Modulation of PSI and PSII Organization During Loss and Repair of Photosynthetic Activity in a Temperature Sensitive Mutant of Chlorella pyrenoidosa

Photosynthetic activity and organization of chlorophyll(Chl)-protein complexes in a temperature sensitive mutant of Chlorella pyrenoidosa have been investigated. The mutant is practically indistinguishable from wild type cells when grown at 25 C. However, mutant cells grown at 33 C do not synthesize Chl and lose their ability to evolve O₂. O₂ evolution and Chl synthesis are restored upon incubation of the 33 C grown cells at 25 C in absence of cell division (repair).