Transformation of Protochlorophyllide, Formed from Exogenous δ-Aminolevulinic Acid, in Continuous Light and in Flashlight.

δ-Aminolevulinic acid supplied to dark grown isolated leaves of wheat causes an accumulation of protochlorophyllide which is only partly transformed to chlorophyllide α in continuous light. At the same time a considerable photodestruction of both pigments takes place. By a suitable combination of short light flashes and dark periods it is possible, however, to obtain at least double the amount of the protochlorophyllide transformed without photodestruction. The transformation is shown to be dependent on the dark interval between the light flashes. Possible connections with the formation of the protein part of the protochlorophyllide holochrome are discussed. [ABSTRACT FROM AUTHOR]