Green filamentous bacteria chlorosome

The green filamentous bacteria were discovered in the early seventies (2). Only one species has been extensively studied so far, Chloroflexus aurantiacus, a thermophilic bacterium living in hot springs in various parts of the world. The main pigment of Cfl. aurantiacus is BChl c, contained in chlorosomes, whereas the cytoplasmic membrane contains BChl a. Chloroflexus can grow phototrophically as well as heterotrophically in the presence of oxygen. 

The absorption spectra of green sulfur as well as of green filamentous bacteria are dominated by strong absorption bands near 460 and 720-760 nm. These bands belong to BChl c, d ox e in the chlorosomes, the major antenna systems in these bacteria. In addition to BChl c chlorosomes of green sulfur bacteria (5-7) as well as those of Cfl. aurantiacus (5,8) contain small amounts... 

Fig. 4. Structural model for the chlorosome-reaction center complex of filamentous green bacteria. BChl molecules In chlorosome and cytoplasmic membranes are represented by squares. Direction of the transition dipole moment of the lowest excited singlet state of the respective pigment complex or molecules is represented by a straight arrow. Curved arrows show direction of energy transfer. See text for other details. Figure source same as Figure 2 in this chapter.

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