黑暗物质由米 (Sinorhizobium meliloti) 携带的 phiLM21 类食原体
Maria E Vladimirova1, Marina L Roumiantseva1, Alla S Saksaganskaia1
1Laboratory of Genetics and Selection of Microorganisms, Federal State Budget Scientific Institution All-Russia Research Institute for Agricultural Microbiology (FSBSI ARRIAM), 196608 Saint Petersburg, Russia.
International journal of molecular sciences
|September 13, 2025
概括
大多数Sinorhizobium meliloti prophages (phiLM21-LPhs) 是碎片化的,与phiLM21菌体基因组有有限的重叠. 这些prophages含有重要的遗传"暗物质"与未知的功能,表明复杂的进化起源.
科学领域:
- 微生物学 微生物学
- 病毒学 病毒学
- 基因组学就是基因组学.
背景情况:
- Sinorhizobium meliloti是Fabaceae植物的一个关键的共生伙伴.
- 在S. meliloti种群中,phiLM21类的菌体 (phiLM21-LPhs) 普遍存在.
- 了解prophage多样性对于宿主-细菌相互作用至关重要.
研究的目的:
- 进行phiLM21-LPh核酸和氨基酸序列的比较分析.
- 研究这些菌体的基因组内容和整合模式.
- 探索传播遗传多样性的起源和功能影响.
主要方法:
- 来自36个S. meliloti菌株的25个phiLM21-LPhs的比较序列分析.
- 在宿主tRNA基因内识别集成的prophages.
- 对开放式阅读框架 (ORF) 和监管要素的分析.
主要成果:
- 菲LM21-LPhs的核酸序列仅覆盖了菲LM21基因组的34%.
- 细胞原体集成到tRNA基因中,但缺乏典型的tRNA-依赖性 lysogeny特征.
- 超过一半的预兆ORF具有未确定的功能 ("遗传暗物质").
- 菌体多样化可能是由于与其他菌体和细菌重组而产生的.
结论:
- 在S. meliloti中完好无损的phiLM21样体是高度碎片化和遗传多样化的.
- 它们的基因组中有很大一部分是具有未知的生物作用的'遗传暗物质'.
- 这种菌体多样性的进化途径和功能意义需要进一步研究.
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