Genome sequencing and annotation of multi-virulent Aeromonas veronii XhG1.2 isolated from diseased Xiphophorus hellerii.

Abstract

The present study was intended to elucidate the genomic basis of antibiotic resistance and hyper-virulence of the fish pathogen Aeromonas veronii XhG1.2 characterized in our previous work. The identity of XhG1.2 was confirmed through 16S rDNA sequence analysis and whole genome sequence analysis. The top-hit species distribution analysis of XhG1.2 sequence data revealed major hits against the Aeromonas veronii. The identification of virulence genes using the VFDB showed the genome of XhG1.2 to have the genes coding for the virulence factors viz. aerolysin, RtxA, T2SS, T3SS and T6SS. The presence of antibiotic resistance predicted through the CARD database analysis showed it to have the CephA3, OXA-12, adeF and pulvomycin resistance genes. By the phylogenetic and comparative genomic analysis, A. veronii species were found to have genes for toxin production. This also confirmed the pathogenicity and drug resistance of A. veronii XhG1.2 and also its potential to cause disease in diverse ornamental fishes.