Evolution and Ecology of Microbes Dissimilating Sulfur Compounds: Insights from Siroheme Sulfite Reductases

Abstract

Sulfur microorganisms have been thriving on Earth since the dawn of life and are still of central importance for the functioning of modern ecosystems. Here, we summarize the current perception of the evolution of dissimilatory siroheme sulfite reductases (DSRs), antique key enzymes in the energy metabolism of sulfur microbes. We further give recent examples of the diversity and ecology of uncultured sulfur-dissimilating microorganisms; unprecedented insights that were only made possible by exploiting DSR-encoding genes as molecular markers in environmental surveys.