Magnesium protoporphyrin monoester and protoporphyrin monomethyl ester in chlorophyll biosynthesis.

In previous studies on Chlorella mutants, several compounds were isolated which were postulated to be intermediates in chlorophyll synthesis. Protoporphyrin-9 was identified as the main porphyrin product from one mutant (I), magnesium protoporphyrin was found in another mutant (a), and magnesium vinylpheoporphyrin a5 in a third (3). Here we report on the isolation and identification of magnesium protoporphyrin monoester and of protoporphyrin monomethyl ester from mutant No. 60-A. We have also isolated magnesium protoporphyrin monoester from barley seedlings treated with d-aminolevulinic acid, the details of which will be described in another paper.