Gene Cloning and Heterologous Expression of a Novel Endoglucanase, Swollenin, from Trichoderma pseudokoningii S38
Gene Cloning and Heterologous Expression of a Novel Endoglucanase, Swollenin, from Trichoderma pseudokoningii S38
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DOI：
10.1271/bbb.80124
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发表时间：
2008-11
期刊：
影响因子：
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通讯作者：
Q. Yao;Tingting Sun;Weifeng Liu;Guanjun Chen
中科院分区：
文献类型：
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作者：
Q. Yao;Tingting Sun;Weifeng Liu;Guanjun Chen
从纤维素分解真菌Trichoderma pseudokoningii S38中分离到一种新的纤维素分解因子swollenin的编码序列。全长swo 2基因编码494个氨基酸的蛋白质，计算的分子量为51，393 Da，其中包括一个推定的22个氨基酸的信号肽。序列分析表明，分离的膨胀素与里氏木霉的膨胀素具有显著的同源性。在T.里氏QM 9414.表达的膨胀素蛋白随后通过两步离子交换层析纯化。纯化的膨胀素对木聚糖和酵母细胞壁葡聚糖有微弱的水解活性，而对羧甲基纤维素、棉纤维、滤纸和纤维素粉CF 11没有明显的水解活性。这些结果表明，虽然膨胀素保持未鉴定的糖水解活性，但它对纤维素中的β-1，4-糖苷键无活性。其在木质纤维素水解中的确切作用需要进一步分析。
The coding sequence of a novel cellulolytic factor, swollenin, was isolated from the cellulolytic fungus Trichoderma pseudokoningii S38. The full-length swo2 gene encodes a protein of 494 amino acids with a calculated molecular mass of 51,393 Da, which includes a putative 22-amino-acid signal peptide. Sequence analysis revealed significant identity between isolated swollenin and that from Trichoderma reesei. The swollenin gene was further expressed and purified in T. reesei QM9414. The expressed swollenin protein was consequently purified by two-step ion exchange chromatography. The purified swollenin had subtle hydrolytic activities on xylan and yeast cell wall glucan, while no apparent activities on carboxymethy cellulose, cotton fiber, filter paper, or cellulose powder CF11 were observed. These results indicate that although swollenin maintains unidentified glycohydrolytic activities, it is inactive against β-1,4-glycosidic bonds in cellulose. Its exact role in lignocellulose hydrolysis calls for further analysis.