Effect of sodium dodecylsulfate on the degradation of ribulose-1,5-bisphosphate carboxylase/oxygenase in the extract of rice (Oryza sativaL.) leaves

Abstract

Abstract Degradation of ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO) was examined in the soluble extract of rice (Oryza sativa L.) leaves in the presence of SDS. The extracts were incubated in the presence of 300 mM of 2-mercaptoethanol, 10% (w/v) of glycerol and SDS at various concentrations, in the pH range of 5.5 to 8.5, at 30°C. Degradation of RuBisCO was detected as a decrease of the large subunit of RuBisCO by SDS-polyacrylamide gel electrophoresis followed by staining with Coomassie Blue R-250. Degradation of RuBisCO was particularly pronounced when the reaction mixtures contained SDS and was strongly dependent on the concentration of SDS in the reaction mixture. The degradation at pH 5.5 was mostly accelerated in the concentration range of 0.2-0.5% (w/v) of SDS. The lower the pH of the reaction mixture was adjusted, the faster RuBisCO was degraded. The degradation was clearly inhibited by leupeptin or monoiodeacetic acid.