1. DNA-binding directs the localization of a membrane-integrated receptor of the ToxR family.
- Author
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Brameyer S, Rösch TC, El Andari J, Hoyer E, Schwarz J, Graumann PL, and Jung K
- Subjects
- Amino Acid Transport Systems metabolism, Antiporters metabolism, Binding Sites, Cadaverine metabolism, Escherichia coli Proteins genetics, Hydrogen-Ion Concentration, Lac Operon genetics, Luminescent Proteins metabolism, Lysine metabolism, Microscopy, Fluorescence methods, Protein Binding, Time-Lapse Imaging methods, Trans-Activators genetics, Red Fluorescent Protein, Bacterial Proteins metabolism, Cell Membrane metabolism, DNA-Binding Proteins metabolism, Escherichia coli chemistry, Escherichia coli Proteins metabolism, Trans-Activators metabolism, Transcription Factors metabolism
- Abstract
All living cells have a large number of proteins that are anchored with one transmembrane helix in the cytoplasmic membrane. Almost nothing is known about their spatiotemporal organization in whole cells. Here we report on the localization and dynamics of one representative, the pH sensor and transcriptional regulator CadC in Escherichia coli . Fluorophore-tagged CadC was detectable as distinct cluster only when the receptor was activated by external stress, which results in DNA-binding. Clusters immediately disappeared under non-stress conditions. CadC variants that mimic the active state of CadC independent of environmental stimuli corroborated the correlation between CadC clustering and binding to the DNA, as did altering the number or location of the DNA-binding site(s) in whole cells. These studies reveal a novel diffusion-and-capture mechanism to organize a membrane-integrated receptor dependent on the DNA in a rod-shaped bacterium., Competing Interests: The authors declare no competing interests.
- Published
- 2019
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