含抗菌肽基因的天然质粒在枯草杆菌中的表达

发布时间：2018-02-05 22:45

  本文关键词： 侧孢短芽孢杆菌 天然质粒 异源表达 抗菌肽 抑菌效价　出处：《食品科学》2017年08期 　论文类型：期刊论文

【摘要】：侧孢短芽孢杆菌抗菌肽具有高效、广谱、稳定的抗菌活性,该抗菌活性与其内源质粒密切相关。为研究侧孢短芽孢杆菌含抗菌肽基因质粒异源表达的可行性,本研究中将侧孢短芽孢杆菌S62~-9的天然质粒电转枯草芽孢杆菌Wb800受体细胞,筛选阳性转化子并对其表达产物性质进行研究。得到了产生抗菌活性产物菌株Z4,发酵6 h后开始产生抗菌物质,12~20 h产量达到最大,达620.96 AU/m L。Tricine~-十二烷基硫酸钠~-聚丙烯酰胺凝胶电泳看到S62~-9质粒在枯草芽孢杆菌中得到了成功的表达,反相高效液相色谱分析Z4表达产物含有与侧孢短芽孢杆菌抗菌肽相同物质。该物质抑菌谱广,稳定性好:对于G~+、G~-和真菌均有抑菌活性,而且对于G~+菌株的抑菌效果优于G~-菌株和真菌,121℃处理20 min后的效价保留率约为90%,100℃处理60 min后仍有81%的活性保留;p H 2~12的范围内效价保留率基本不发生变化;对蛋白酶较为敏感,胰蛋白酶和蛋白酶K处理后抗菌肽的效价保留率为60%左右,其他3种蛋白酶处理后也有一定程度的降低。本研究获得了抗菌肽的异源表达菌株Z4,为进一步工业生产抗菌肽提供支持,而且为该抗菌肽遗传基因定位于质粒上提供了证明。
[Abstract]:The antimicrobial peptides of Bacillus parthenosporium have high efficiency, broad spectrum and stable antibacterial activity, which is closely related to its endogenous plasmids. This study is intended to study the feasibility of heterologous expression of antimicrobial peptide gene plasmids in Bacillus parthenosporium. In this study, the natural plasmids of Bacillus cereus S62C9 were electrotransferred into Wb800 receptor cells of Bacillus subtilis. The positive transformants were screened and the properties of the expressed products were studied. Strain Z4 was obtained and the production of the antibacterial substance began to reach the maximum at 20 h after fermentation for 6 h. As far as 620.96 AU/m L. Tricineto- 12 sodium alkyl sulfate and polyacrylamide gel electrophoresis, we can see that S62- 9 plasmid was successfully expressed in Bacillus subtilis (Bacillus subtilis). RP-HPLC analysis showed that the expressed product of Z4 contained the same substance as the antimicrobial peptide of Bacillus cereus. It had wide antibacterial spectrum and good stability. Moreover, the bacteriostasis effect of G- strain was better than that of G- strain and fungi treated at 121 鈩，

本文编号：1492958