Zhang Shuaibing, Schlabach Kevin, Pérez Carrillo Victor Hugo, Ibrahim Anan, Nayem Shahran, Komor Anna, Mukherji Ruchira, Chowdhury Somak, Reimer Lisa, Trottmann Felix, Vlot A Corina, Hertweck Christian, Hellmich Ute A, Stallforth Pierre
Leibniz Institute for Natural Product Research and Infection Biology-Hans Knöll Institute, Department of Paleobiotechnology, Beutenbergstraße 11a, 07745 Jena, Germany.
Friedrich Schiller University Jena, Institute for Organic Chemistry and Macromolecular Chemistry, Humboldtstraße 10, 07743 Jena, Germany.
Cell. 2025 May 1;188(9):2495-2504.e20. doi: 10.1016/j.cell.2025.02.033. Epub 2025 Apr 2.
Amoebal predation exerts a strong evolutionary selection pressure on bacteria, thus driving the development of effective predator-defense strategies. However, little is known about the molecular interplay between bacteria and predators, particularly how bacteria can sense and kill their microbial predators. We show how the ubiquitous bacterium Pseudomonas syringae detects and kills the social amoeba Polysphondylium pallidum. Combining comparative genomics, molecular biology, and chemical analyses, we identified a chemical radar system. The system relies on P. syringae secreting the lipopeptide syringafactin, which is deacylated by the amoeba. The resulting peptides are sensed via the bacterial sensor protein chemical radar regulator (CraR) that activates genes for converting the predator-derived signal into the amoebicide pyrofactin. This system is widespread in P. syringae and enables bacteria to infect A. thaliana in the presence of amoebae. Our study advances the understanding of microbial sensing and opens new avenues for the discovery of natural products.
变形虫捕食对细菌施加了强大的进化选择压力，从而推动了有效的捕食者防御策略的发展。然而，对于细菌与捕食者之间的分子相互作用，尤其是细菌如何感知并杀死其微生物捕食者，我们知之甚少。我们展示了无处不在的丁香假单胞菌如何检测并杀死社会性变形虫苍白聚孢黏菌。通过结合比较基因组学、分子生物学和化学分析，我们鉴定出了一种化学雷达系统。该系统依赖于丁香假单胞菌分泌脂肽丁香菌素，而丁香菌素会被变形虫去酰化。产生的肽通过细菌传感器蛋白化学雷达调节因子（CraR）被感知，CraR会激活将捕食者衍生信号转化为杀变形虫素热菌素的基因。该系统在丁香假单胞菌中广泛存在，并使细菌能够在有变形虫存在的情况下感染拟南芥。我们的研究推进了对微生物感知的理解，并为天然产物的发现开辟了新途径。
