产木聚糖酶嗜热真菌鉴定、酶基因克隆及生物信息学分析  

Identification of Xylanase-producing Thermophilic Fungi, Cloning of Enzyme Gene and Bioinformatics Analysis

作　　者：周彩霞 赵治巧 唐宇佳 金伟琼[1] 肖义蓉 王寅生 李蕴哲 唐自钟[1] 陈惠[1] Zhou Caixia;Zhao Zhiqiao;Tang Yujia;Jin Weiqiong;Xiao Yirong;Wang Yinsheng;Li Yunzhe;Tang Zizhong;Chen Hui(College of Life Science,Sichuan Agricultural University,Ya'an,625014;Sichuan Agricultural University Hospital,Ya'an,625014)

机构地区：[1]四川农业大学生命科学学院,雅安625014 [2]四川农业大学校医院,雅安625014

出　　处：《基因组学与应用生物学》2021年第1期197-203,共7页Genomics and Applied Biology

基　　金：四川省教育厅社科青年项目(18ZB0455)资助。

摘　　要：木聚糖酶是一类木聚糖降解酶系,在食品、饲料领域应用广泛。本实验对实验室前期保存的一株产木聚糖酶真菌TL01进行形态学、18S rDNA及产酶鉴定,其结果表明TL01为梳棉状嗜热真菌(Thermomyces lanuginosus),以木糖为底物,测得粗酶液酶活为0.250±0.03 U/m L。对其两种主要的木聚糖酶基因(xyn11A和xyl43)进行克隆并对其编码蛋白(Xyn11A和Xyl43)进行了生物信息学分析。Xyn11A预测蛋白分子量24.36 kD,等电点为4.77,含有19个氨基酸的信号肽序列,属于亲水性蛋白,无跨膜结构域,其二级结构主要是无规则卷曲(44.89%);Xyl43蛋白分子量38.24 kD,等电点为5.23,编码的胞内蛋白属于亲水性蛋白,无跨膜结构域,无规则卷曲(59.76%)是其主要的二级结构。本研究通过对Th. lanuginosus TL01的xyn11A和xyl43基因克隆及其编码蛋白的生物信息学分析,为后续进一步构建高效表达工程菌株奠定了基础。Xylanase is a kind of xylan degrading enzyme system, which is widely used in the fields of food and feed.In this experiment, an xylanase-producing fungus TL01, which was stored in the laboratory, was identified by morphology, 18S rDNA and enzyme production. The results showed that TL01 was a Thermomyces lanuginosus, the enzyme activity of the crude enzyme solution was 0.250 ± 0.03 U/mL, which was measured with xylose as a substrate.The two main xylanase genes(xyn11A and xyl43) were cloned and their encoded proteins(Xyn11A and Xyl43)were analyzed by bioinformatics. The Xyn11A protein had a molecular weight of 24.36 kD, an isoelectric point of 4.77,and a signal peptide sequence of 19 amino acids. This protein was a hydrophilic protein with no transmembrane domain. Its secondary structure was mainly composed of random coil(44.89%). Otherwise, the molecular weight of protein Xyl43 was 38.24 kD and isoelectric point was 5.23, the protein was a hydrophilic protein with no transmembrane domain. Its secondary structure was mainly composed of random coil(59.76%). In this study, the xyn11A and xyl43 gene clones of Th. lanuginosus TL01 and the bioinformatics analysis of their encoded proteins will lay a foundation for the further construction of high-efficiency expression engineering strains in the future.

关 键 词：耐热木聚糖酶 鉴定 基因克隆 生物信息学 

分 类 号：Q78[生物学—分子生物学]