Cyclic-di-GMP Regulates the Quorum-Sensing System and Biocontrol Activity of Pseudomonas fluorescens 2P24 through the RsmA and RsmE Proteins
Cyclic-di-GMP Regulates the Quorum-Sensing System and Biocontrol Activity of Pseudomonas fluorescens 2P24 through the RsmA and RsmE Proteins
复制标题
Cyclic-di-GMP 通过 RsmA 和 RsmE 蛋白调节荧光假单胞菌 2P24 的群体感应系统和生物防治活性。
DOI：
10.1128/aem.02016-20
复制
发表时间：
2020-12-01
影响因子：
4.4
通讯作者：
Wu, Xiaogang
中科院分区：
文献类型：
--
作者：
Liang, Fei;Zhang, Bo;Wu, Xiaogang
荧光假单胞菌 2P24 是一种根际细菌，可保护许多农作物免受植物病原体引起的土传疾病。 Pcol/PcoR 群体感应 (QS) 系统和聚酮化合物抗生素 2,4-二乙酰基间苯三酚 (2,4-DAPG) 与该菌株的生物防治潜力特别相关。在本研究中，我们研究了 c-di-GMP 对菌株 2P24 生防活性的影响。荧光假单胞菌2P24中大肠杆菌二鸟苷酸环化酶(YedQ)和磷酸二酯酶(YhjH)的表达分别显着增加和降低了c-di-GMP的细胞浓度。在 2P24 中，QS 信号 N-酰基高丝氨酸内酯 (AHL) 和 2,4-DAPG 的产生受到 c-di-GMP 的负调节。调节蛋白RsmA 和RsmE 受到c-di-GMP 的正向调节。基因组分析显示，2P24 有 23 个预测蛋白，其中包含 c-di-GMP 合成或降解结构域。在这些蛋白质中，C0J56_12915、C0J56_13325 和 C0156_27925 有助于 c-di-GMP 的产生，并且还参与荧光假单胞菌中 QS 信号和抗生素 2,4-DAPG 产生的调节。 C0156_12915、C0J56_13325 和 C0156_27925 在 2P24 中的过度表达损害了其根部定殖和生物防治活性。综上所述，这些结果表明 c-di-GMP 在微调荧光假单胞菌的生防性状方面发挥着重要作用。 重要性 在各种细菌中，细菌第二信使 c-di-GMP 影响广泛的细胞过程。然而，c-di-GMP 对植物有益的根际细菌的生物防治性状的功能仍不清楚。目前的工作表明，荧光假单胞菌 2P24 中的 QS 系统和聚酮化合物抗生素 2,4-DAPG 的产生受 c-di-GMP 通过 RsmA 和 RsmE 蛋白的调节。二鸟苷酸环化酶 (DGC) C0J56_12915、C0156_13325 和 C0156_27925 特别参与调节 2P24 的生物防治性状。我们的工作还证明了荧光假单胞菌中 Gac/Rsm 级联与 c-di-GMP 信号通路之间的联系。
Pseudomonas fluorescens 2P24 is a rhizosphere bacterium that protects many crop plants against soilborne diseases caused by phytopathogens. The Pcol/PcoR quorum-sensing (QS) system and polyketide antibiotic 2,4-diacetylphloroglucinol (2,4-DAPG) are particularly relevant to the strain's biocontrol potential. In this study, we investigated the effects of c-di-GMP on the biocontrol activity of strain 2P24. The expression of the Escherichia coil diguanylate cyclase (YedQ) and phosphodiesterase (YhjH) in P. fluorescens 2P24 significantly increased and decreased the cellular concentration of c-di-GMP, respectively. The production of the QS signals N-acyl homoserine lactones (AHLs) and 2,4-DAPG was negatively regulated by c-di-GMP in 2P24. The regulatory proteins RsmA and RsmE were positively regulated by c-di-GMP. Genomic analysis revealed that 2P24 has 23 predicted proteins that contain c-di-GMP-synthesizing or -degrading domains. Among these proteins, C0J56_12915, C0J56_13325, and C0156_27925 contributed to the production of c-di-GMP and were also involved in the regulation of the QS signal and antibiotic 2,4-DAPG production in P. fluorescens. Overexpression of C0156_12915, C0J56_13325, and C0156_27925 in 2P24 impaired its root colonization and biocontrol activities. Taken together, these results demonstrated that c-di-GMP played an important role in fine-tuning the biocontrol traits of P. fluorescens.IMPORTANCE In various bacteria, the bacterial second messenger c-di-GMP influences a wide range of cellular processes. However, the function of c-di-GMP on biocontrol traits in the plant-beneficial rhizobacteria remains largely unclear. The present work shows that the QS system and polyketide antibiotic 2,4-DAPG production are regulated by c-di-GMP through RsmA and RsmE proteins in P. fluorescens 2P24. The diguanylate cyclases (DGCs) C0J56_12915, C0156_13325, and C0156_27925 are especially involved in regulating the biocontrol traits of 2P24. Our work also demonstrated a connection between the Gac/Rsm cascade and the c-di-GMP signaling pathway in P. fluorescens.