Anais do Congresso Paranaense de Microbiologia
Anais do IV Congresso Paranaense de Microbiologia

The presence of multidrug-resistant (MDR) bacteria harboring antimicrobial resistance genes (ARGs) and metal tolerance genes (MTGs) in recreational areas has caused concerns worldwide. Due to the presence of potentially pathogenic bacteria associated with the high flow of people in recreational areas, some countries carry out the monitoring of bacteria in water and sand samples from urban beaches; however, Pseudomonas sp., especially Pseudomonas aeruginosa, are not monitored even being considered as one of the most opportunistic pathogens associated with multidrug resistance phenotype. Therefore, the aim of this study was to characterize Pseudomonas sp. recovered from environmental samples regarding their antimicrobial resistance and metal tolerance profiles, as well as genes associated with these profiles. The water and sand samples were inoculated in a selective and differential medium for bacteria of the genus Pseudomonas. Afterward, molecular identification was performed by conventional PCR using specific primers to confirm the genus Pseudomonas, and the species P. aeruginosa and Pseudomonas fluorescens. The minimal inhibitory concentration (MIC) was determined using the agar dilution method to determine the antimicrobial resistance and metal tolerance profiles. ARGs were detected by conventional PCR. A total of 20 isolates of Pseudomonas sp. was obtained (11 from waters and 9 from sands), whose molecular identification showed 12 P. aeruginosa, 6 P. fluorescens, and two were not identified using species-specific primers. The isolates presented MICs ranging from 1 to 256 mg/L, being 17 classified as MDR. Metal tolerance ranged from 0.6 to 50mmol/L, highlighting high concentrations for copper and cobalt. The ARGs qnrS, oqxA, oqxB, tet(C), tet(D), tet(G), blaCTX-M-Gp9, blaVEB, and blaSHV, and MTGs silA and arsB, were found. These results call attention to the dissemination of Pseudomonas sp. exhibiting multidrug resistance and metal tolerance phenotypes, as well as carrying different genes related to these profiles, in urban beaches in Brazil.