Arsenite modifies structure of soil microbial communities and arsenite oxidization potential

作者：Lami Raphael; Jones L Camille; Cottrell Matthew T; Lafferty Brandon J; Ginder Vogel M; Sparks Donald L; Kirchman David L^*

来源：FEMS Microbiology Ecology, 2013, 84(2): 270-279.

DOI：10.1111/1574-6941.12061

• arsenite oxidation
• soil bacterial communities
• molecular approaches
• 16S rRNA pyrosequencing

The influence of arsenite [As(III)] on natural microbial communities and the capacity of exposed communities to oxidize As(III) has not been well explored. In this study, we conducted soil column experiments with a natural microbial community exposed to different carbon conditions and a continuous flow of As(III). We measured the oxidation rates of As(III) to As(V), and the composition of the bacterial community was monitored by 454 pyrosequencing of 16S rRNA genes. The diversity of As(III)-oxidizing bacteria was examined with the aox gene, which encodes the enzyme involved in As(III) oxidation. Arsenite oxidation was high in the live soil regardless of the carbon source and below detection in sterilized soil. In columns amended with 200molkg1 of As (III), As(V) concentrations reached 158molkg1 in the column effluent, while As(III) decreased to unmeasurable levels. Although the number of bacterial taxa decreased by as much as twofold in treatments amended with As(III), some As(III)-oxidizing bacterial groups increased up to 20-fold. Collectively, the data show the large effect of As(III) on bacterial diversity, and the capacity of natural communities from a soil with low initial As contamination to oxidize large inputs of As(III).

• 出版日期2013-5