Arsenic is the most prevalent environmental toxic element and causes health problems throughout the world. The toxicity, mobility, and fate of arsenic in the environment are largely determined by its speciation, and arsenic speciation changes are driven, at least to some extent, by biological processes. In this article, biotransformation of arsenic is reviewed from the perspective of the formation of Earth and the evolution of life, and the connection between arsenic geochemistry and biology is described. The article provides a comprehensive overview of molecular mechanisms of arsenic redox and methylation cycles as well as other arsenic biotransformations. It also discusses the implications of arsenic biotransformation in environmental remediation and food safety, with particular emphasis on groundwater arsenic contamination and arsenic accumulation in rice.

中文翻译：

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地球上存在砷的生物转化

砷是最普遍的环境有毒元素，在全世界范围内引起健康问题。砷在环境中的毒性、迁移性和归宿很大程度上取决于其形态，而砷形态的变化至少在某种程度上是由生物过程驱动的。本文从地球形成和生命演化的角度综述了砷的生物转化，并阐述了砷地球化学与生物学的联系。该文章全面概述了砷氧化还原和甲基化循环以及其他砷生物转化的分子机制。它还讨论了砷生物转化对环境修复和食品安全的影响，特别强调地下水砷污染和稻米中的砷积累。