Widely distributed unicellular or multicellular bacteria. The CYANOBACTERIA use chlorophyll a and phycobilins for oxygenic photosynthesis while genera in the Prochlorales use both chlorophyll a and b but not phycobilins.

One of the three domains of life (the others being Eukarya and ARCHAEA), also called Eubacteria. They are unicellular prokaryotic microorganisms which generally possess rigid cell walls, multiply by cell division, and exhibit three principal forms: round or coccal, rodlike or bacillary, and spiral or spirochetal. Bacteria can be classified by their response to OXYGEN: aerobic, anaerobic, or facultatively anaerobic; by the mode by which they obtain their energy: chemotrophy (via chemical reaction) or PHOTOTROPHY (via light reaction); for chemotrophs by their source of chemical energy: CHEMOLITHOTROPHY (from inorganic compounds) or chemoorganotrophy (from organic compounds); and by their source for CARBON; NITROGEN; etc.; HETEROTROPHY (from organic sources) or AUTOTROPHY (from CARBON DIOXIDE). They can also be classified by whether or not they stain (based on the structure of their CELL WALLS) with CRYSTAL VIOLET dye: gram-negative or gram-positive.

Bacteria which lose crystal violet stain but are stained pink when treated by Gram's method.

A genus of gram-negative, rod-shaped, phototrophic bacteria found in aquatic environments. Internal photosynthetic membranes are present as lamellae underlying the cytoplasmic membrane.

A genus of gram-negative, spiral bacteria that possesses internal photosynthetic membranes. Its organisms divide by binary fission, are motile by means of polar flagella, and are found in aquatic environments.

Vibrio- to spiral-shaped phototrophic bacteria found in stagnant water and mud exposed to light.

Spherical phototrophic bacteria found in mud and stagnant water exposed to light.

Pyrrole containing pigments found in photosynthetic bacteria.

A genus of gram-negative, ovoid to rod-shaped bacteria that is phototrophic. All species use ammonia as a nitrogen source. Some strains are found only in sulfide-containing freshwater habitats exposed to light while others may occur in marine, estuarine, and freshwater environments.

The synthesis by organisms of organic chemical compounds, especially carbohydrates, from carbon dioxide using energy obtained from light rather than from the oxidation of chemical compounds. Photosynthesis comprises two separate processes: the light reactions and the dark reactions. In higher plants; GREEN ALGAE; and CYANOBACTERIA; NADPH and ATP formed by the light reactions drive the dark reactions which result in the fixation of carbon dioxide. (from Oxford Dictionary of Biochemistry and Molecular Biology, 2001)

Non-pathogenic ovoid to rod-shaped bacteria that are widely distributed and found in fresh water as well as marine and hypersaline habitats.

Organelles of phototrophic bacteria which contain photosynthetic pigments and which are formed from an invagination of the cytoplasmic membrane.

Bacteria which retain the crystal violet stain when treated by Gram's method.

Infections caused by bacteria that show up as pink (negative) when treated by the gram-staining method.

A family of phototrophic bacteria, in the order Rhodospirillales, isolated from stagnant water and mud.

Proteins found in any species of bacterium.

Protein complexes that take part in the process of PHOTOSYNTHESIS. They are located within the THYLAKOID MEMBRANES of plant CHLOROPLASTS and a variety of structures in more primitive organisms. There are two major complexes involved in the photosynthetic process called PHOTOSYSTEM I and PHOTOSYSTEM II.

A family of phototrophic purple sulfur bacteria that deposit globules of elemental sulfur inside their cells. They are found in diverse aquatic environments.