Determination of Pathogenicity of Bacteria Isolated from Some Aquatic Amphibian and Reptile Species

Abstract

Microflora of reptiles and amphibians pose a serious threat to the environment and humans, as these bacteria are more resistant to antimicrobials or have more virulence factors. In this study, we focused on the characterization of Gram-negative bacterial isolates obtained from Mauremys rivulata (Western Caspian turtle), Natrix natrix (Grass snake), Natrix tessellata (Dice snake) and Pelophylax bedriagae (Levantine frog) using cultural methods and determine some virulence factors (antibiotic resistance, VanA and TetM resistant genes, biofilm, siderophore and some enzymatic activities etc.). Multiple antibiotic resistance (MAR) and virulence index (VI) of each strain were also calculated. A total of 85 Gram-negative isolates exhibited varying levels of antibiotic resistance and the ability to produce one or more extracellular enzymes such as amylase, lecithinase, protease, lipase, hemolysis, siderophore, amino acid decarboxylase and DNase. Although the TetM has been identified in all 7 isolates, none of the isolates have shown the presence of the VanA gene. According to MAR and VI results, most of the isolates were found to be in the high threat group and these indexes were correlated with antibiotic resistance. The study data revealed that chemicals used in industry and agriculture both trigger environmental pollution and pose risk factors for wildlife.