ABSTRACT
Fluoroquinolone resistance was characterized in Escherichia coli O78:K80 isolated from diseased turkeys. The level of resistance to fluoroquinolones of the isolates appeared closely correlated with substitutions in GyrA and ParC, but not with the production of the AcrAB efflux pump. Among isolates highly resistant to ciprofloxacin (MIC 8 mg/L) and harbouring identical substitutions (two in GyrA and one in ParC), two close but distinguishable ribotypes were identified. This indicated that at least two independent selection events may have occurred.
Subject(s)
Anti-Infective Agents/pharmacology , Carrier Proteins , Drug Resistance, Microbial , Escherichia coli Proteins , Escherichia coli/drug effects , Fluoroquinolones , Turkeys/microbiology , Amino Acid Substitution , Animals , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Blotting, Western , Ciprofloxacin/pharmacology , DNA Gyrase , DNA Topoisomerase IV , DNA Topoisomerases, Type II/genetics , DNA, Bacterial/genetics , DNA-Binding Proteins/genetics , Enrofloxacin , Escherichia coli/genetics , Escherichia coli/isolation & purification , Lipoproteins/metabolism , Membrane Proteins/metabolism , Membrane Transport Proteins , Microbial Sensitivity Tests , Multidrug Resistance-Associated Proteins , Mutation , Nalidixic Acid/pharmacology , Quinolizines/pharmacology , Quinolones/pharmacology , RNA, Ribosomal, 16S/genetics , RNA, Ribosomal, 23S/geneticsABSTRACT
A florfenicol resistance gene almost identical to floR of Salmonella enterica serovar Typhimurium DT104 was detected on 110- to 125-kb plasmids in Escherichia coli isolates of animal origin. Analysis of the floR gene flanking regions of one of the plasmids showed that they were different from those encountered in S. enterica serovar Typhimurium DT104.
Subject(s)
Cattle Diseases/microbiology , Escherichia coli Infections/microbiology , Escherichia coli Infections/veterinary , Escherichia coli/enzymology , Escherichia coli/genetics , Genes, Bacterial/genetics , Plasmids/genetics , Thiamphenicol/analogs & derivatives , Animals , Cattle , Dogs , Drug Resistance, Microbial , Molecular Sequence Data , Reverse Transcriptase Polymerase Chain Reaction , Sheep , Thiamphenicol/pharmacologyABSTRACT
Recently a chromosomal locus possibly specific for Salmonella enterica serovar Typhimurium DT104 has been reported that contains a multiple antibiotic resistance gene cluster. Evidence is provided that Salmonella enterica serovar Agona strains isolated from poultry harbor a similar gene cluster including the newly described floR gene, conferring cross-resistance to chloramphenicol and florfenicol.
Subject(s)
Drug Resistance, Microbial/genetics , Multigene Family , Salmonella enterica/genetics , Animals , Chloramphenicol/pharmacology , Drug Resistance, Multiple/genetics , Genome, Bacterial , Poultry/microbiology , Salmonella enterica/drug effects , Thiamphenicol/analogs & derivatives , Thiamphenicol/pharmacologyABSTRACT
Twenty-three strains of Ornithobacterium rhinotracheale from various origins, associated with respiratory pathology of birds, were compared using plasmid profiles, ribotyping and Random Amplified Polymorphic DNA (RAPD) in order to achieve a precise strain characterization as well as to highlight the relationships between these strains. No plasmid could be detected. These strains were poorly discriminated by ribotyping although different enzymes were used. The RAPD analysis has given reproducible DNA fingerprints and a good level of discrimination. This method can be used with only one or two primers to differentiate the O. rhinotracheale strains and could be used in epidemiological studies.
