摘要
The tobacco RuBPcase was purified by the method of (NH 4) 2SO 4 precipitation and Sephadex G 200 column chromatography. The effects of Ln 3+ on inhibition of RuBPcase activity were studied. The results show that the v max (maximum velocity) of RuBPcase does not change, but its k m (Michaelis constant) increases with a k i (inhibitor constant) when increasing the concentration of Ln 3+ in enzymatic reaction. It indicates that the inhibitory action of Ln 3+ on tobacco RuBPcase is a model of competitive inhibition with Mg 2+ . The k i of La 3+ , Ce 3+ and Gd 3+ is 26 3, 34 3 and 200 μmol·L -1 , respectively. Their inhibitory action on the RuBPcase is in the order of La 3+ >Ce 3+ Gd 3+ .
The tobacco RuBPcase was purified by the method of (NH 4) 2SO 4 precipitation and Sephadex G 200 column chromatography. The effects of Ln 3+ on inhibition of RuBPcase activity were studied. The results show that the v max (maximum velocity) of RuBPcase does not change, but its k m (Michaelis constant) increases with a k i (inhibitor constant) when increasing the concentration of Ln 3+ in enzymatic reaction. It indicates that the inhibitory action of Ln 3+ on tobacco RuBPcase is a model of competitive inhibition with Mg 2+ . The k i of La 3+ , Ce 3+ and Gd 3+ is 26 3, 34 3 and 200 μmol·L -1 , respectively. Their inhibitory action on the RuBPcase is in the order of La 3+ >Ce 3+ Gd 3+ .
基金
theNationalNaturalScienceFoundationofChina ( 2 980 5 0 0 3)
