1. Effect of antibiotics on redox transformations of arsenic and diversity of arsenite-oxidizing bacteria in sediment microbial communities.
- Author
-
Yamamura S, Watanabe K, Suda W, Tsuboi S, and Watanabe M
- Subjects
- Arsenic metabolism, Genes, Bacterial, Geologic Sediments microbiology, Oxidation-Reduction, Oxidoreductases genetics, Proteobacteria genetics, Proteobacteria metabolism, RNA, Ribosomal, 16S genetics, Anti-Bacterial Agents pharmacology, Arsenates metabolism, Arsenites metabolism, Chloramphenicol pharmacology, Proteobacteria drug effects, Water Pollutants, Chemical metabolism
- Abstract
In the present study, we investigated the effect of antibiotics on microbial arsenate (As(V)) reduction and arsenite (As(III)) oxidation in sediments collected from a small pond and eutrophic lake. The As(V)-reducing activities were less susceptible to chloramphenicol in aerobic conditions than in anaerobic conditions. Aerobic As(V) reduction proceeded in the presence of diverse types of antibiotics, suggesting that As-resistant bacteria are widely antibiotic resistant. In contrast, some antibiotics, e.g., chloramphenicol, strongly inhibited aerobic As(III) oxidation. In addition, bacterial As(III) oxidase genes were scarcely amplified and Proteobacteria -related 16S rRNA genes drastically decreased in chloramphenicol-amended cultures. Erythromycin and lincomycin, which successfully target many Gram-positive bacteria, scarcely affected As(III) oxidation, although they decreased the diversity of As(III) oxidase genes. These results indicate that the aerobic As(III) oxidizers in the sediment cultures are mainly composed of Proteobacteria and are more sensitive to certain types of antibiotics than the aerobic As(V) reducers. Our results suggest that antibiotic disturbance of environmental microbial communities may affect the biogeochemical cycle of As.
- Published
- 2014
- Full Text
- View/download PDF