These authors contributed equally to this work.
Characterization of the elongasome core PBP2 : MreC complex of Helicobacter pylori
Article first published online: 15 SEP 2011
© 2011 Blackwell Publishing Ltd
Volume 82, Issue 1, pages 68–86, October 2011
How to Cite
El Ghachi, M., Matteï, P.-J., Ecobichon, C., Martins, A., Hoos, S., Schmitt, C., Colland, F., Ebel, C., Prévost, M.-C., Gabel, F., England, P., Dessen, A. and Boneca, I. G. (2011), Characterization of the elongasome core PBP2 : MreC complex of Helicobacter pylori. Molecular Microbiology, 82: 68–86. doi: 10.1111/j.1365-2958.2011.07791.x
- Issue published online: 26 SEP 2011
- Article first published online: 15 SEP 2011
- Accepted manuscript online: 1 AUG 2011 05:14AM EST
- Accepted 26 July, 2011.
The definition of bacterial cell shape is a complex process requiring the participation of multiple components of an intricate macromolecular machinery. We aimed at characterizing the determinants involved in cell shape of the helical bacterium Helicobacter pylori. Using a yeast two-hybrid screen with the key cell elongation protein PBP2 as bait, we identified an interaction between PBP2 and MreC. The minimal region of MreC required for this interaction ranges from amino acids 116 to 226. Using recombinant proteins, we showed by affinity and size exclusion chromatographies and surface plasmon resonance that PBP2 and MreC form a stable complex. In vivo, the two proteins display a similar spatial localization and their complex has an apparent 1:1 stoichiometry; these results were confirmed in vitro by analytical ultracentrifugation and chemical cross-linking. Small angle X-ray scattering analyses of the PBP2 : MreC complex suggest that MreC interacts directly with the C-terminal region of PBP2. Depletion of either PBP2 or MreC leads to transition into spherical cells that lose viability. Finally, the specific expression in trans of the minimal interacting domain of MreC with PBP2 in the periplasmic space leads to cell rounding, suggesting that the PBP2/MreC complex formation in vivo is essential for cell morphology.