Vv. Rassadina et al., FORMATION OF MONOVINYL AND DIVINYL DERIVATIVES OF MAGMESIUM-PROTOPORPHYRIN-IX MONOMETHYL ESTER AND PROTOCHLOROPHYLLIDE IN MONOCOTS, Soviet plant physiology, 39(5), 1992, pp. 590-593
We studied the chemical heterogeneity of Mg-protoporphyrin IX monometh
yl ester and protochlorophyllide (PC) in etiolated, greening, and gree
n plants under normal conditions and after their treatment with 5-amin
olevulinic acid (ALA) or ALA in combination with the chelator of metal
s 2,2'- dipyridyl. In contrast to dicots, the studied monocots (cereal
s in particular) show only monovinyl (MV) PC under conditions of etiol
ation or during shading of greening and green plants. Under conditions
of shading, divinyl (DV) PC appears only in plants supplied with exog
enous ALA, in the presence of which an increase occurs in the number o
f functioning chlorophyll biosynthesis centers (CBC) transforming ALA
into PC. The behavior of DV-PC corresponds to that of an intermediate,
namely the natural precursor of MV-PC in biosynthesis. Activating the
link of exogenous ALA synthesis, light actuates all CBC, and formatio
n of DV-PC begins to be clearly registered also.