Polypeptides of the Light-Harvesting Complex in A Chlorophyll b-Less Mutant of Chlamydomonas Reinhardii

Abstract

The studies on chlorophyll b-deficient mutants of higher plants or green algae were of great help in the identification of the chlorophyll-protein complex II (CP II) as the light-harvesting chlorophyll a/b-protein complex (LHCP) (Thornber, Highkin, 1974). This complex is not involved in any direct photosynthetic reaction. However, it has been found that it is involved in the stacking of thylakoids and in the energy distribution between photosystem I and II (Burke et al., 1979). This energy distribution is regulated by phosphorylation of the LHC-apoproteins (Bennett et al., 1980). The chlorophyll b-less barley mutant chlorina f2 has been studied very thoroughly. In this mutant, which completely lacks in chlorophyll b and in CP II, the thylakoids are still extensively stacked (Miller et al., 1976), but energy distribution is reduced (Haworth et al., 1982), indicating that the LHCP is predominantly involved in the regulatory function of energy distribution and less so in the formation of membrane stacks. However, in this mutant two of the three LHC-apoproteins are also missing (Bellemare et al., 1982).