Origins of chemoreceptor curvature sorting in Escherichia coli.
Bacterial chemoreceptors organize into large clusters at the cell poles. Despite a wealth of structural and biochemical information on the system's components, it is not clear how chemoreceptor clusters are reliably targeted to the cell pole. Here, we quantify the curvature-dependent localization of chemoreceptors in live cells by artificially deforming growing cells of Escherichia coli in curved agar microchambers, and find that chemoreceptor cluster localization is highly sensitive to membrane curvature. Through analysis of multiple mutants, we conclude that curvature sensitivity is intrinsic to chemoreceptor trimers-of-dimers, and results from conformational entropy within the trimer-of-dimers geometry. We use the principles of the conformational entropy model to engineer curvature sensitivity into a series of multi-component synthetic protein complexes. When expressed in E. coli, the synthetic complexes form large polar clusters, and a complex with inverted geometry avoids the cell poles. This demonstrates the successful rational design of both polar and anti-polar clustering, and provides a synthetic platform on which to build new systems.
Biophysics Graduate Group and Department of Physics, University of California, Berkeley, California 94720, USA.|Bioengineering, Shriram Center for Bioengineering &Chemical Engineering, Stanford University, Stanford, California 94305, USA.
Will
W
Draper
Biophysics Graduate Group and Department of Physics, University of California, Berkeley, California 94720, USA.|Bioengineering, Shriram Center for Bioengineering &Chemical Engineering, Stanford University, Stanford, California 94305, USA.
Jan
J
Liphardt
D001426:Bacterial Proteins; D002462:Cell Membrane / Q000378:metabolism*; D016764:Cell Polarity; D048430:Cell Shape; D046508:Culture Techniques; D004926:Escherichia coli / Q000378:metabolism*; D029968:Escherichia coli Proteins / Q000378:metabolism*; D008164:Luminescent Proteins; D000072236:Methyl-Accepting Chemotaxis Proteins / Q000378:metabolism*; D008780:Methyltransferases / Q000378:metabolism; D011956:Receptors, Cell Surface / Q000378:metabolism*
D001426:Bacterial Proteins; D029968:Escherichia coli Proteins; D008164:Luminescent Proteins; D000072236:Methyl-Accepting Chemotaxis Proteins; D011956:Receptors, Cell Surface; C057331:Tar protein, E coli; C000607604:tsr protein, E coli; C054562:yellow fluorescent protein, Bacteria; C513923:CheR protein, E coli; D008780:Methyltransferases