Xu Ningna, Yu Shen, Moniot Sébastien, Weyand Michael, Blankenfeldt Wulf
Lehrstuhl für Biochemie, Universität Bayreuth, Universitätsstrasse 30, 95447 Bayreuth, Germany.
Acta Crystallogr Sect F Struct Biol Cryst Commun. 2012 Sep 1;68(Pt 9):1034-9. doi: 10.1107/S1744309112032538. Epub 2012 Aug 30.
The opportunistic bacterial pathogen Pseudomonas aeruginosa employs three transcriptional regulators, LasR, RhlR and PqsR, to control the transcription of a large subset of its genes in a cell-density-dependent process known as quorum sensing. Here, the recombinant production, crystallization and structure solution of the ligand-binding domain of PqsR (MvfR), the LysR-type transcription factor that responds to the Pseudomonas quinolone signal (PQS), a quinolone-based quorum-sensing signal that is unique to P. aeruginosa and possibly a small number of other bacteria, is reported. PqsR regulates the expression of many virulence genes and may therefore be an interesting drug target. The ligand-binding domain (residues 91-319) was produced as a fusion with SUMO, and hexagonal-shaped crystals of purified PqsR_91-319 were obtained using the vapour-diffusion method. Crystallization in the presence of a PQS precursor allowed data collection to 3.25 Å resolution on a synchrotron beamline, and initial phases have been obtained using single-wavelength anomalous diffraction data from seleno-L-methionine-labelled crystals, revealing the space group to be P6(5)22, with unit-cell parameters a = b = 116-120, c = 115-117 Å.
机会性细菌病原体铜绿假单胞菌利用三种转录调节因子LasR、RhlR和PqsR，在一种称为群体感应的细胞密度依赖性过程中控制其大量基因子集的转录。本文报道了PqsR（MvfR）配体结合结构域的重组表达、结晶及结构解析，PqsR是一种LysR型转录因子，可响应铜绿假单胞菌喹诺酮信号（PQS），这是一种基于喹诺酮的群体感应信号，为铜绿假单胞菌及可能少数其他细菌所特有。PqsR调节许多毒力基因的表达，因此可能是一个有吸引力的药物靶点。配体结合结构域（第91至319位氨基酸残基）作为与SUMO的融合蛋白表达，采用气相扩散法获得了纯化的PqsR_91-319的六边形晶体。在PQS前体存在下进行结晶，使得在同步加速器光束线上能够收集到分辨率为3.25 Å的数据，并利用硒代-L-甲硫氨酸标记晶体的单波长反常衍射数据获得了初始相位，结果表明空间群为P6(5)22，晶胞参数a = b = 116 - 120，c = 115 - 117 Å。
