Purple sulfur bacteria Purple sulfur bacteria The purple sulfur bacteria (PSB) are part of a group of Proteobacteria capable of photosynthesis, collectively referred to as purple bacteria. They are anaerobic or microaerophilic, and are often found in stratified water environments including hot springs, stagnant water bodies, as well as microbial mats in intertidal zones. Unlike plants, algae, and cyanobacteria, purple sulfur bacteria do not use water as their reducing agent, and therefore do not produce oxygen. Instead, they can use sulfur in the form of sulfide, or thiosulfate (as well, some species can use H, Fe, or NO) as the electron donor in
Leucothrix (bacteria) Leucothrix (bacteria) Leucothrix is a genus of large, filamentous bacteria, which live as epiphytes in marine habitats. "Leucothrix" Oersted, 1844 is the type genus of the family Leucothricaceae Buchanan, 1957, but has also been classified in the family Thiotrichaceae (Gammaproteobacteria). There are two species described, "L. mucor" Oersted, 1844 (type species) and "L. pacifica" Zhang et al., 2015. "Leucothrix" is a large bacterium that forms filaments between 2-3 µm wide and up to 0.5 cm in length. They are usually found as epiphytes on marine plants and algae, but also grow attached to other surfaces like the shells of crustaceans.