芽胞形成相关基因缺失对解淀粉芽胞杆菌生物量及胞外酶表达的影响

解淀粉芽胞杆菌作为公认的安全生产宿主菌(GRAS),在高效表达异源蛋白方面具有巨大的发展潜力和应用前景.本研究以解淀粉芽胞杆菌TCCC111018为出发菌株,通过敲除芽胞形成相关基因(spo0A,sigF和sigE),构建了一系列突变菌株(BA△spo0A,BA△sigF,BA△sigE),并对突变株生物量和胞外酶表达...

Effects of Spore Formation Related Gene Deletion on Biomass and Extracellular Enzyme Expression of Bacillus amyloliquefaciens

As a recognized safe(GRAS)bacterial hosts,Bacillus amyloliquefaciens has great development potential and application prospects in the efficient expression of heterologous enzyme.In this study,a series of B.amyloliquefaciens TCCC111018 mutant strains(BAΔspo0A,BAΔsigF,and BAΔsigE)were constructed by knocking out genes(spo0A,sigF and sigE)related to spore formation,and their biomasses and expressions of extracellular enzymes were analyzed and compared.The results showed that the biomass and extracellular enzyme expression of the strain BAΔspo0A were significantly reduced when compared with the starting strain BAΔupp,no obvious improvement for BAΔsigE,while the production performance of strain BAΔsigF was significantly improved.The stable phase of bacterial growth was prolonged by about 6 h,the time of producing enzyme was also advanced and the activity of acid-resistantα-amylase and alkaline protease were 25.23%and 21.3%higher than that of the control bacteria,respectively.The successful construction of BAΔsigF provides a new choice for industrial enzyme production hosts,also proposes a new strategy for the efficient production of heterologous enzymes.