Microbial community shift with decabromodiphenyl ether (BDE 209) in sediments of the Pearl River estuary, China

To compare the effect of decabromodiphenyl ether (BDE 209) on microbial community from the Pearl River estuary, the microbial community at three in situ sites and the responses of microbial community to BDE-209 stressor were investigated. Denaturing gradient gel electrophoresis analysis of 16S rRNA gene showed that microbial community at site A2 has less diversity than sites A1 and A3. Physicochemical parameters (NH4-N, salinity and SiO3-Si) could significantly impact the microbial community composition in this estuary. In laboratory-incubated experiments, results indicated high concentration of BDE 209 (100 mg/kg) could increase the microbial diversity at sites A1 and A2, whereas reduced the microbial diversity at site A3. The unweighted pair group method with arithmetic means cluster analysis and principal component analysis demonstrated that the community structure changes at sites A1 and A2 were driven by the BDE 209 concentration, whereas at site A3 they depended on the incubation time. Thirty-five days after the addition of 100 mg/kg BDE 209, Firmicutes were found to be the dominant bacteria at sites A1 and A2. These data suggest the BDE 209 may have different effects on the microbial community in the Pearl River estuary.