生物技术通报 ›› 2021, Vol. 37 ›› Issue (3): 35-43.doi: 10.13560/j.cnki.biotech.bull.1985.2020-0852

• 研究报告 • 上一篇    下一篇

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

李昕悦(), 张金方, 徐小健, 路福平, 李玉()   

  1. 天津科技大学生物工程学院 工业发酵微生物教育部重点实验室,天津 300457
  • 收稿日期:2020-07-11 出版日期:2021-03-26 发布日期:2021-04-02
  • 作者简介:李昕悦,男,硕士研究生,研究方向:发酵工程;E-mail:lixinyue941@126.com
  • 基金资助:
    国家重点研发计划(2017YFB0308401)

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

LI Xin-yue(), ZHANG Jin-fang, XU Xiao-jian, LU Fu-ping, LI Yu()   

  1. Key Laboratory of Industrial Fermentation Microbiology,Ministry of Education,College of Biotechnology,Tianjin University of Science & Technology,Tianjin 300457
  • Received:2020-07-11 Published:2021-03-26 Online:2021-04-02

摘要:

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(BAΔspo0A,BAΔsigF,BAΔsigE),并对突变株生物量和胞外酶表达量进行分析比较。结果表明,与出发菌株BAΔupp相比,菌株BAΔspo0A的生物量及胞外酶表达量显著降低,BAΔsigE无明显变化,而菌株BAΔsigF的生产性能有显著提升,菌体生长的稳定期延长约6 h,产酶时间提前,耐酸性α-淀粉酶与碱性蛋白酶酶活分别提高了25.2%和21.3%,该菌株的成功构建为工业酶生产宿主提供了新的选择,也为异源酶的高效生产提出了一种新的策略。

关键词: 解淀粉芽胞杆菌, 芽胞形成, 生物量, 耐酸性α-淀粉酶, 碱性蛋白酶

Abstract:

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-resistant α-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.

Key words: Bacillus amyloliquefaciens, spore formation, biomass, acid-resistant α-amylase, alkaline protease