Phycoerythrin

Phycoerythrin is a red protein from the light-harvesting phycobiliproteins family, isolated from red, blue-green, and crytomonad algae. A strong absorption peak exists at about 566nm, and a strong emission peak exists at 575nm +/-10 nm. (Phycoerythrin absorbs blue light and reflect red light.) In algae, phycoerythrin is an accessory pigment to the main light-absorbing chlorophyll pigments responsible for photosynthesis. R-Phycoerythrin is useful in the laboratory as a fluorescence-based indicator for the presence of cyanobacteria and for labeling antibodies, among other applications.