Isolation of oxygen‐evolving phycobilisome—photosystem II particles from Porphyridium cruentum

Abstract
Photosystem II phycobilisome particles were isolated from the red alga Porphyridium cruentum in a sucrose—phosphate—citrate—magnesium medium. These particles showed high rates of oxygen evolution in the water‐to‐silicomolybdate reaction (2300 μmol O2.mg chl‐1.h‐1). Photosystem I, according to fluorescence emission spectra (−196°C), was greatly reduced or absent. The results demonstrate a close physical relationship of photosystem II with the phycobilisomes which are the major light harvesting antennae in this organism.