Electron shuttles facilitate methane-dependent arsenate reduction in paddy soils.

Ouyuan Jiang; Yichang Wang; Xiaochao Yuan; Li Dai; Xinyu Zhao; Buran Zhang; Zhongjian Li; Xianjin Tang

doi:10.1016/j.jes.2026.01.074

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Electron shuttles facilitate methane-dependent arsenate reduction in paddy soils.

Ouyuan Jiang·Yichang Wang·Xiaochao Yuan·Li Dai·Xinyu Zhao·Buran Zhang·Zhongjian Li·Xianjin Tang

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Abstract

Methane-dependent arsenate reduction (M-AsR) occurs widely in paddy soils and can substantially enhance arsenic mobilization, posing potential ecological risks. However, the role of electron shuttles in this process remains poorly understood. In this study, we investigated the influence of anthraquinone-2,6-disulfonate (AQDS) on M-AsR in paddy soils. Fourteen-day incubation showed that 1 mmol/L AQDS facilitated 50.88 % of arsenate reduction and 31.31 % of methane oxidation. Quantitative polymerase chain reaction analysis revealed that AQDS significantly increased the abundance of functional genes associated with arsenate reduction (arrA, arsC) and anaerobic methane oxidation (mcrA) (P < 0.05). Microbial community analysis revealed that AQDS addition enriched Cloacibacterium, Sphingorhabdus, and Methylocystis, while decreasing the relative abundance of Methylobacter and Methylomonas. These findings indicate that electron shuttles facilitate M-AsR by modulating functional microbial populations, providing valuable insights into arsenic biogeochemistry and the coupled cycling of methane and arsenic in paddy soils.

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Methane Arsenates Soil Pollutants Soil Microbiology Soil Oxidation-Reduction Oryza Anthraquinone-2,6-disulfonate (AQDS)Arsenic Electron shuttles Methane oxidation Paddy soil Journal Article

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Ouyuan Jiang, Yichang Wang, Xiaochao Yuan, Li Dai, Xinyu Zhao, Buran Zhang, Zhongjian Li, Xianjin Tang. 2026-01-30. Electron shuttles facilitate methane-dependent arsenate reduction in paddy soils.. https://doi.org/10.1016/j.jes.2026.01.074

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