链球菌中的tRNA修饰景观:共享损失和类特异性适应
Ho-Ching Tiffany Tsui1, Chi-Kong Chan2,3, Yifeng Yuan4
1Department of Biology, Indiana University Bloomington, Bloomington, Indiana, USA.
bioRxiv : the preprint server for biology
|November 24, 2025
概括
这项研究绘制了Streptococcus病原体的tRNA修饰图,揭示了铁硫酶依赖的修饰和独特的代谢途径的损失. 基本修饰基因的差异突出了它们在细菌转化控制中的关键作用.
科学领域:
- 微生物学 微生物学
- 分子生物学分子生物学
- 基因组学就是基因组学.
背景情况:
- 转移RNA (tRNA) 修改对于细菌的转化控制和基因表达至关重要.
- 像Streptococcus mutans和Streptococcus pneumoniae这样的阳性病原体具有独特的tRNA修饰配置文件.
研究的目的:
- 在S. mutans和S. pneumoniae中全面映射tRNA修饰基因.
- 调查这些修饰和相关酶的功能意义.
- 为了比较跨链球菌种的tRNA修饰途径.
主要方法:
- 遗传学 是一个遗传学.
- 质谱测量质量谱测量
- 史诗转录组学 史诗转录组学
- 进行比较的基因组学.
- 基本性概况分析
主要成果:
- 这两种物种都表现出减少的铁硫酶依赖的tRNA修饰.
- 在S. pneumoniae中绘制了特定修饰 (D,m1A,m7G,t6A,i6A),DusB1被确定为唯一的D修饰酶.
- 观察到不同的queuosine (Q) 代谢途径:S. mutans合成Q de novo,而S. pneumoniae则在preQ1.
- 对比基因组学揭示了1,599种链球菌基因组的Q代谢策略.
- N-threonylcarbamoyladenosine (t6A) 合成酶 TsaE 在 S. pneumoniae 中是必不可少的,但不是 S. mutans.
- 在asnS (编码AsnRS) 中的抑制器突变部分恢复了 ΔtsaE 突变的活力.
结论:
- 在S. mutans和S. pneumoniae之间,tRNA修饰模式显著不同,反映了中央代谢和酶利用中的适应.
- 这项研究强调了tRNA修饰在氨基酸-tRNA合成酶识别和细菌活性的功能重要性.
- 对比分析提供了对Streptococcus属内tRNA修饰途径的进化和保存的见解.
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