由细菌的寡糖转移酶对折叠蛋白质进行N结合的糖化
Michael Kowarik1, Shin Numao, Mario F Feldman
1Institute of Microbiology, Department of Biology, Eidgenössische Technische Hochschule (ETH) Zurich, 8093 Zurich, Switzerland.
概括
细菌N结合蛋白质糖化发生独立于蛋白质转位. 与真核生物不同,细菌系统高效地糖化折叠蛋白质,这表明这种必不可少的蛋白质修饰具有独特的进化途径.
科学领域:
- 生物化学 生物化学
- 分子生物学分子生物学
- 微生物学 微生物学
背景情况:
- N-链接蛋白质糖化是生命的所有领域中关键的翻译后修饰.
- 在真核生物中,它是分泌和膜蛋白的丰富来源,与转位和折叠相结合.
- 细菌机制及其与蛋白质折叠的关系仍然不太清楚.
研究的目的:
- 为了研究细菌中N结合蛋白质糖化酶的机制.
- 为了比较细菌糖化与真核生物共翻译过程.
- 为了确定细菌糖化是否依赖于蛋白质转位机制.
主要方法:
- 在实验室中使用细菌寡糖糖转移酶进行糖化分析.
- 在折叠和展开的内源和外源基质蛋白上测试糖化效率.
- 基质蛋白质构成的分析 (折叠与展开) 与糖化相关.
主要成果:
- 细菌的N-链糖化可以独立于蛋白质转位机制而发生.
- 细菌的寡糖转移酶有效地糖化了折叠的内源基质.
- 折叠的牛核糖酶A的糖化是低效的,但在展开时显著增加.
结论:
- 细菌的N-糖化不同于真核生物的共翻译机制.
- 细菌系统可能会在已经折叠的蛋白质上对柔性部位进行糖化.
- 欧核生物共翻译糖化演化以确保基质在折叠之前的灵活性,以进行高效的修改.
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