Patterns of microbial arsenic detoxification genes in low-arsenic continental paddy soils.

Abstract Microbes mediate the arsenic detoxification in paddy soils, determining the fate of arsenic in soils and its availability to rice plants, yet little is known about the structures and abundances of functional genes as well as the driving forces in low-arsenic paddy fields. To depict the arsenic detoxification functional gene patterns, 429 soil samples were collected from 39 paddy fields across four climatic zones in China, with the arsenic contents ranged from 9.76 to 19.74 mg kg−1. GeoChip, a microarray-based metagenomic technique, was used to analyze the functional genes involved in arsenic detoxification. A total of three arsenic detoxification gene families were detected, aoxB, arxA (arsenite oxidase), and arsM (methyltransferase). Both the diversity and abundance of functional genes varied significantly among sampling sites (p