Bedree Joseph K, Bourgeois Jacob, Balani Pooja, Cen Lujia, Hendrickson Erik L, Kerns Kristopher A, Camilli Andrew, McLean Jeffrey S, Shi Wenyuan, He Xuesong
Section of Oral Biology, Division of Oral Biology and Medicine, School of Dentistry, University of California-Los Angeles, Los Angeles, CA, 90095.
Department of Microbiology, The ADA Forsyth Institute; Cambridge, MA, 02142.
bioRxiv. 2024 Jul 18:2024.07.17.604004. doi: 10.1101/2024.07.17.604004.
The unique epibiotic-parasitic relationship between type strain TM7x, a member of the newly identified Candidate Phyla Radiation, now referred to as and its basibiont, strain XH001 (formerly , require more powerful genetic tools for deeper understanding of the genetic underpinnings that mediate their obligate relationship. Previous studies have mainly characterized the genomic landscape of XH001 during or post TM7x infection through comparative genomic or transcriptomic analyses followed by phenotypic analysis. Comprehensive genetic dissection of the pair is currently cumbersome due to the lack of robust genetic tools in TM7x. However, basic genetic tools are available for XH001 and this study expands the current genetic toolset by developing high-throughput transposon insertion sequencing (Tn-seq). Tn-seq was employed to screen for essential genes in XH001 under laboratory conditions. A highly saturated Tn-seq library was generated with nearly 660,000 unique insertion mutations, averaging one insertion every 2-3 nucleotides. 203 genes, 10.5% of the XH001 genome, were identified as putatively essential.
新鉴定的候选门辐射类群成员模式菌株TM7x与其宿主菌株XH001（原称 ）之间独特的体表寄生关系，需要更强大的遗传工具来深入了解介导其专性关系的遗传基础。以往的研究主要通过比较基因组或转录组分析以及表型分析，对TM7x感染期间或之后的XH001基因组格局进行了表征。由于TM7x缺乏强大的遗传工具，目前对这一对菌株进行全面的遗传剖析很繁琐。然而，XH001有基本的遗传工具，本研究通过开发高通量转座子插入测序（Tn-seq）扩展了当前的遗传工具集。Tn-seq用于在实验室条件下筛选XH001中的必需基因。构建了一个高度饱和的Tn-seq文库，有近660,000个独特的插入突变，平均每2 - 3个核苷酸有一个插入。203个基因（占XH001基因组的10.5%）被鉴定为可能是必需的。
