Velasco-Gomariz Manuel, Sulzer Johannes, Faber Franziska, Fröhlich Kathrin S
Institute of Microbiology, Friedrich Schiller University, 07743 Jena, Germany.
Julius-Maximilians-University of Würzburg, Faculty of Medicine, Institute for Hygiene and Microbiology, 97080 Würzburg, Germany.
Nucleic Acids Res. 2025 Jan 7;53(1). doi: 10.1093/nar/gkae1139.
Small RNAs (sRNAs) play a crucial role in modulating target gene expression through short base-pairing interactions and serve as integral components of many stress response pathways and regulatory circuits in bacteria. Transcriptome analyses have facilitated the annotation of dozens of sRNA candidates in the ubiquitous environmental model bacterium Caulobacter crescentus, but their physiological functions have not been systematically investigated so far. To address this gap, we have established CauloSOEP, a multi-copy plasmid library of C. crescentus sRNAs, which can be studied in a chosen genetic background and under select conditions. Demonstrating the power of CauloSOEP, we identified sRNA AbnZ to impair cell viability and morphology. AbnZ is processed from the 3' end of the polycistronic abn mRNA encoding the tripartite envelope-spanning efflux pump AcrAB-NodT. A combinatorial approach revealed the essential membrane translocation module TamAB as a target of AbnZ, implying that growth inhibition by AbnZ is linked to repression of this system.
小RNA（sRNA）通过短碱基配对相互作用在调节靶基因表达中发挥关键作用，并作为细菌中许多应激反应途径和调控回路的重要组成部分。转录组分析有助于在普遍存在的环境模式细菌新月柄杆菌中注释数十个sRNA候选物，但到目前为止它们的生理功能尚未得到系统研究。为了填补这一空白，我们建立了CauloSOEP，这是一个新月柄杆菌sRNA的多拷贝质粒文库，可在选定的遗传背景和特定条件下进行研究。通过展示CauloSOEP的作用，我们鉴定出sRNA AbnZ会损害细胞活力和形态。AbnZ是从编码三联跨膜外排泵AcrAB-NodT的多顺反子abn mRNA的3'末端加工而来。一种组合方法揭示了必需的膜转运模块TamAB是AbnZ的靶标，这意味着AbnZ对生长的抑制与该系统的抑制有关。
