Aquatic samples from three water bodies were collected following laid down procedures. The bacteria were isolated using, Eosin Methylene Blue agar (EMB), Mannitol salt agar (MSA), Thiosulfate-Citrate-Bile Salts-Sucrose (TCBS) Agar, Muller Hinton (MH). The isolates were subjected to colonial, morphological and biochemical characterization. Pathogenicity test was carried out on the isolates using blood agar to determine their hemolytic activities. Antibiotic resistance status was also investigated against standard antibiotics using the Kirby Bauer disk diffusion method and the multiple antibiotic resistance indices of the isolates were also determined. The plasmid profiles were determined and the resistance genes were identified using molecular means. The bacteria species isolated were Veillonella Spp, Vibrio orientalis and Micrococcus luteus. Veillonella Spp showed Beta hemolysis while Micrococcus luteus showed alpha hemolysis and Vibrio orientalis showed gamma hemolysis. Antibiotic susceptibility test showed all isolates to be antibiotic resistant to varying degrees and multiple antibiotic resistance indices (MARi) depending on their level of resistance. Veillonella. spp. had MARi of 0.3 while M. luteus and V. orietalis had MARi of 0.5. Plasmid profiling showed all isolates to have plasmids with bandwidth of 10,000 bp. Vibrio spp and Veillonella Spp were positive for beta lactamase genes (bla SHV). Only Vibrio was positive for resistance to aminoglycosides (aac(3)-IV). Vibrio orientalis and Micrococcus luteus were found to have the resistance genes for quinolones (qnrA gene) while all the isolates possess genes against the sulphonamides (sul1 gene) used. The result of this work establishes the antibiotic resistance status of bacteria isolated from aquatic habitat and suggests their important role in the spread of antimicrobial resistance AMR, and antibiotic resistance genes (ARGs).
Keywords: Antibiotic resistance genes, water bodies, hemolysis, plasmids profiles, aminoglycosides (aac(3)-, quinolones (qnrA gene), sulphonamides (sul1 gene) integrons, Primers