枯草芽孢杆菌胞外氨肽酶对菌体生长的作用研究

枯草芽孢杆菌胞外氨肽酶对菌体生长的作用研究

房月芹‘高新星2周哲敏2刘中美2*

}l江南大学环境与土木工程学院江苏无锡214122

}2江南大学生物工程学院江苏无锡214122

摘要:【目的】利用基因敲除技术构建突变菌株BS-AP-K来研究枯草芽孢杆菌的分泌型氨肽酶

对菌体生长的作用。【方法】基于X erldif重组系统敲除Bacillus subtilis 168基因组中ywaD基因，

研究比较野生型与BS-AP-K菌株在不同培养基中的生长情况。【结果】通过比较两菌株的生长情

况，发现敲除分泌型氨肽酶会对菌体生长带来不利影响，而这种影响可以通过在培养基中添加多

种游离氨基酸来弥补。【结论】研究结果表明胞外氨肽酶通过酶切外源蛋白质以及多肤来为细胞

生长提供营养所需。

关键词:枯草芽孢杆菌，氨肽酶，X erldif重组系统，基因敲除

Effect of secretory

          FANG Yue-Qin

aminopeptidase in Bacillus subtilis on the growth

GAO Xin-Xing2  ZHOU Zhe-Mine  LIU Zhong-Mei2*

      (1. School of Environment and Civil Engineering, Jiangnan I7niversity, Wuxi, Jiangsu 214122, China)

              (2. School of Biotechnology，Jiangnan I7niversity, Wuxi, Jiangsu 214122, China)

Abstract: [Objective] Aim to study the effect of secretory aminopeptidase in Bacillus subtilis 168 on

the growth, a gene knock-out mutant BS-AP-K was constructed. [Methods] based on the Xerldif

recombinant system, the ywaD gene was deleted from the genome. The growth of wild type and

BS-AP-K in different media was monitored. [Results] It turned out that the deletion of secretory

aminopeptidase had a negative effect on the growth of the strain. The impaired growth rate of BS-AP-K

strain can be overcome by amino acid supplements.  [Conclusion] This stu街indicated that the

secretory aminopeptidase played an important role in supplying amino acids required for growth by

坷drolyzing proteins or peptides.

Keywords: Bacillus subtilis, Aminopeptidase, Xer/difrecombinant system, Gene knock-out