Microbial Bioenergetics and Ecology Govern the Coupled Biogeochemical Cycling of Arsenic/Antimony and Macronutrients

However, the mechanistic basis of these coupled processes remains poorly understood. In this Review, we synthesize current advances in the interconnected cycling and elucidate their thermodynamic and ecological foundations.

Redox-sensitive As, Sb, C, N, and S species serve as electron donors and acceptors in microbial respiratory chains, and the combination of their redox half-reactions results in the coupled cycles. A redox-ladder framework delineates the theoretical electron flow and thermodynamically feasible coupling combinations. Many combinations have been observed in the environments-for instance, NO₃^– reduction to N₂ coupled with As(III)/Sb(III) oxidation.