Environmental Engineering Laboratory, Department of Civil Engineering, University of Sherbrooke, 2500 Boulevard de l'Université, Sherbrooke, Quebec, Canada J1K 2R1.
Bioresour Technol. 2013 Jan;128:640-5. doi: 10.1016/j.biortech.2012.10.058. Epub 2012 Nov 2.
Laccase and laccase-based cross-linked enzyme aggregates (CLEAs) were stabilized through the formation of a surrounding polymeric network made of chitosan and 3-aminopropyltriethoxysilane. The thermoresistance of the resulting enzyme polymer engineered structures of laccase (EPES-lac) and CLEAs (EPES-CLEA) were more than 30 times higher than that of free laccase and CLEAs at pH 3 and 40 °C. The EPES showed higher residual activity than the unmodified biocatalysts against chaotropic salts (up to 10 times), EDTA (up to 5 times), methanol (up to 15 times) and acetone (up to 20 times). The Michaelis-Menten kinetic parameters revealed that the affinity for 2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulphonic acid) has doubled for the EPES-lac and EPES CLEA compared to their unmodified forms. The EPES-lac structures acted optimally at pH 4 and their activity was nearly temperature-independent, while the laccase activity of EPES-CLEA was optimal at pH 4 and 60 °C. Globally, the EPES have shown significantly improved properties which make them attractive candidate for the development of laccase-based applications.
漆酶和基于漆酶的交联酶聚集体（CLEAs）通过形成由壳聚糖和 3-氨丙基三乙氧基硅烷组成的周围聚合网络而稳定。所得漆酶的酶聚合物工程结构（EPES-lac）和 CLEAs（EPES-CLEA）的热稳定性比游离漆酶和 CLEAs 在 pH 3 和 40°C 时高出 30 多倍。与未修饰的生物催化剂相比，EPES 对离液盐（高达 10 倍）、EDTA（高达 5 倍）、甲醇（高达 15 倍）和丙酮（高达 20 倍）具有更高的残留活性。米氏动力学参数表明，与未修饰形式相比，EPES-lac 和 EPES-CLEA 对 2,2'-联氮双（3-乙基苯并噻唑啉-6-磺酸）的亲和力增加了一倍。EPES-lac 结构在 pH 4 下最佳发挥作用，其活性几乎与温度无关，而 EPES-CLEA 的漆酶活性在 pH 4 和 60°C 下最佳。总体而言，EPES 表现出显著改善的性能，使其成为基于漆酶的应用开发的有吸引力的候选物。
