Microperoxidase 11(MP 11) was immobilized on the surface of a silanized glass carbon electrode by means of the covalent bond with glutaraldehyde. The measurements of cyclic voltammetry demonstrated that the formal r...Microperoxidase 11(MP 11) was immobilized on the surface of a silanized glass carbon electrode by means of the covalent bond with glutaraldehyde. The measurements of cyclic voltammetry demonstrated that the formal redox potential of immobilized MP 11 was -170 mV, which is significantly more positive than that of MP 11 in a solution or immobilized on the surface of electrodes prepared with other methods. This MP 11 modified electrode showed a good electrocatalytic activity and stability for the reduction of oxygen and hydrogen peroxide.展开更多
Interaction between rare earth ion praseodymium (Pr(Ⅲ)) and MP11 with/without hydrogen ion (H +) in different media( aqueous, phosphate buffer, physiological condition) were studied by UV Vis spectroscopy. All the ...Interaction between rare earth ion praseodymium (Pr(Ⅲ)) and MP11 with/without hydrogen ion (H +) in different media( aqueous, phosphate buffer, physiological condition) were studied by UV Vis spectroscopy. All the results indicate that Pr(Ⅲ) interacts with MP11, increasing the non planarity of porphyrin periphery, leading MP11 to form two conformations when titrated by Pr(Ⅲ). Excessive Pr(Ⅲ) acts as a contaminant in living organism. H + and Pr(Ⅲ) have antagonistic effect on MP11, suggesting that at suitable concentration under physiological conditions, Pr(Ⅲ) can be used as biomodulator in protecting plants from acid rain stress or in rehabilitating the harm.展开更多
The interaction between Sm3+and MP 11 in the aqueous solution was investigated with cyclic voltammetry, UV Vis absorption spectrum and circular dichroism. It was found for the first time that Sm3+could bond to O of ca...The interaction between Sm3+and MP 11 in the aqueous solution was investigated with cyclic voltammetry, UV Vis absorption spectrum and circular dichroism. It was found for the first time that Sm3+could bond to O of carboxyl group in the heme group altering the surface charge of MP 11 molecule and thus increasing its diffusion coefficient.In addition, the interaction between Sm3+and MP 11 molecule would change the secondary structure of the MP 11 molecule increasing the exposure extent of the heme group in the MP 11 molecule.The above results could increase the reversibility of the electrochemical reaction of MP 11.展开更多
It was found that microperoxidase-11 (MP-if) can undergo photoreduction at the bareroughened silver electrode. No photoreduction happens at the roughened silver electrodemodified with mercaptoundecanoic carboxylic aci...It was found that microperoxidase-11 (MP-if) can undergo photoreduction at the bareroughened silver electrode. No photoreduction happens at the roughened silver electrodemodified with mercaptoundecanoic carboxylic acid/poly-lysine. The photoreduction mechanismis discussed.展开更多
基金Supported by"973" Project(No. G2 0 0 0 0 2 6 4 0 8) the National Natural Science Foundation of China(No.2 99730 15 ) the Natural Science Foundation of Heilongjiang Province(B2 0 0 0 - 0 6 ) and the Natural Science Foundation of Eduction Comm it-
文摘Microperoxidase 11(MP 11) was immobilized on the surface of a silanized glass carbon electrode by means of the covalent bond with glutaraldehyde. The measurements of cyclic voltammetry demonstrated that the formal redox potential of immobilized MP 11 was -170 mV, which is significantly more positive than that of MP 11 in a solution or immobilized on the surface of electrodes prepared with other methods. This MP 11 modified electrode showed a good electrocatalytic activity and stability for the reduction of oxygen and hydrogen peroxide.
文摘Interaction between rare earth ion praseodymium (Pr(Ⅲ)) and MP11 with/without hydrogen ion (H +) in different media( aqueous, phosphate buffer, physiological condition) were studied by UV Vis spectroscopy. All the results indicate that Pr(Ⅲ) interacts with MP11, increasing the non planarity of porphyrin periphery, leading MP11 to form two conformations when titrated by Pr(Ⅲ). Excessive Pr(Ⅲ) acts as a contaminant in living organism. H + and Pr(Ⅲ) have antagonistic effect on MP11, suggesting that at suitable concentration under physiological conditions, Pr(Ⅲ) can be used as biomodulator in protecting plants from acid rain stress or in rehabilitating the harm.
文摘The interaction between Sm3+and MP 11 in the aqueous solution was investigated with cyclic voltammetry, UV Vis absorption spectrum and circular dichroism. It was found for the first time that Sm3+could bond to O of carboxyl group in the heme group altering the surface charge of MP 11 molecule and thus increasing its diffusion coefficient.In addition, the interaction between Sm3+and MP 11 molecule would change the secondary structure of the MP 11 molecule increasing the exposure extent of the heme group in the MP 11 molecule.The above results could increase the reversibility of the electrochemical reaction of MP 11.
基金the National Natural Science Foundation of China(No.20673136,20706056)the National"863"High-Technology Research Program of China(2006AA05Z136,2007AA05Z141)the 100 People Plan Program of the Chinese Academy of Sciences and the Pujiang Program of Shanghai City(No.06PJ14110) for support of this work
文摘It was found that microperoxidase-11 (MP-if) can undergo photoreduction at the bareroughened silver electrode. No photoreduction happens at the roughened silver electrodemodified with mercaptoundecanoic carboxylic acid/poly-lysine. The photoreduction mechanismis discussed.
