Sulfur Bacteria

Anaerobic bacteria

Thought to be the endosymbiont group for eukaryotes, and the origin of the mitochondria

Filamentous

Photosynthetic

• Use bacteriochlorophyll a as well as bacteriochlorophylls c, d, or e

• Use hydrogen sulfide gas, instead of water, during the reduction process

  • 2H₂S (sulfide) + CO₂ ---> CH₂O (sugar)+ S₂ (sulfur) + H₂O

Sulfur is abundant in nature, but plants can only use sulfate

Hydrogen sulfide (H₂S) is toxic to aquatic flora and fauna

Sulfur anions (SO₄⁺) can make inorganic salts, such as phosphorous, available to plants

Sulfate prevents excessive alkalinity from ammonia produced by microorganisms

• Paleoproterozoic - present