双M蛋白系统具有不同的生物特征,但两者都对M18型A组链球菌的致病性有所贡献
Xiaorui Zhou1, Haoshuai Song1, Fei Pan1
1MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China; Ministry of Agriculture Key Laboratory of Animal Bacteriology, Nanjing 210095, China.
Microbes and infection
|August 19, 2023
概括
集团A链球菌 (GAS) M18菌株使用双M蛋白系统. 这些系统涉及GAS和GCSM蛋白质,对于这些细菌的毒性和皮肤病原性至关重要.
科学领域:
- 微生物学 微生物学
- 分子生物学分子生物学
- 细菌病原体的产生
背景情况:
- M蛋白质是A组链球菌 (GAS) 和C组链球菌 (GCS) 的关键表面毒性因子.
- M18型GAS菌株具有独特的双M蛋白系统,利用GAS (emm18) 和GCS (spa18) M蛋白.
- 在M18型GAS中的spa18基因与GCS szm基因相同.
研究的目的:
- 研究M18型GAS中双M蛋白系统的生物特征和毒性贡献.
- 分析 emm18 和 spa18 基因的转录调节.
- 了解M18和SPA18蛋白在细菌表面结构和宿主细胞相互作用中的不同作用.
主要方法:
- 对emm18和spa18进行比较基因分析.
- M18型GAS突变体 (Δemm18Δspa18) 的构造和特征.
- 使用电子显微镜评估细菌表面形态.
- 评估M18和SPA18蛋白结合特性和细胞毒性.
- 转录组分析以确定监管因素.
主要成果:
- 在M18型GAS中,spa18显示的转录水平高于emm18.
- 缺少两种M蛋白基因 (Δemm18Δspa18) 的突变者表现出光滑的表面,与野生型和单个突变菌株的粗表面不同.
- M18和SPA18蛋白显示出明显的结合特征和对巨细胞和角质细胞的差异性细胞毒性.
- emm18和spa18基因都对M18型GAS的皮肤致病性至关重要.
- 该mga基因可能调节spa18转录,SpyM18_2047可能发挥特定的调节作用.
结论:
- 在M18型GAS中,双M蛋白系统对细菌毒性和表面特征有显著的贡献.
- spa18是这个系统中高度转录的基因,在致病性方面发挥着至关重要的作用.
- M18和SPA18蛋白的独特功能性质调解与宿主细胞的相互作用.
- spa18的转录调节涉及MGA和SpyM18_2047等因素,提供了对毒性因子控制的见解.
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