3种食用菌漆酶活性比较及其基因的克隆与序列分析

[目的]研究食用菌漆酶基因的差异以及漆酶的活性。[方法]利用编码杏鲍菇漆酶基因序列（GenbankNo．AY686700）设计特异性引物，采用PCR方法获得3种典型木腐食用菌（杏鲍菇、平菇、白灵菇）漆酶的基因序列。[结果]扩增得到的片段长度均为2606bp，通过对基因序列的内含子／外显子分析，获得漆酶编码区的cDNA，该基因的开放阅读框由1596个核苷酸组成，编码一个由531个氨基酸组成的多肽。3种食用茵漆酶基因的核苷酸序列、氨基酸序列同源性均为99．81％，说明漆酶的一级结构序列具有很高的保守性。[结论]序列的差异性、氨基酸跨膜区的不同及蛋白质的构象不同可能导致漆酶活性的高低。

Cloning and Sequence Analysis of the Laccase Gene and Comparison of Laccase Activity from Three Kinds of Edible Fungi

[ Objective ] To study the differences of edible fungi laccase gene and activity of laccase. [ Method ] According to the laccase gene of￥ Pleurotus eryngii ￥ （ Genebank No. AY686700）, specific primers were designed, three kinds of edible fungi laccase gene were obtained by using PCR. [ Result] The length of amplification fragment was 2 606 bp, through the intron and exon analysis of gene sequence, coding cDNA of laccase was obtained. It contains one open reading frame（ ORF）, which encodes for a polypeptide containing 531 amino acids. The nucleic acid homology of three edible fungi laccase genes and amino acids homology were both 99.81%. [ Conclusion] The sequence differ- ences, amino acid transmembrane area differences and the difference of protein conformation may cause the laccase activity of high and low.