Antimicrobial Resistance Genes in Marine Bacteria and Human Uropathogenic Escherichia coli From a Region of Intensive Aquaculture
Microbiology and Immunology
Antimicrobials are heavily used in Chilean salmon aquaculture. We previously found significant differences in antimicrobial-resistant bacteria between sediments from an aquaculture and a non-aquaculture site. We now show that levels of antimicrobial resistance genes (ARG) are significantly higher in antimicrobial-selected marine bacteria than in unselected bacteria from these sites. While ARG in tetracycline- and florfenicol-selected bacteria from aquaculture and non-aquaculture sites were equally frequent, there were significantly more plasmid-mediated quinolone resistance genes per bacterium and significantly higher numbers of qnrB genes in quinolone-selected bacteria from the aquaculture site. Quinolone-resistant urinary Escherichia coli from patients in the Chilean aquacultural region were significantly enriched for qnrB (including a novel qnrB gene), qnrS, qnrA and aac(6')-1b, compared with isolates from New York City. Sequences of qnrA1, qnrB1 and qnrS1 in quinolone-resistant Chilean E. coli and Chilean marine bacteria were identical, suggesting horizontal gene transfer between antimicrobial-resistant marine bacteria and human pathogens.
Tomova, A., Ivanova, L., Buschmann, A., Rioseco, M., Kalsi, R., Godfrey, H., & Cabello, F. (2015). Antimicrobial Resistance Genes in Marine Bacteria and Human Uropathogenic Escherichia coli From a Region of Intensive Aquaculture. Environmental Microbiology Reports, 7 (5), 803-809. https://doi.org/10.1111/1758-2229.12327