Figure 5.

Analysis of ALA-synthesizing capacity (top) and ALA- dehydratase activity (bottom) of control plants and selected transgenic plants expressing Chl H antisense RNA. Top panel, Leaf discs of the fourth leaf were incubated in the light for 6 h in levulinic acid, an inhibitor of ALA-dehydratase. Amounts of accumulated ALA were determined spectrophotometrically after reaction with Ehrlichs reagent. Values represent means ± sd from three separate experiments. Bottom panel, ALA-dehydratase activity was measured from total extracts of the fourth leaf. Values represent means ± sd from three separate preparations.