Controls on Isotope Fractionation During Dissimilatory Sulfate Reduction

Abstract

Sulfur isotopes are fractionated during dissimilatory sulfate reduction; therefore, sulfur isotope studies have been useful in elucidating the role of sulfate reduction in the sulfur cycle, and in understanding the early evolution of the sulfur metabolism on Earth. Sulfur isotope fractionation during sulfate reduction occurs when sulfate is transported into the cell and is reduced to sulfide through a series of reversible reactions operating with different efficiencies and distinct fractionation factors.