Abstract：
Bacillus subtilis is regarded as a promising microbial expression system in bioengineering due to its high stress resistance, nontoxic, low codon preference and grow fast. The strain has a relatively efficient expression system, as it has at least three protein secretion pathways and abundant molecular chaperones, which guarantee its expression ability and compatibility. Currently, many proteins are expressed in Bacillus subtilis, and their application prospects are broad. Although Bacillus subtilis has great advantages compared with other prokaryotes related to protein expression and secretion, it still faces deficiencies, such as low wild-type expression, low product activity, and easy gene loss, which limit its large-scale application. Over the years, many researchers have achieved abundant results in the modification of Bacillus subtilis expression systems, especially the optimization of promoters, expression vectors, signal peptides, transport pathways and molecular chaperones. An optimal vector with a suitable promoter strength and other regulatory elements could increase protein synthesis and secretion, increasing industrial profits. This review highlights the research status of optimization strategies related to the expression system of Bacillus subtilis. Moreover, research progress on its application as a food-grade expression system is also presented, along with some future modification and application directions.
摘要：
枯草芽孢杆菌由于其高抗逆性,被认为是生物工程中很有前途的微生物表达系统。无毒,密码子偏好低，生长快。该菌株具有相对有效的表达系统，因为它至少有三条蛋白质分泌途径和丰富的分子伴侣，保证了其表达能力和兼容性。目前,许多蛋白质在枯草芽孢杆菌中表达，应用前景广阔。尽管与其他原核生物相比，枯草芽孢杆菌在蛋白质表达和分泌方面具有很大的优势，它仍然面临不足，如低野生型表达，产品活性低，和容易的基因丢失，限制了其大规模应用。多年来,许多研究人员在枯草芽孢杆菌表达系统的改造方面取得了丰富的成果,特别是启动子的优化，表达载体,信号肽，运输途径和分子伴侣。具有合适启动子强度和其他调控元件的最佳载体可以增加蛋白质的合成和分泌，提高工业利润。本文综述了枯草芽孢杆菌表达系统相关优化策略的研究现状。此外，还介绍了其作为食品级表达系统的应用研究进展，以及一些未来的修改和应用方向。
