Abstract
The effect of nickel on the microbial community in the activated sludge of a sequencing batch reactor (SBR) reactor was investigated by continuously dosing nickel from 60 to 240 mg Ni(II) L−1. The diversity of the microbial community was investigated by polymerase chain reaction (PCR) and denaturing gradient gel electrophoresis of the variable V3 region of the bacterial 16S rDNA. The experimental results showed that the community structure changed significantly after dosing with nickel with a shift in dominant species, the disappearance of some original species and the emergence of some new species. The existence of a nickel resistant gene was also investigated using PCR. The obtained nickel resistance gene had a maximum homology with the plasmid pMOL30 of Ralstonia metallidurans CH34. The quantitative real‐time PCR results indicated that the quantity of the nickel resistance gene was related to the nickel concentration loaded to the reactor.
Acknowledgements
Jia Li especially wishes to thank the Hong Kong General Research Fund (7195/06E) for research assistantship, and all the authors thank the Chinese Natural Science Foundation (No. 20377010), China High‐tech Research and Development (863) Plan (No. 2008AA062501), the Research Foundation of the Ministry of Environmental Protection of the People’s Republic of China (No.200809024) and The Foundation of the State Key Laboratory of Pollution Control and Resources Reuse (No. PCRRF09003) for financial support for this study.