Lipid and pigment composition of a chlorophyll<i>b</i>‐deficient mutant of<i>Chlamydomonas reinhardii</i>

Abstract

Lipids and pigments of the chlorophyll b ‐deficient mutant pg‐113 and the parent strain (ps) of Chlamydomonas were analysed and compared. Monogalactosyldiglyceride, digalactosyldiglyceride, diacylglyceryl(N, N, N‐trimethyl)homoserine, sulfoquinovosyldiglyceride, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol were found as major lipid components. While the lipid patterns were qualitatively and quantitatively almost the same in the two strains, the C 16 /C 18 fatty acid ratios were different, 0.85 in the mutant and 1.11 in the parent strain. Furthermore, the relative amounts of C 16 ‐ and C 18 ‐monoene fatty acids were slightly enhanced and the C 18 ‐trienes slightly reduced in the mutant. In the parent strain, chlorophylls a and b , α‐ and β‐carotene, lutein, violaxanthin, neoxanthin and loroxanthin were detected by HPLC. In the mutant, similar pigments were found, except that only traces of chlorophyll b and a reduced amount of neoxanthin were present. Since no chlorophyll‐protein complex CP II could be detected in the mutant by electrophoresis, the possible interrelationships between pigment deficiency and alteration of chlorophyllprotein complexes are discussed.