为乳酸细菌开发Zn2+受控表达系统及其在工程益生菌中的应用
Xiaoning Xu1, Lingwen Zhang1, Yue Cui1
1State Key Laboratory of Microbial Technology, Shandong University, No. 72 Binhai Road, Qingdao, 266237, PR China.
Synthetic and systems biotechnology
|February 8, 2024
概括
在*Streptococcus thermophilus*中发现了一种新的Zn2+受控基因表达 (ZICE) 系统. 这种食品级系统能够精确控制*Lactococcus lactis*和*S. thermophilus*等工程益生菌中的基因表达.
科学领域:
- 微生物学 微生物学
- 分子生物学分子生物学
- 生物技术是生物技术.
背景情况:
- 乳球菌 (Lactococcus lactis) 和热菌 (Streptococcus thermophilus) 是工程益生菌的主要宿主.
- 食品级遗传工具的有限可用性限制了它们的应用.
- 开发新的,可控制的表达系统对于益生菌工程至关重要.
研究的目的:
- 确定和描述Streptococcus thermophilus中一种新的食品级基因表达系统.
- 评估Zn2+控制基因表达 (ZICE) 系统在L. lactis和S. thermophilus中调节基因表达的疗效.
- 为了证明ZICE系统在构建用于治疗性蛋白质分泌的工程益生菌中的实用性.
主要方法:
- 在S. thermophilus中识别了一种对Zn2+有反应的调节剂 (SczA) 和促进剂 (PczcD).
- 电泳运动转移试验 (EMSA) 证实SczA与促进区结合.
- 在L. lactis和S. thermophilus中构建和描述记者菌株 (GFP) 和功能菌株 (IL-10).
- 诱导条件的优化,包括Zn2+度和介质组成.
主要成果:
- 由SczA和PczcD组成的ZICE系统证明了特定的Zn2+-依赖基因调节.
- 在L. lactis和S. thermophilus中,绿色光蛋白 (GFP) 表达被Zn2+成功诱导,在它缺席时没有表达.
- 确定了最佳的Zn2+度 (L. lactis的0.8mM,S. thermophilus的0.16mM).
- 省略酵母提取物粉显著提高了GFP表达的2.2倍.
- 改造的L. lactis成功分泌了互白素-10 (IL-10),达到由尼控制系统驱动的表达水平的59.37%.
结论:
- 一种新的,食品级的Zn2+受控基因表达 (ZICE) 系统已经成功地被识别和表征.
- 齐斯 (ZICE) 系统为L. lactis和S. thermophilus的基因表达提供了一种强大而严格监管的方法.
- 这种系统具有很大的潜力,可以为各种应用开发先进的工程益生菌,包括治疗性蛋白质输送.
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