黑曲霉mnn9基因缺失株的构建及其功能分析

Construction and functional analysis of the mnn9 gene disruption mutant in Aspergillus niger

本研究通过分析比较黑曲霉基因组与酿酒酵母基因组序列同源性,分离鉴定了黑曲霉mnn9基因。通过同源重组,在黑曲霉GICC2773(ΔAP4:pGPT-laccase)菌株中敲除了mnn9基因。该黑曲霉mnn9基因缺失使外源蛋白漆酶的分泌表达提高了14%,内源蛋白葡萄糖淀粉酶的分泌表达则降低了4%。

Here we use a comparative genomics approach to isolate mnn9 gene from Aspergillus niger which share high homology with S. cerevisiae mnn9 encoding mannosyltransferase responsible for the majority of the a-1,6-polymerizing activity of the mannoprotein . By double crossover, mnn9 gone in Aspergillus niger GICC2773 （△AP4： pGPT-laccase） strain was knocked out. Like all members of the S. cerevisiae mnn9 disruption mutant, in Aspergillus niger the mnn9 gene disruption mutant enhances heterologous protein laocase production by about 14% as compared with the parental strains, but decreases homologous protein glucoamylase production by about 4%.