| Abstract: | The presence of translational inhibitory activity in partially purified extracts from several paleoendemisms from Spain was investigated. The precipitates from 40-80% (NH4)2SO4 fraction from Petrocoptis glaucifolia and Petrocoptis grandiflora displayed a strong inhibitory activity on the protein synthesis of cell-free extracts from rat liver, rabbit reticulocytes and yeast and to a much lower extent on the protein synthesis in isolated rat liver cells. The inhibitors seem to be proteins since they were precipitated by high salt concentrations, were non-dialysable and were inactivated by heat. Since the partially purified extracts did not show unspecific RNA-A or protease activities, the active compounds can be considered to belong to the plant ribosome-inactivating proteins. |
