转移RNA(tRNA)修饰在维持翻译保真度和效率方面发挥着至关重要的作用。它们可能在应激反应和毒力中起调节元件的作用。尽管他们的关键作用,对tRNA修饰及其相关合成基因的全面定位仍然有限,主要关注自由生活的细菌。在这项研究中,我们采用了多学科的方法,结合比较基因组学,质谱,和下一代测序,预测负责两种细胞内病原体-休斯顿巴尔通体I和图卢兹巴尔通体tRNA成熟的tRNA修饰基因集,是猫抓病和战壕热的病原体,分别。这一分析提出了挑战,特别是因为宿主的RNA污染,这是一个潜在的错误来源。然而,我们的方法预测了26个基因负责合成23个不同的tRNA修饰在B.henselae和22个基因与23个修饰相关。值得注意的是,类似于其他细胞内和共生细菌,两个巴尔通体物种都经历了tRNA修饰基因的大量减少,主要是通过简化34和37位的超修饰。巴尔通体表现出额外的四个修饰的损失,这些与基因衰变的例子有关,提供还原进化的快照。
Transfer RNA (tRNA) modifications play a crucial role in maintaining translational fidelity and efficiency, and they may function as regulatory elements in stress response and virulence. Despite their pivotal roles, a comprehensive mapping of tRNA modifications and their associated synthesis genes is still limited, with a predominant focus on free-living bacteria. In this study, we employed a multidisciplinary approach, incorporating comparative genomics, mass spectrometry, and next-generation sequencing, to predict the set of tRNA modification genes responsible for tRNA maturation in two intracellular pathogens-Bartonella henselae Houston I and Bartonella quintana Toulouse, which are causative agents of cat-scratch disease and trench fever, respectively. This analysis presented challenges, particularly because of host RNA contamination, which served as a potential source of error. However, our approach predicted 26 genes responsible for synthesizing 23 distinct tRNA modifications in B. henselae and 22 genes associated with 23 modifications in B. quintana. Notably, akin to other intracellular and symbiotic bacteria, both Bartonella species have undergone substantial reductions in tRNA modification genes, mostly by simplifying the hypermodifications present at positions 34 and 37. Bartonella quintana exhibited the additional loss of four modifications and these were linked to examples of gene decay, providing snapshots of reductive evolution.