漆酶的分子生物学研究及其应用

白腐菌所分泌的木质素降解酶主要有3种：木质素过氧化物酶、锰依赖过氧化物酶和漆酶．漆酶是近年来研究较多的一种含铜的多酚氧化酶，在白腐菌中普遍存在，也存在于少数低等真菌和植物中．漆酶多为酸性蛋白，含4个铜离子，形成3个活性区域；表面一些氨基酸被不同程度地糖基化．漆酶可催化的底物迭250种，铜离子结合区域在其催化氧化过程中起决定性作用．运用PCR技术cDNA文库技术，越来越多的漆酶基因被克隆，目前已克隆到的漆酶基因有大约20个．许多来源地基因都是以家族地形式存在于染色体上的．已研究的漆酶基因中都含有10个左右的内含子，这些内含子在活性域位置上有比较高的保守性．一些特珠序列存在与否决定了该酶的表达形式-诱导型或组合型．目前已有部分漆酶基因的异源表达获得成功．本文还介绍了漆酶在环境保护、造纸工业、食品工业等方面的应用．对近年来漆酶的研究进展进行了综述．

Molecular biology and applications of laccase

Three different enzymes are involved in lignin degradation produced by the white rot fungi, they are lignin peroxidases, manganese peroxidases and laccase. Laccase is a kind of Cu-contained polyphenol oxidizes which are being widely studied recently, it is produced by many white rot fungi and some advanced plant. Some characteristics of the laccase are also detailed. Laccase can oxidize about 250 substances, the Cu-contained areas are very important in its oxidize process. More than 20 laccase gene of different sources have been cloned in different ways, the results show that most of them were located on the chromosomes with about 10 introns. Inducible expression of laccase is determined by xeomobiotic compound binding elements existing in the upstream. Moreover, its heterogonous expressions have been reported in some systems. This review also describes laccase's application in many areas such as environment protection, immunoassay biobleaching in pulps, food industry, et al.