Bacteria, photosynthetic

Methanogenic bacteria Photosynthetic bacteria Methanogenic and acetogenic bacteria Streptomyces sp. 

Sulfur-oxidizing bacteria Photosynthetic sulfur bacteria  

Chlorosomes see Photosynthetic bacteria, Photosynthetic pigment systems. 

The function of ferredoxin in anaerobic bacteria, photosynthetic bacteria, and green plants is described in the remainder of this chapter. Some of the characteristics of these organisms are illustrated in Fig. 9. Anaerobic bacteria, such as C. pasteurianum, obtain their energy chemically by fermenting carbon compounds. In fermentation, the oxidation of a substrate is coupled to the production of ATP and a reductant, which are both necessary for the synthesis of new cell material. The carbon required for biosynthesis comes from fermentation intermediates and CO2. 

Fig. 9. Some characteristics of anaerobic bacteria, photosynthetic bacteria, and green plants.

As indicated above, the crystallographic studies on purple bacteria photosynthetic RC, Rps. viridis, and Rb. sphaeroides revealed the configuration of chromophores in RC in detail (Figure 2). 2 According to these studies, chromophores in RC display an approximate twofold symmetry of two proteins designated as L and M subunits with the 

Chlorophylls a and b contain the alcohol phytol bacteriochlorophylls a and b have either phytol or geranylger-aniol, depending on the species of bacteria. Photosynthetic organisms also contain small amounts of pheophytins or bacteriopheophytins, which are the same as the corresponding chlorophylls or bacteriochlorophylls except that two hydrogens replace the Mg2+ (see fig. 15.4). We will see that 

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