The Main Groups of Photosynthetic Bacteria and Photosynthetic Pigments

Abstract

Photosynthesis is one of the most important process on today’s Earth, which provides most of the energy source of the Earth’s biosphere, changed and shaped the atmosphere and oceans in early days of the Earth. Photosynthetic bacteria are a kind of prokaryotic microorganism that can assimilate or dissimilate by using light energy as an energy source and organic or inorganic matter as the electron donor for assimilation or heterocytosis, which can be divided into Cyanobacteria, Purple bacteria (PB), Green bacteria (GB), Aerobic anoxygenic photosynthesis bacteria (AAPB) and others. In this paper, the literature on photosynthetic bacteria in recent years is reviewed and combined with the latest astrobiology research, revealing the photosynthetic pigment composition of different photosynthetic bacteria. Cyanobacteria contain Chlorophyll (Chl) for the absorption and transfer of light energy including Chl a, CHl b, Chl d, carotenoids and phycobilins, of which chlorophyll b and chlorophyll d are not contained in all types of cyanobacteria, PB contain BChl a or BChl b,  GSB contains photopigments BChl a, Chl a, and BChl c, d, or e, GNSB contains photopigments BChl a and/or BChl c, and AAPB mainly contain BChl a. Understanding how Photosynthesis evolves, what kinds of photosynthetic pigments and how do it function could provide a new insight into the origins of life and are beneficial to detection of extraterrestrial life and potential habitable planets.