Functional analysis of the aefR mutation and identification of its binding site in Pseudomonas syringae pv, tabaci 11528

• Published in: Acta biochimica et biophysica Sinica 2015-11, Vol.47 (11), p.938-945
• Main Authors: Yun, Sora, Lee, Jun Seung, Do, Mi Sol, Jeon, Young Ji, Cha, Ji Young, Baik, Hyung Suk
• Format: Article
• Language: English
• Subjects: Bacterial Proteins - metabolism; Mutation; Pseudomonas syringae; Pseudomonas syringae - genetics; Pseudomonas syringae - metabolism; Quorum Sensing; Real-Time Polymerase Chain Reaction; Regulatory Elements, Transcriptional; 丁香假单胞菌; 基因表达; 监狱; 粉虱; 结合位点; 缺失突变株; 聚合酶链反应; 识别
• ISSN: 1672-9145; 1745-7270
• DOI: 10.1093/abbs/gmv091

The TetR family transcriptional regulator AefR contributes to the regulation of the quorum-sensing system. However, the role of AefR in the regulatory network of the phytopathogen Pseudomonas syringae pathovars is not known. In this study, the phenotype of a P. syringae pv. tabaci 11528 aefR deletion mutant strain was examined. The aefR gene expression and AefR DNA-binding affinity were examined by quantitative real-time polymerase chain reaction and electrophoretic mobility shift assay, respectively. AefR was found to control quorum-sensing genes as well as the efflux genes mexE, mexF, and oprN via an indirect mechanism. AefR binds to its own operator site as well as to the palindromic sequence between positions -28 and -2 corresponding to the transcription start site of aefR, as determined by dye primer sequencing. These results suggest that P. syringae AefR modulates quorum sensing and efflux as well as its own expression, which can be exploited by strategies developed to manage this plant parasite.