Transcriptome Profiling of <i>Stenotrophomonas</i> sp. Strain WZN-1 Reveals Mechanisms of 2,2′,4,4′-Tetrabromodiphenyl Ether (BDE-47) Biotransformation

Abstract

The brominated flame retardant 2,2',4,4'-tetrabromodiphenyl ether (BDE-47) is extensively used, stable, and difficult to degrade in the environment. The existence of BDE-47 could pose a certain risk to the environment and human health. However, the biotransformation mechanisms of BDE-47 by microorganisms remain unclear. In this study, aerobic degradation of BDE-47 by <i>Stenotrophomonas</i> sp. strain WZN-1 and transcriptome analysis were carried out. BDE-47 degradation by <i>Stenotrophomonas</i> sp. strain WZN-1 was mainly through the biological action of intracellular enzymes via the route of debromination and hydroxylation. The results of the transcriptome sequencing indicated the differentially expressed genes were related to transport, metabolism, and stress response. The key processes involved the microbial transmembrane transportation of BDE-47, energy anabolism, synthesis, and metabolism of functional enzymes, stress response, and other biological processes of gene regulation. In particular, bacterial chemotaxis played a potential role in biodegradation of BDE-47 by <i>Stenotrophomonas</i> sp. strain WZN-1. This study provides the first insights into the biotransformation of <i>Stenotrophomonas</i> sp. strain WZN-1 to BED-47 stress and shows potential for application in remediation of polluted environments.