Bacterial Communities and Functional Genes Stimulated During Anaerobic Arsenite Oxidation and Nitrate Reduction in a Paddy Soil
Citations Over TimeTop 10% of 2019 papers
Abstract
Microbial arsenite (As(III)) oxidation associated with nitrate (NO3-) reduction might be an important process in diminishing arsenic bioavailability and toxicity to rice when paddy soils are contaminated by arsenic. In a noncontaminated soil, however, the responses of bacterial communities and functional genes to As(III) under nitrate-reducing conditions are poorly understood. In this study, anaerobic paddy soil microcosms were established with As(III) and/or NO3- to investigate how the bacterial communities and their functional genes were stimulated during As(III) oxidation and nitrate reduction. Microbial oxidation of As(III) to As(V) was substantially accelerated by nitrate addition, while nitrate reduction was not affected by As(III) addition. Metagenomic analysis revealed that nitrate-reducing bacteria were principally affiliated with Pseudogulbenkiania, with narG, nirS, and norBC genes. Putative As(III)-oxidizing bacteria were dominated by an Azoarcus sp. with As(III) oxidase genes aioA and aioB detected in its draft genome, which also had complete sets of denitrification genes (mainly, napA, nirK, and nosZ). Quantitive PCR analysis confirmed that the abundance of Azoarcus spp., aioA, and nosZ genes was enhanced by As(III) addition. These findings suggest the importance of Azoarcus- and Pseudogulbenkiania-related spp., both of which showed various physio-ecological characteristics for arsenic and nitrogen biogeochemistry, in coupling As(III) oxidation and nitrate reduction in flooded paddy soil.
Related Papers
- → Accumulation and Transformation of Arsenic in the Blue-Green Alga Synechocysis sp. PCC6803(2011)94 cited
- → Changes in the chemical speciation of arsenic following ingestion by man.(1977)329 cited
- → Arsenic compounds in leaves and roots of radish grown in soil treated by arsenite, arsenate and dimethylarsinic acid(2002)65 cited
- → Arsenic Removal and Biotransformation Potential of Exiguobacterium Isolated From an Arsenic‐Rich Soil of Chhattisgarh, India(2015)18 cited
- → Determination of arsenic compounds in human urine by HPLC-ICP-MS(1997)15 cited