Representative Bacillus sp. AM1 from Gut Microbiota Harbor Versatile Molecular Pathways for Bisphenol A Biodegradation

Abstract

Human gut microbiota harbors numerous microbial species with molecular enzymatic potential that impact on the eubiosis/dysbiosis and health/disease balances. Microbiota species isolation and description of their specific molecular features remain largely unexplored. In the present study, we focused on the cultivation and selection of species able to tolerate or biodegrade the endocrine disruptor bisphenol A (BPA), a xenobiotic extensively found in food plastic containers. Chemical xenobiotic addition methods for the directed isolation, culturing, Whole Genome Sequencing (WGS), phylogenomic identification, and specific gene-encoding searches have been applied to isolate microorganisms, assess their BPA metabolization potential, and describe encoded catabolic pathways. BPA-tolerant strains were isolated from 30% of infant fecal microbial culture libraries analyzed. Most isolated strains were phylogenetically related to the operational taxonomic group Bacillus amyloliquefaciens spp. Importantly, WGS analysis of microbial representative strain, Bacillus sp. AM1 identified the four complete molecular pathways involved on BPA degradation indicating its versatility and high potential to degrade BPA. Pathways for Exopolysaccharide (EPS) and Polyhydroxyalkanates (PHA) biopolymer synthesis were also identified and phenotypically confirmed by transmission electronic microscopy (TEM). These microbial biopolymers could generally contribute to capture and/or deposit xenobiotics.