. Both clonal transmission of methicillin-resistant CoNS and horizontal transfer of SCCmec occurred in the animal production environment. Significance and Impact of the Study: This study adds to our knowledge of SCCmec type and the diversity of SCC in CoNS.
Corinna Kehrenberg - One of the best experts on this subject based on the ideXlab platform.
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florfenicol chloramphenicol exporter gene fexa is part of the novel transposon tn558
Antimicrobial Agents and Chemotherapy, 2005Co-Authors: Corinna Kehrenberg, Stefan SchwarzAbstract:The florfenicol-chloramphenicol exporter gene fexA is part of the novel transposon Tn558 from Staphylococcus Lentus. Similarities between Tn558 and Tn554 from Staphylococcus aureus included the arrangement of the transposase genes tnpA to -C and an att554-like target sequence. Circular forms of Tn558 were detected and suggest the functional activity of this transposon.
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fexa a novel Staphylococcus Lentus gene encoding resistance to florfenicol and chloramphenicol
Antimicrobial Agents and Chemotherapy, 2004Co-Authors: Corinna Kehrenberg, Stefan SchwarzAbstract:The Staphylococcus Lentus plasmid pSCFS2 carries a novel florfenicol-chloramphenicol resistance gene, designated fexA, encoding a protein of 475 amino acids with 14 transmembrane domains. The FexA protein differs from all previously known proteins involved in the efflux of chloramphenicol and florfenicol. Induction of fexA expression by chloramphenicol and florfenicol occurs via translational attenuation.
Joana Azeredo - One of the best experts on this subject based on the ideXlab platform.
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phage control of dual species biofilms of pseudomonas fluorescens and Staphylococcus Lentus
Biofouling, 2010Co-Authors: Sanna Sillankorva, Peter Neubauer, Joana AzeredoAbstract:Despite the recent enthusiasm for using bacteriophages as bacterial control agents, there are only limited studies concerning phage interaction with their respective hosts residing in mixed biofilm consortia and especially in biofilms where the host species is a minor constituent. In the present work, a study was made of mono and dual species biofilms formed by Pseudomonas fluorescens (Gram-negative) and/or Staphylococcus Lentus (Gram-positive) and their fate after infection with phages. The dual species biofilms consisted predominantly of S. Lentus. The exposure of these biofilms to a cocktail containing both P. fluorescens and S. Lentus phages effectively killed and removed the hosts from the substratum. Additionally, this cocktail approach also controlled the hosts released from the biofilms to the planktonic phase. The ability of phages to control a host population present in minority in the mixed species biofilm was also assessed. For this objective, the biofilms were challenged only with phage φIBB-...