Shedding Light on the Bacterial Resistance to Toxic UV Filters: A Comparative Genomic Study

Abstract

Background: UV filters are toxic to marine bacteria that dominate the marine biomass. Ecotoxicology often studies the organismal response but rarely integrates deciphers the toxicity mechanisms at the molecular level. In this study, in silico comparative genomic between UV filters sensitive and resistant bacteria were conducted in order to unravel the genes responsible for a resistance phenotype. The genomes of two environmentally relevant Bacteroidetes and three Firmicutes species were compared through pairwise comparisonResults: Larger genomes were carried by bacteria exhibiting a resistant phenotype, favoring their ability to adapt to environmental stresses. While the antitoxin and CRISPR systems were the only distinctive features in resistant Bacteroidetes, Firmicutes displayed multiple unique genes that could support the difference between sensitive and resistant phenotypes.Conclusion: Several genes involved in ROS response, vitamin biosynthesis, xenobiotic degradation, multidrug resistance, xenobiotic degradation, and lipophilic compound permeability were shown to be exclusive to resistant species. Our investigation contributes to a better understanding of the molecular basis of UV filters resistance phenotypes.