Plastid membranes from seedlings that have been cultivated in
the dark after several hours of light exposure: (a) xantha-
a63: The uncontrolled synthesis of lipids specific for chloroplasts
leads to the formation of membranes arranged like honeycombs together
with prolamellar bodies and grana.
und Grana.
(b) xantha-d3l: Thylacoids aggregate as giant grana.
(c) xantha-f60: Mutants with an inhibited chlorophyll synthesis.
The synthesis is blocked between protoporphyrin IX and Mg-protoporphyrin.
As a consequence is the mutant unable to arrange its thylacoids
as grana.
(d) tigrina-o34: The mutant has a defect in the regulation
of chlorophyll and carotene synthesis. The accumulation of a higher
saturated carotene, the lycopine, in the plastids of the mutant
causes the formation of abnormally structured grana. e. xantha-b18:
Mutants with a spheroid granum (K. W. HENNINGSEN, J. E. BOYNTON,
O. F. NIELSEN and D. von WETTSTEIN, 1985).
© Peter v. Sengbusch - b-online@botanik.uni-hamburg.de