sulfatreducers

Sulfate-reducing bacteria, often abbreviated as SRBs, are a group of microorganisms belonging to the domain Bacteria. They are characterized by their ability to perform anaerobic respiration, using sulfate (SO4^2-) as the terminal electron acceptor instead of oxygen. This process results in the reduction of sulfate to sulfide (S^2-). This metabolic capability is found in a diverse range of bacterial phyla.

SRBs play significant roles in various natural and anthropogenic environments. In anaerobic environments such as marine sediments, waterlogged soils, and the digestive tracts of animals, they are important in the sulfur cycle. Their activity can lead to the formation of hydrogen sulfide, a gas with a characteristic rotten egg smell. This hydrogen sulfide can be further oxidized by other microorganisms, completing the sulfur cycle.

The sulfide produced by SRBs can have both beneficial and detrimental effects. In some ecosystems, it is a vital nutrient source. However, in industrial settings, SRBs can cause problems. For instance, they are implicated in microbiologically influenced corrosion (MIC) of metals, particularly in pipelines carrying water or oil, due to the corrosive nature of sulfide. They can also contribute to reservoir souring in the oil and gas industry, increasing the hydrogen sulfide content of extracted hydrocarbons. Despite these challenges, SRBs are also utilized in some biotechnological applications, such as bioremediation and the production of certain bioproducts.