Effetto di Inibitori Della Sintesi Proteica Sull'aumento di Attività Enzimatiche e sul Risveglio del Metabolismo Nell'Endosperma di Semi di Ricino in Germinazione

Abstract

Abstract Effects of inhibitors of protein synthesis on the development of metabolic activity in the endosperm during the germination of castor bean seeds. — The effect of chloramphenicol, streptomycin and actinomycin-C on the increase of the activities of glyceroaldehyde-phosphate dehydrogenase, aldolase, glucose-6-phosphate dehydrogenase, fructose 1–6 diphosphate-1-phosphatase, phosphomonoesterase, in the endosperm of germinating castor bean seeds was investigated. In all cases, the protein synthesis inhibitors depressed the activation of the enzymes tested: in particular, actinomycin (50 μg/ml) completely suppressed the increase of the activities. The development of the rate of oxygen uptake and the conversion of fats to sugars was strongly affected by the inhibitors. These data suggest that the increase of the activities of several enzymes in the germinating endosperm is dependent on enzyme synthesis rather than on the conversion from the inactive to the active form of the enzymes.