Phycobilisomes (PBSs) are the major light-harvesting systems in cyanobacteria and red algae. PBS is a supercomplex that is composed of a core complex and multiple peripheral rod complexes. Typically, the core consists of two or five cylinders lying on the membrane with, in most cases, multiple rods radiating from the core to form a hemidiscoidal structure. The building units of the core cylinders and the peripheral rods are trimeric and hexameric discs, in which a monomer consists of a pair of related phycobiliproteins (PBPs), such as phycorerythrins, phycoerythrocyanins, phycocyanins, and allophycocyanins. The discs are connected to each other via specific linker polypeptides to form peripheral rods or core cylinders. Linker polypeptides share a conserved domain of ~180 residues, which can be present in one or multiple copies PMID:2107546,PMID:1743523,PMID:15922288,PMID:17310305,PMID:17468217.

INTERPRO:IPR001297