School of Natural Sciences, Macquarie University, Sydney, Australia.
ARC Centre of Excellence in Synthetic Biology, Macquarie University, Sydney, Australia.
Microb Genom. 2024 Mar;10(3). doi: 10.1099/mgen.0.001212.
Swimming motility is a key bacterial trait, important to success in many niches. Biocontrol bacteria, such as Pf-5, are increasingly used in agriculture to control crop diseases, where motility is important for colonization of the plant rhizosphere. Swimming motility typically involves a suite of flagella and chemotaxis genes, but the specific gene set employed for both regulation and biogenesis can differ substantially between organisms. Here we used transposon-directed insertion site sequencing (TraDIS), a genome-wide approach, to identify 249 genes involved in Pf-5 swimming motility. In addition to the expected flagella and chemotaxis, we also identified a suite of additional genes important for swimming, including genes related to peptidoglycan turnover, O-antigen biosynthesis, cell division, signal transduction, c-di-GMP turnover and phosphate transport, and 27 conserved hypothetical proteins. Gene knockout mutants and TraDIS data suggest that defects in the Pst phosphate transport system lead to enhanced swimming motility. Overall, this study expands our knowledge of pseudomonad motility and highlights the utility of a TraDIS-based approach for analysing the functions of thousands of genes. This work sets a foundation for understanding how swimming motility may be related to the inconsistency in biocontrol bacteria performance in the field.
游动性是细菌的一个关键特性，对许多生态位的成功都很重要。生防细菌，如 Pf-5，越来越多地被用于农业来控制作物病害，而在植物根际定殖时，游动性对其很重要。游动性通常涉及一套鞭毛和趋化性基因，但在不同生物体中，用于调节和生物发生的特定基因集可能有很大差异。在这里，我们使用转座子定向插入位点测序（TraDIS），一种全基因组方法，鉴定了 249 个与 Pf-5 游动性相关的基因。除了预期的鞭毛和趋化性外，我们还鉴定了一套与游动性相关的其他重要基因，包括与肽聚糖周转、O-抗原生物合成、细胞分裂、信号转导、c-di-GMP 周转和磷酸盐转运相关的基因，以及 27 个保守的假设蛋白。基因敲除突变体和 TraDIS 数据表明，Pst 磷酸盐转运系统的缺陷导致游动性增强。总的来说，这项研究扩展了我们对假单胞菌运动性的认识，并强调了基于 TraDIS 的方法在分析数千个基因功能方面的实用性。这项工作为理解游动性如何与生防细菌在田间表现的不一致性有关奠定了基础。
