Immunological identification of the polypeptide bands in the SDS‐polyacrylamide gel electrophoresis of photosystem II preparations

Antibodies raised against each of the constituent proteins of the photosystem II core complex, i.e. against the 47 kDa protein (psbB product), the 43 kDa protein (psbC product), cytochrome b‐559 (psbE and psbF products), the psbA product expressed in E. coli or against a synthetic oligopeptide corresponding to a part of the sequence of psbD gene, were utilized to determine the origin of higher molecular mass bands exhibited by SDS‐polyacrylamide gel electrophoresis of photosystem II preparations, and to identify the two medium‐size polypeptides in the 30 kDa region of the recently isolated photosystem II reaction center [(1987) Proc. Natl. Acad. Sci. USA 84, 109–112]. The result of analysis clearly indicated that the photosystem II reaction center consists entirely of D‐1 (psbA product), D‐2 (psbD product) and cytochrome b‐559.