Phycoerythrin

<p>Phycoerythrin (PE) is a red protein-<a href="/facts/Pigment/I3clCYkF">pigment</a> complex from the light-harvesting <a href="/facts/Phycobiliprotein/DPw6N454">phycobiliprotein</a> family, present in <a href="/facts/Cyanobacteria/S8bKxIU9">cyanobacteria</a>, <a href="/facts/Red_algae/jCeIc7Kq">red algae</a> and <a href="/facts/Cryptomonad/4r1SHPtg">cryptophytes</a>, accessory to the main <a href="/facts/Chlorophyll/1Sb0NyyM">chlorophyll</a> pigments responsible for <a href="/facts/Photosynthesis/TMV7w693">photosynthesis</a>.The red pigment is due to the prosthetic group, phycoerythrobilin, which gives phycoerythrin its red color.
</p><p>Like all phycobiliproteins, it is composed of a protein part covalently binding <a href="/facts/Chromophore/9RykVkek">chromophores</a> called <a href="/facts/Phycobilin/YD9TdjoB">phycobilins</a>. In the phycoerythrin family, the most known phycobilins are: <a href="/facts/Phycoerythrobilin/X2HJMcNG">phycoerythrobilin</a>, the typical phycoerythrin acceptor chromophore. Phycoerythrobilin is a linear tetrapyrrole molecule found in cyanobacteria, red algae, and cryptomonads. Together with other bilins such as phycocyanobilin it serves as a light-harvesting pigment in the photosynthetic light-harvesting structures of cyanobacteria called phycobilisomes. Phycoerythrins are composed of (αβ) monomers, usually organised in a disk-shaped <a href="/facts/Protein_quaternary_structure/ukuyKJfj">trimer</a> (αβ)3 or <a href="/facts/Protein_quaternary_structure/ukuyKJfj">hexamer</a> (αβ)6 (second one is the functional unit of the <a href="/facts/Phycobilisomes/Ur1Cbbh7">antenna rods</a>). These typical complexes also contain a third type of subunit, the γ chain.
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Phycoerythrin open-in-new

Phycoerythrin