埃舍里希亚大肠杆菌 (Escherichia coli Nissle 1917) 的超流菌株的构建和表征
Tomomi Sawabe1, Yoshihiro Ojima1, Mao Nakagawa1
1Department of Chemistry and Bioengineering, Graduate School of Engineering, Osaka Metropolitan University, Osaka, Japan.
PloS one
|April 2, 2024
概括
研究人员设计了益生菌Escherichia coli Nissle 1917 (EcN) 以显著增加外膜囊泡 (OMV) 产量. 这种通过基因淘汰实现的增强OMV生产,有望为开发改进的益生菌疗法提供希望.
科学领域:
- 微生物学 微生物学
- 细菌生理学 细菌生理学
- 益生菌 益生菌 益生菌
背景情况:
- 外膜囊泡 (OMVs) 对于格拉姆阴性细菌提供分子至关重要.
- 益生菌菌株Escherichia coli Nissle 1917 (EcN) 产生可以调节宿主免疫反应的OMV.
- 以前的研究表明,基因淘汰可以增强大肠杆菌K12中的OMV生产.
研究的目的:
- 在益生菌菌株Escherichia coli Nissle 1917 (EcN) 中增强外膜囊泡 (OMV) 生产.
- 研究双基因淘汰 (mlaE和nlpI) 对EcN的OMV生产和细胞形态学的影响.
主要方法:
- 基因工程:在EcN中对 mlaE和 nlpI进行双基因淘汰.
- 显微镜:快速结,深度蚀刻复制电子显微镜可可视化细胞结构和糖.
- 生物化学分析:对OMV的量化和对糖成分的分析.
- 活力测试:在正常培养条件下评估细胞活力.
主要成果:
- 与野生类型相比,工程化DmlaEΔnlpI EcN菌株的OMV产量大约高出8倍.
- 电子显微镜揭示了细胞延长,等离子溶解,并且在ΔmlaEΔnlpI EcN细胞的糖层中显著增加了洞.
- 虽然细胞活力下降,但在正常条件下,ΔmlaEΔnlpI突变体保持了生长.
- 펩티도글리칸的数量减少了一半,但它的氨基酸成分保持不变.
结论:
- mlaE和nlpI的双基因淘汰有效地提高了EcN中的OMV生产.
- 观察到的二醇糖的结构变化与过度流动有关.
- 具有增加OMV产量的工程EcN菌株是增强益生菌应用的有希望的候选人.
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