成熟域向信号 (MTSs) 在乳球菌中蛋白质转位和分泌的作用
Mai Ngoc Hoang1, Clemens Peterbauer1
1Institute of Food Technology, Department of Food Science and Technology, BOKU University, 1190 Vienna, Austria.
International journal of molecular sciences
|January 11, 2025
概括
改造的乳球球菌 (Lactococcus lactis) 在疫苗输送方面表现有前途. 优化蛋白质分泌和细胞表面定是关键,成熟域向信号 (MTSs) 在融合蛋白有效性中起着至关重要的作用.
科学领域:
- 微生物学和生物技术
- 蛋白质工程是指蛋白质工程.
- 疫苗开发 疫苗开发
背景情况:
- 乳球菌 (Lactococcus lactis) 是一个有前途的细菌细胞工厂,用于生产疫苗和治疗性蛋白质.
- 目前对工程L. lactis的应用显示出治疗炎症性肠病和宫癌的潜力.
- 在L. lactis中提高蛋白质分泌和细胞定效率仍然是改善的关键领域.
研究的目的:
- 调查成熟域向信号 (MTS) 在L. lactis.融合蛋白的分泌和细胞表面显示中的作用.
- 为了评估基本膜蛋白A (BmpA) 与人类乳头瘤病毒 (HPV) 16 E7 oncoprotein 融合的不同截断结构的影响.
- 探索合理设计改进的融合蛋白结构以提高效率的策略.
主要方法:
- 开发一种双重标记方法,使用比亚森头针结合和-多胺亲和力来可视化和量化蛋白质.
- 生成截断的BmpA结构 (126,66和26个氨基酸) 与HPV16 E7基蛋白融合.
- 在工程L. lactis中分析蛋白质贩运,细胞表面定和细胞质局部化.
主要成果:
- 融合蛋白的过度表达对L. lactis细胞增殖产生了负面影响.
- 最短的融合蛋白 (26个氨基酸) 是L. lactis难以生产和显示的,这表明MTS对于出口和定至关重要.
- 具有40个氨基酸和一个MTS的融合蛋白显示出有效的转位;突变增加MTS的疏水性,增强分泌和表面显示.
结论:
- 对于高效的蛋白质出口和在工程L. lactis.中进行表面定,MTS的存在至关重要.
- 合理的设计,包括优化MTS疏水性,可以显著改善融合蛋白的分泌和细胞表面显示.
- 这些发现为开发更有效的基于L. lactis的疫苗和治疗药物的输送系统提供了基础.
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