摘要
通过基因敲除的方法构建spo0A基因缺失菌株,并评价spo0A基因缺失对克劳氏芽孢杆菌(Bacillus clausii)QL-1发酵生产性能的影响。经重叠延伸PCR和基因同源单交换技术,获得spo0A基因缺失突变株B. clausii QL-1△spo0A;通过系统比较spo0A基因敲除前后芽孢生成率、生物量及淀粉酶酶活的改变,发现B. clausii QL-1△spo0A菌株不产芽孢、生物量提高了24%,且B. clausii QL-1△spo0A发酵72 h淀粉酶酶活为1.58×105 U/g,淀粉酶活提高83.72%。说明克劳氏芽孢杆菌spo0A基因缺失对菌体生物量、芽孢生成率及代谢产物的生成等具有重要影响。
The spo0 A gene deletion strain was constructed by the gene knockout method, and the effect of spo0 A gene deletion on the fermentation performance of Bacillus clausii QL-1 was evaluated. Through overlap extension PCR and gene homologous single exchange technique, the spo0 A gene deletion mutant B. clausii QL-1△spo0 A was obtained. By systematically comparing the changes of the spore formation rate, biomass and amylase activity before and after spo0 A gene deletion, the results showed that strain B. clausii QL-1△spo0 A was asporulate, the biomass increased by24%, and the amylase activity of B. clausii QL-1△spo0 A was 1.58×105 U/g after fermentation for 72 h, which increased by 83.72%. It was found that B. clausii with spo0 A gene deletion had an important effect on the mycelia biomass, spore formation rate and metabolites generation.
引文
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