Studies on the regeneration of protochlorophyllide after brief illumination of etiolated bean leaves.

The effects of various inhibitors of nucleic acid and protein synthesis on protochlorophyllide synthesis in dark-grown Phaseolus vulgaris var. Red Kidney have been studied. Actinomycin D, chloramphenicol, and puromycin inhibit the regeneration of protochlorophyllide holochrome (detected as a 650 mmu absorption peak) in vivo in darkness after photoconversion of endogenous protochlorophyllide a to chlorophyllide a; this inhibition does not occur in similarly treated leaves supplied with delta-aminolevulinic acid.These data suggest that the regeneration of protochlorophyllide results from the synthesis of RNA and enzymes required for the production of delta-aminolevulinate.