Cyanobacteria and higher plantscontain -carotene as a primary carotenoid found in both PSI and PSII (Fig. 3). In the case of A. marina, -carotene was detected instead of -carotene, and zeaxanthin, an oxidative product of -carotene, was identified as a major carotenoid (4, 13). A similar carotenoid composition has been reported only in Prochlorococcus species that contain atypical, divinyl-Chls, an