Chlorophyll Formation in the YG-6 Mutant ofChlorella regularis: Accumulation of Protochlorophyllide and Protochlorophyll Esterified with Geranylgeraniol

摘要

A chlorophyll-less mutant, YG-6, was produced by UV treatment of the wild strain ofChlorella regularis(S-50). Cells grown for 3 days in darkness showed a red absorption maximum at 634 nm and a shoulder near 650 nm, indicative of the accumulation of at least two spectral forms of protochlorophyll(ide). Protochlorophyllide (Pchlide), and one species only of Pchlide ester, protochlorophyll esterified with geranylgeraniol (Pchl GG) were separated, the latter with absorption maxima in diethyl ether at 438, 574 and 624 nm.Spectroscopically, Pchl GG was identical with divinyl-protochlorophyll. The content of Pchlide was 10 to 13 times that of Pchl GG. Both paper and high-performance liquid chromatography showed the phototransformation of Pchlide, but no Pchl GG was present. This suggests that Pchl GG is not a direct precursor of chlorophyllaesterified with geranylgeraniol.