Phycobiliproteins are water-soluble proteins present in cyanobacteria and certain algae (rhodophytes, cryptomonads, glaucocystophytes). They capture light energy, which is then passed on to chlorophylls during photosynthesis. Phycobiliproteins are formed of a complex between proteins and covalently bound phycobilins that act as chromophores (the light-capturing part). They are most important constituents of the phycobilisomes.

Major phycobiliproteins

Characteristics

Phycobiliproteins demonstrate superior fluorescent properties compared to small organic fluorophores, especially when high sensitivity or multicolor detection required :

Applications

Phycobiliproteins allow very high detection sensitivity, and can be used in various fluorescence based techniques fluorimetric microplate assays, FISH and multicolor detection. They are under development for use in artificial photosynthesis, limited by the relatively low conversion efficiency of 4-5%.