Autotrophic prokaryotes derive all their carbon from inorganic sources, and photoautotrophs utilize light energy (anaerobic Chromatium movie and aerobic Cyanobacteria). Some prokaryotes are heterotrophic, utilizing organic substance as a source of carbon, and the purple and green photosynthetic bacteria obtain energy from light (Rhodospirillum rubrum movie).
Photosynthetic bacteria include: Cyanobacteria, green filamentous, green sulfur, prochlorophytes, purple sulfur, and purple nonsulfur bacteria.
Oxygenic photosynthesis, utilizing H2O as electron donor : Cyanobacteria, prochlorophytes. The Cyanobacteria, of course, are considered both the stimulus for and the endosymbionts in chloroplasts.
Nonoxygenic photosynthesis utilizing S– or So or H2 as electron donor:green filamentous, green sulfur, purple sulfur, and purple nonsulfur