GENETIC-CONTROL OF THE BIOSYNTHESIS OF CH LOROPLAST PIGMENTS IN GREEN-ALGAE

Pigmentation traits in Chlamydomonas are known to be controlled cooper atively by nuclear and chloroplast genes. A method for obtaining mutan ts without chlorophyll b was developed, which offers a possibility for genetic analysis of chlorophyll b synthesis. Meiotic analysis of muta nts selected for increased protoporphyrin IX content revealed a mutant chlorplast gene allele that affects the activity of aminolevulinate-s ynthesizing enzymes. Polyploids of Chlamydomonas reinhardtii, first is olated by us, were used for genetic analysis of pigment mutations. The discovery of phytoene in green photosensitive mutants of Chlamydomona s allowed investigations of the genetic control of phytoene desaturase (a key enzyme in carotenoid biosynthesis). Future studies on the mole cular and genetic nature of the above mutations are outlined.