title: Identification of antibiotic resistance cassettes in class 1 integrons in Aeromonas spp. strains isolated from fresh fish (Cyprinus carpio L.).
abstract: Forty-six Aeromonas spp. strains were isolated from fresh fish and investigated for their antimicrobial susceptibility, detection of Class 1 integrons by PCR, and arrangement of gene cassettes. Selected isolates were further characterized by enterobacterial repetitive intergenic consensus-PCR. Twenty isolates were found to carry Class 1 integrons. Amplification of the variable regions of the integrons revealed diverse bands ranging in size from 150 to 1,958 pb. Sequence analysis of the variable regions revealed the presence of several gene cassettes, such as adenylyl transferases (aadA2 and aadA5), dihydrofolate reductases (dfrA17 and dfrA1), chloramphenicol acetyl transferase (catB3), β-lactamase (oxa2), lincosamide nucleotidil transferase (linF), aminoglycoside-modifying enzyme (apha15), and oxacillinase (bla OXA-10). Two open reading frames with an unknown function were identified as orfC and orfD. The aadA2 cassette was the most common integron found in this study. Interestingly, five integrons were detected in the plasmids that might be involved in the transfer of resistance genes to other bacteria. This is a first report of cassette encoding for lincosamides (linF) resistance in Aeromonas spp. Implications on the incidence of integrons in isolates of Aeromonas spp. from fresh fish for human consumption, and its possible consequences to human health are discussed.
authors.affiliation: Laboratory of Soil Ecology, ABACUS, Cinvestav, Mexico, Mexico.
authors.forename: Yohanna
authors.initials: Y
authors.lastname: Sarria-Guzmán
authors.forename: María Patricia
authors.initials: MP
authors.lastname: López-Ramírez
authors.forename: Yosef
authors.initials: Y
authors.lastname: Chávez-Romero
authors.forename: Erick
authors.initials: E
authors.lastname: Ruiz-Romero
authors.forename: Luc
authors.initials: L
authors.lastname: Dendooven
authors.forename: Juan Manuel
authors.initials: JM
authors.lastname: Bello-López
mesh_terms: D000333:Aeromonas / Q000187:drug effects* / Q000235:genetics* / Q000302:isolation & purification; D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D002347:Carps / Q000382:microbiology*; D024881:Drug Resistance, Bacterial; D023061:Gene Order; D005798:Genes, Bacterial; D032023:Integrons; D008826:Microbial Sensitivity Tests; D016133:Polymerase Chain Reaction; D017422:Sequence Analysis, DNA
chemical_list: D000900:Anti-Bacterial Agents