Dickeyazeae是一种侵袭性细菌植物病原体,可感染多种寄主植物。据报道,整合宿主因子(IHF),由IHFα和IHFβ亚基组成的类核相关蛋白,通过影响类核结构和DNA弯曲来调节基因表达。为了确定IHF在玉米乳杆菌MS2发病机理中的作用,我们删除了IHF亚基编码基因ihfA和ihfB中的任一个。显著降低细胞壁降解酶(CWDEs)的产量,一种未知的新型植物毒素和毒力因子调节(VFM)群体感应(QS)信号,细胞运动性,生物膜的形成,以及此后对马铃薯片和香蕉幼苗的感染能力。为了表征与毒力相关的IHF蛋白的调节途径,预测了IHF结合位点(共有序列5'-WATCAANNNTTR-3'),并在整个基因组中发现了272个结合位点。110个受试基因的表达受IHF影响。电泳迁移率变化分析(EMSA)显示IhfA蛋白与vfmE启动子直接相互作用,spea,pipR,fis,SlyA,prtD,hrpL,公顷,hcp,indA,hdaa,flhD,pilt,gcpJ,arcA,arcB,和lysR。本研究通过控制VFM和腐胺QS信号的产生,阐明了IHF在D.zeae致病过程中的贡献,植物毒素,还有靛蓝,luxR-solo系统,Fis,Slya,和FlhD转录调节因子,和从I型到VI型的分泌系统。玉米D中IHF调节网络的表征为预防和控制植物软腐病提供了目标。
Dickeya zeae is an aggressive bacterial phytopathogen that infects a wide range of host plants. It has been reported that integration host factor (IHF), a nucleoid-associated protein consisting of IHFα and IHFβ subunits, regulates gene expression by influencing nucleoid structure and DNA bending. To define the role of IHF in the pathogenesis of D. zeae MS2, we deleted either and both of the IHF subunit encoding genes ihfA and ihfB, which significantly reduced the production of cell wall-degrading enzymes (CWDEs), an unknown novel phytotoxin and the virulence factor-modulating (VFM) quorum-sensing (QS) signal, cell motility, biofilm formation, and thereafter the infection ability towards both potato slices and banana seedlings. To characterize the regulatory pathways of IHF protein associated with virulence, IHF binding sites (consensus sequence 5\'-WATCAANNNNTTR-3\') were predicted and 272 binding sites were found throughout the genome. The expression of 110 tested genes was affected by IHF. Electrophoretic mobility shift assay (EMSA) showed direct interaction of IhfA protein with the promoters of vfmE, speA, pipR, fis, slyA, prtD, hrpL, hecB, hcp, indA, hdaA, flhD, pilT, gcpJ, arcA, arcB, and lysR. This study clarified the contribution of IHF in the pathogenic process of D. zeae by controlling the production of VFM and putrescine QS signals, phytotoxin, and indigoidine, the luxR-solo system, Fis, SlyA, and FlhD transcriptional regulators, and secretion systems from type I to type VI. Characterization of the regulatory networks of IHF in D. zeae provides a target for prevention and control of plant soft rot disease.