Influence of counteranions on catalytic ability of immobilized laccase in Cu-alginate matrices: Inhibition of chloride and activation of acetate  

作　　者：Ting Pan Yao-Jin Sun Xiao-Lei Wang Ting Shi Yi-Lei Zhao 

机构地区：[1]State Key Laboratory of Microbial Metabolism,School of Life Sciences & Biotechnology,Shanghai Jiao Tong University

出　　处：《Chinese Chemical Letters》2014年第7期983-988,共6页中国化学快报（英文版）

基　　金：the National High-Tech R&D Program of China ‘‘863’’ (No.2012AA020403);the National Basic Research Program of China ‘‘973’’ (Nos.2012CB721005,2013CB966802);National Natural Science Foundation of China(Nos.21377085,21303101,31121064,J1210047);MOE New Century Excellent Talents in University(No.NCET-12-0354)

摘　　要：Laccase is a promising oxidase with environmental applications, such as lignin degradation and chlorophenol detoxification. Laccase immobilization can significantly improve physiochemical stability and reusability compared to the free enzymes. In this work, anion effect was investigated in entrapment of Cu-alginate matrix with five types of anions, including perchlorate （ClO4）, nitrate （NO3）, sulfate （SO42 ）, chloride （Cl）, and acetate （CH3CO2-）. Accordingly, chloride inhibition and acetate activation were detected in the o-tolidine kinetic experiments, while effects of the other three anions were much smaller. Such counteranion effects were also observed in the laccase-catalyzed biodegradation of 2,4- dichlorophenol. The results indicated that counteranions in the enzyme immobilization process are crucial for catalytic capacity, probably due to the competition with the carboxylate groups in alginate. Our results also imply that these anions might coordinate the copper cations in laccase.Laccase is a promising oxidase with environmental applications, such as lignin degradation and chlorophenol detoxification. Laccase immobilization can significantly improve physiochemical stability and reusability compared to the free enzymes. In this work, anion effect was investigated in entrapment of Cu-alginate matrix with five types of anions, including perchlorate （ClO4）, nitrate （NO3）, sulfate （SO42 ）, chloride （Cl）, and acetate （CH3CO2-）. Accordingly, chloride inhibition and acetate activation were detected in the o-tolidine kinetic experiments, while effects of the other three anions were much smaller. Such counteranion effects were also observed in the laccase-catalyzed biodegradation of 2,4- dichlorophenol. The results indicated that counteranions in the enzyme immobilization process are crucial for catalytic capacity, probably due to the competition with the carboxylate groups in alginate. Our results also imply that these anions might coordinate the copper cations in laccase.

关 键 词：Counterion effect Cu-alginate matrix Laccase immobilization Enzyme activity 

分 类 号：O629.8[理学—有机化学]