Abstract
While cyanobacteria have peptidoglycan layer between inner and outer membranes and 10 genes for its synthesis, this wall structure has not be observed yet in plastids of green plants. We found 8 homologous genes for the peptidoglycan synthesis pathway in moss Physcomitrella patens. Furthermore, Arabidopsis genome harbored 4 genes, in which two genes were impossible to find in the EST library of P. patens. Almost of all genes were predicted to be targeted into chloroplasts. The disruptants of the MurE genes in both of P. patens and A. thaliana showed indeed different phenotypes on plastids. In Physcomitrella, enormous and minimum chloroplasts with decreased number in comparison with those of wild-type plants were observed in the protonema and leafy cells. Leaves of the Arabidopsis murE disruptants appeared to be pale yellow. Electron microscopic analysis displayed that development from proplastid to chloroplasts seemed to be incompletely in the disruptants.
