Co-Prevalence of Virulence and Pathogenic Potential in Multiple Antibiotic Resistant <i>Aeromonas</i> spp. from Diseased Fishes with <i>In Silico</i> Insight on the Virulent Protein Network

Abstract

Aeromonas species exhibit widespread presence in food, poultry, and aquaculture. They are major multi-drug-resistant fish pathogens. This study aims to identify Aeromonas species harbouring virulence genes aerolysin, flagellin, and lipase from diseased fishes of Assam wetlands with association with antibiotic resistance and in vivo pathogenicity. One hundred and thirty-four Aeromonas strains were isolated and thirty representative species identified using genus-specific 16S rRNA gene amplification. A. veronii was most prevalent (53.7%) followed by A. hydrophila (40.2%), A. caviae (4.47%), and A. dhakensis (1.49%). Ninety percent (90%) of strains harboured at least one of the studied virulence genes: aerA (73.3%), lip (46.6%), and flaA (26.6%). The highest multiple antibiotic resistance (MAR) index 0.8 corresponded to A. hydrophila DBTNE1 (MZ723069), containing all the studied genes. The lowest LD50 values (1.6 × 106 CFU/fish) corresponded to isolates having both aerA and lip. β-lactams showed utmost resistance and lowest for aminoglycosides. There was a significant (p p Aeromonas strains represent potential threat to aquaculture with subsequent risk of transferring antibiotic resistance to human pathogens.

Keywords

• <i>Aeromonas</i>
• Assam wetland fisheries
• virulence gene
• antibiotic resistance
• pathogenesis
• protein–protein interaction