[Isolation and properties of the pigment-protein complex (protochlorophyllide - holochrome) from etiolated leaves of corn sprouts].

A pigment -- protein complex was isolated from etiolated leaves of corn sprouts using treatment by the detergent Triton X-100, ultracentrifugation and gel-filtration. The complex has a molecular weight of 50000 and upon illumination can convert protochlorophyllide (Pchld) into chlorophyllide (Chld). The low temperature fluorescence spectra of dark preparations reveal maxima of Pchld 632 (photo-inactive form) and Pchld 653 (photo-active form). Upon illumination Pchld 653 is converted into Chld 685. The kinetics of the precursor photoconversion into Chld are coincident with those for photoconversion in native etiolated corn leaves. The complex is completely inactivated at a decrease of pH down to 6.5 or during incubation at high temperature (30 degrees).