阿魏酸酯酶在黑曲霉中的同源表达
Homologous expression of ferulic acid esterase in Aspergillus niger
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摘要: 利用食品级黑曲霉表达系统同源表达阿魏酸酯酶是提高阿魏酸酯酶产量、降低生产成本的有效途径。利用PCR技术扩增黑曲霉阿魏酸酯酶A基因(faeA)的编码区,构建黑曲霉表达载体pSZHG-faeA,并通过农杆菌介导法转化黑曲霉。经筛选获得将faeA基因整合到糖化酶基因位点的同源重组转化子4株。在酶摇瓶发酵条件下,重组菌株培养液上清中的阿魏酸酯酶活性最高达18.6mU/mL。SDS-PAGE分析显示,4株重组菌株都有约36ku目的蛋白条带,表达量为188262μg/mL。结果表明,实现了阿魏酸酯酶在黑曲霉中的同源表达,为食品级阿魏酸酯酶的大规模工业化生产奠定了基础。Abstract: By using of food-grade Aspergillus niger expression system expressed ferulic acid esterase was an efficient path which could increase production of ferulic acid esterase and reduce production cost. Ferulic acid esterase (faeA) coding region in Aspergillus niger was cloned by the method of PCR, constructed Aspergillus niger expression vector pSZHG-faeA and transformed Aspergillus niger in the use of agrobacterium-mediated method. In the end, 4 positive homologous transformants were screened out, which the faeA gene was integrated into the glucoamylase gene locus. Engineering strain showed that glucoamylase fermentation condition of the engineering strain culture supernatant activity up to 18.6mU/mL. SDS-PAGE analysis showed that the 4 recombination strains were obviously different from starting strain, had about 36 ku interest protein band. The protein expression quality was 188 262μg/mL. The result indicated that this reserch realized homologous expression of ferulic acid esterase in Aspergillus niger. This research laid the foundation for mass industrial production of food-grade ferulic acid esterase.