Chlorosome
As chlorosomes ( from Ancient Greek χλωρός, chloros - bright green, fresh and σῶμα soma - body ) are intracellular organelles called photosynthesis electrifiable Green sulfur bacteria and green non- sulfur bacteria ( Chloroflexi ). Chlorosomes are rectangular to ellipsoidal structures having a length of 100 to 200 nm, 50 to 100 nm in width and 15 to 30 nm in height. They mainly contain bacteriochlorophylls (c, d or e) and lower amounts carotenoids and quinones and are of a non- unit membrane ( a galacto- lipid layer with different proteins ) surrounded. Functional form Chlorosomes a photosynthetic antenna complex, which is used for absorbing light. The chlorosomes are connected by FMO - proteins with the reaction centers in the cell membrane. Here, the conversion of the absorbed light energy takes place (ATP) into chemical energy. Compared with similar structures of other phototrophic organisms chlorosomes are relatively large and are characterized by the absence of a protein matrix that supports the arrangement of photsynthetischen pigments. Current models that describe the organization of bacteriochlorophyll and carotenoids in chlorosomes, assume a layered arrangement of the pigments in the interact farnesol - tails of bacteriochlorophyll with each other and with the carotenoids. In this way, a structure that corresponds to a lipid multilayer.
Examples of bacteria containing chlorosomes:
- Chlorobiaceae Chlorobium tepidum
- Chlorobium phaeobacteroides
- Chlorobium phaeovibrioides
- Chlorobium vibrioforme
- Chlorobium limicola
- Pelodictyon lutoleum
- Prostecochloris aestuarii
- Chloroflexi Chloroflexus aurantiacus
- Chloroflexus aggregans
- Oscillochloridaceae Oscillochloris trichoides
- Chloronema giganteum
The light absorption with the aid of Chlorosomes is very effective. Therefore, Green sulfur bacteria are also with little light and can still live in water depths that are no longer suitable for many other phototrophic organisms.
- Bacteriology