How carotenoids protect bacterial photosynthesis

The essential function of carotenoids in photosynthesis is to act as photop rotective agents, preventing chlorophylls and bacteriochlorophylls from sen sitizing harmful photodestructive reactions in the presence of oxygen. Base d upon recent structural studies on reaction centres and antenna complexes from purple photosynthetic bacteria, the detailed organization of the carot enoids is described. Then with specific reference to bacterial antenna comp lexes the details of the photoprotective role, triplet-triplet energy trans fer, are presented.