Abstract
Chlorophyll a is synthesized from glutamic acid by many steps. Most of the genes and enzymes responsible for chlorophyll biosynthesis have been identified and well characterized. However, the gene for divinyl protochlorophyllide 8-vinyl reductase (DVP reductase), which converts divinyl protochlorophyllide a to monovinyl protochlorophyllide a, has not been identified.
In order to identify the gene for DVP reducatase, we isolated the mutant of Arabidopsis thaliana in which monovinyl chlorophylls are replaced by divinyl chlorohylls. This mutant is supposed to have a mutation in the gene for DVP reductase.
The mutants can grow photoautotrophically, but the growth rate was slow compared to wild type Columbia. The mutant has high divinyl chlorophyll a/b ratio and exhibits pale green phenotype. The PAM experiments showed that maximum photosynthetic electron transfer rates and Fv/Fm ratios were decreased in the mutant.
