Comparative genomics reveals virulent lineages of Shewanella and their evolution

CECILIA QUIROGA; GABRIELA CERBINO; ANDRÉS IRIARTE

Virtual

Simposio; #UnityInDiversity; 2020

ISME

Shewanella spp. are gram-negative bacteria that thrive in aquatic environments and can be used for bioremediation and microbial fuel cells. Some species encode ubiquitously carbapenem or quinolone resistance genes (blaOXA-48; qnr). The increase in multidrug resistance (MDR) in Shewanella isolated from clinical settings suggest they have become emergent opportunistic pathogens. Little is known about the genetic traits that contribute in their adaptation and pathogenicity. The aim of this study was to undertake a comparative genome analysis to identify accessory genes related to MDR, virulence and horizontal gene transfer, in order to unravel their genome evolution. We built a phylogenomic tree using orthologous genes of 145 Shewanella available genomes and calculated their ANI, which allowed us to identify virulent lineages. S. algae and S. xiamenensis lineages contained antimicrobial resistance genes (AGR) ubiquitous at species level and clinical samples harboring > than 5 ARGs. Species from niches with less anthropic impact did not encode known resistance genes (p