A Comparative Study of Quantitative Relationship between Phycobiliproteins and Photosystem II in Cyanobacteria and Red Algae

Quantitative relationship between phycobiliprotein (PBP) andPS II contents was compared for 10 cyanobacterial and 3 redalgal strains. Following results were obtained: (1) contentof PBP per PS II was always equal to that of one phycobilisome(PBS) when PBS was hemidiscoidal type, (2) unusually high ratiosbetween antenna PBP [phycoerythrin (PE) and phycocyanin (PC)]and allophycocyanin contents were found in the PE-containingcyanobacteria Phormidium persicinum, Phormidium sp. NIBB 1052and Synechococcus sp. NIBB 1059 and the red alga Porphyra yezoensissuggesting that PBS in these organisms is not ordinary hemidiscoidaltype, and (3) the PBP content per PS II in Synechococcus NIBB1059 and P. yezoensis was as small as 14 to 13 of that of onePBS similarly to the case of Porphyridium cruentum. Resultssuggest that (1) hemidiscoidal PBS is the antenna for only onePS II, but (2) in some of organisms containing non-hemidiscoidalPBS, one PBS becomes a common antenna for plural PS II (around4), and (3) such PBS occurs not only in red algae but also incyanobacteria. ¹ Present address: Department of Biology, Faculty of Science,Toho University, Funabashi, Chiba 274, Japan. 1219 (Received April 15, 1987; Accepted July 11, 1987)