Phycobilins

Rakhimberdieva, M. G., D. V. Vavilin, W. F. Vermaas, I. V. Elanskaya, and N. V. Karapetyan (2007b). Phycobilin/ chlorophyll excitation equilibration upon carotenoid-induced non-photochemical fluorescence quenching in phycobilisomes of the cyanobacterium Synechocystis sp. PCC 6803. Biochim Biophys Acta 1767(6) 757-765. 

Rudiger, W. Photochemistry of phycobilins. In Biophysics of Photoreceptors and Photobehaviour of Microorganisms (Colombetti, G., ed.). Pisa Litofelici 1975, pp. 184-197... 

Pigments of the photosynthetic apparatus can also be destroyed after UV-exposure, with the phycobilins (main pigments of red algae and cyanobacteria) being the most sensitive, and carotenoids generally being less affected than chlorophylls (Teramura 1983). 

Fig. 8.3 Top. Pigments in Monascus. Middle. Phycobilins in algae. Bottom. Pigments in...

The future of the phycobilins looks promising for two reasons. First, there are no other blue natural colorants available and, admittedly, blue is not a favorite food... 

Cyanobacteria and red algae employ phycobilins such as phycoerythrobilin and phycocyanobilin (Fig. 19-40b) as their light-harvesting pigments. These open-chain tetrapyrroles have the extended polyene system found in chlorophylls, but not their cyclic structure or... 

FIGURE 19-43 A phycobilisome. In these highly structured assemblies found in cyanobacteria and red algae, phycobilin pigments bound to specific proteins form complexes called phycoerythrin (PE), phycocyanin (PC), and allophycocyanin (AP). The energy of photons absorbed by PE or PC is conveyed through AP (a phycocyanobilin-binding protein) to chlorophyll a of the reaction center by exciton transfer, a process discussed in the text. 

While the following discussion centres on the Mg2+-containing pigments, it should be noted that there are two additional major categories of non-chlorophyll-type pigments — the carotenoids and the phycobilins. The latter compounds are open-chain tetrapyrroles. 

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