在Nanobdellati (以前的DPANN) 考古物及其宿主中的N相关蛋白质糖化
Satoshi Nakagawa1,2,3, Hiroyuki D Sakai4,5, Shigeru Shimamura2
1Division of Applied Biosciences, Laboratory of Marine Environmental Microbiology, Graduate School of Agriculture, Kyoto University, Kyoto, Japan.
Journal of bacteriology
|August 28, 2024
概括
Nanobdellati 古代生物为蛋白质修饰创造了他们自己的独特的细胞表面糖,使他们能够区分和粘附于特定的宿主细胞. 这一发现揭示了极端环境中的微生物相互作用.
科学领域:
- 微生物学 微生物学
- 生物化学 生物化学
- 考古研究 考古研究
背景情况:
- 纳米细菌 (原名DPANN细菌) 是极小的,基因组缩小的细菌,生活在异生关系中.
- 细胞粘附对于Nanobdellati生态生理学至关重要,可能是由细胞表面碳水化合物介导的糖化S层蛋白质.
- 了解Nanobdellati中宿主识别和粘附的分子基础是必不可少的,因为它们的家族遗传多样性和广泛分布.
研究的目的:
- 为了研究Nanobdellati及其古老宿主的糖蛋白组.
- 为了阐明蛋白质糖化在宿主细胞识别和粘附中的作用 Nanobdellati.
- 了解生态共生古生物中的甘氨酸合成和修饰机制.
主要方法:
- 对Nanobdellati及其宿主/非宿主古生物的共同培养和纯培养的糖蛋白组学分析.
- 在S层蛋白和其他甘氨酸蛋白上N链接甘氨酸的结构特征.
- 在Nanobdellati,宿主古生物和非宿主古生物之间对甘氨酸结构的比较分析.
主要成果:
- 与宿主相比,Nanobdellati拥有独特的葡萄糖蛋白与独特的葡萄糖,这表明它们可以自主合成葡萄糖.
- 在Nanobdellati中,糖化发生在N-X-S/T序列内的氨酸残留物上,类似于生命的其他领域.
- 主体古物N-甘氨酸具有独特的糖类 (脱氧素,非酸盐,酸盐),Nanobdellati可能用于区分宿主,在共同培养中显著缺少酸盐.
- 宿主和非宿主古生物中的S层蛋白质都被hexose,N-乙hexosamine和硫化deoxyhexose修饰.
结论:
- 纳米细胞自主合成它们自己的甘氨酸,可能使用宿主衍生基质,用于蛋白质修饰.
- 宿主古生物学上的独特的N-甘氨酸结构在使纳米细胞能够区分宿主和非宿主细胞之间发挥作用.
- 这项研究提供了对Nanobdellati的第一个葡萄糖蛋白质的见解,促进了对ectosymbiotic archaea中的分子相互作用的理解.
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