一个长69.9kb的反向重复增加了Lactobacillus crispatus菌株的基因组不稳定性
Lorenzo Colombini1, Francesco Santoro1, Mariana Tirziu1
1Laboratory of Molecular Microbiology and Biotechnology, Department of Medical Biotechnologies, University of Siena, 53100 Siena, Italy.
NAR genomics and bioinformatics
|June 27, 2025
概括
在 Lactobacillus crispatus M247_Siena 中发现了超过 30 kb 的罕见长时间倒置重复 (LIR). 这些LIR显著增加了基因组的不稳定性,表明这可能是一个全物种的特征.
科学领域:
- 微生物学 微生物学
- 基因组学就是基因组学.
- 分子生物学分子生物学
背景情况:
- 长反转重复 (LIR) 是超过30kb的DNA序列,在 prokaryotic 基因组中很少观察到.
- 乳杆菌crispatus是一种具有潜在益生菌应用的物种,使其基因组稳定性成为研究的关键领域.
研究的目的:
- 在Lactobacillus crispatus M247_Siena中识别和描述LIR.
- 调查这些LIR对基因组稳定性的影响.
- 探索Lactobacillus crispatus物种中基因组不稳定性和LIR的流行情况.
主要方法:
- 使用纳米孔和Illumina技术进行全基因组测序.
- 超长纳米孔读取映射用于基因组结构分析.
- 聚合酶连锁反应 (PCR) 用于人口分析和验证.
主要成果:
- 在L. crispatus M247_Siena中发现了两种69.9kb的LIR,这种LIR在父系M247菌株中不存在.
- 这些LIR的存在导致M247_Siena显著的基因组不稳定,在高频率检测到的替代染色体结构.
- 对比分析显示,在其他L. crispatus基因组中没有类似的LIR,但与插入序列相关的其他长重复和重排是常见的.
结论:
- 在L. crispatus M247_Siena中发现的LIR是一种新发现,也是基因组不稳定的主要驱动因素.
- 基因组不稳定性,通常由插入序列和长时间的重复介导,似乎是Lactobacillus crispatus物种的特征特征.
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