Pseudomonas aeruginosa is an important water-borne and food-borne pathogen, which is easy to cause infection when the body′s immunity declines. Understanding the resistance and pathogenicity of P. aeruginosa is of great significance for the prevention and control of infection of P. aeruginosa. To investigate the resistance of P. aeruginosa isolated from Three Gorges Reservoir and its pathogenicity against Caenorhabditis elegans, bacteria were isolated from water samples collected from Three Gorges Reservoir. P. aeruginosa was screened out by morphological identification, physiological and biochemical identification, 16S rDNA sequencing and oprI specific gene identification. Drug resistance, resistance genes and virulence genes of the isolates were studied, and the model organism C. elegans was used for toxicological evaluation. The results showed that 14 strains of P. aeruginosa were isolated and identified from the Three Gorges Reservoir. The isolates were resistant to penicillin G, ampicillin, cefazolin, kanamycin and erythromycin, and sensitive to amikacin, gentamicin, norfloxacin, ciprofloxacin, meropenem and levofloxacin. The resistance genes bla TEM, aac (6′)-II, qacΔ1-sull, qnrS, mexR were positive in all isolates. Drug resistance genes aac(3)-Ⅰ, tetA, tetB, tetD, tetE, cat, cmlA, qnrA, qnrD were negative in all isolates. In addition, the isolates carried multiple virulence genes. After infection with isolates PA7, PA8 and PA12, the average lifespan of C. elegans decreased by 15%, 14%, and 16% respectively (P<0.05), and body bending frequency of decreased by 18%, 33% and 23% respectively (P<0.05), and head swing frequency of decreased by 10%, 13% and 11% respectively (P<0.05), and the longest lifespan was shortened by about 3 days. The results showed that the isolates of P. aeruginosa in the Three Gorges Reservoir had multiple drug resistance, and some of the isolates were pathogenic to C. elegans, which could provide some reference for the prevention and control of P. aeruginosa infection in water. |