BswR controls bacterial motility and biofilm formation in Pseudomonas aeruginosa through modulation of the small RNA rsmZ.
Pseudomonas aeruginosa relies on cell motility and ability to form biofilms to establish infections; however, the mechanism of regulation remains obscure. Here we report that BswR, a xenobiotic response element-type transcriptional regulator, plays a critical role in regulation of bacterial motility and biofilm formation in P. aeruginosa. Transcriptomic and biochemical analyses showed that BswR counteracts the repressor activity of MvaT, controls the transcription of small RNA rsmZ and regulates the biogenesis of bacterial flagella. The crystal structure of BswR was determined at 2.3 Å resolution; the monomer comprises a DNA-binding domain with a helix-turn-helix motif in the N terminus and two helices (α6 and α7) with a V-shaped arrangement in the C-terminus. In addition to the contacts between the parallel helices α5 of two monomers, the two helical extensions (α6 and α7) intertwine together to form a homodimer, which is the biological function unit. Based on the result of DNase I protection assay together with structural analysis of BswR homodimer, we proposed a BswR-DNA model, which suggests a molecular mechanism with which BswR could interact with DNA. Taken together, our results unveiled a novel regulatory mechanism, in which BswR controls the motility and biofilm formation of P. aeruginosa by modulating the transcription of small RNA rsmZ.
Institute of Molecular and Cell Biology, 61 Biopolis Drive, 138673 Singapore, School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, 637551 Singapore and Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou 510642, China.
Chao
C
Wang
Fuzhou
F
Ye
Veerendra
V
Kumar
Yong-Gui
YG
Gao
Lian-Hui
LH
Zhang
D001426:Bacterial Proteins / Q000737:chemistry / Q000378:metabolism / Q000502:physiology*; D018441:Biofilms / Q000254:growth & development*; D010861:Fimbriae, Bacterial / Q000378:metabolism; D005407:Flagella / Q000378:metabolism; D015964:Gene Expression Regulation, Bacterial; D008124:Locomotion; D011401:Promoter Regions, Genetic; D011550:Pseudomonas aeruginosa / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D058727:RNA, Small Untranslated / Q000096:biosynthesis*; D015534:Trans-Activators / Q000502:physiology; D014157:Transcription Factors / Q000737:chemistry / Q000378:metabolism / Q000502:physiology*; D014158:Transcription, Genetic
D001426:Bacterial Proteins; C091100:GacA protein, Bacteria; C111692:MvaT protein, Pseudomonas; D058727:RNA, Small Untranslated; D015534:Trans-Activators; D014157:Transcription Factors