Shape regulation in bacteria

How do microbes such as bacteria maintain their shapes? We are applying ideas from statistical mechanics and materials science to this interdisciplinary problem, in collaboration with our experimental colleagues. Previously we have shown, experimentally and theoretically, that mechanical stresses can strongly affect cell wall growth in bacteria. We are currently working on elucidating how such mechanical cues may aid bacteria in restoring their native forms when their shape is perturbed, and how the binding of proteins to membranes may act as curvature sensors. We are also developing models for processes such as bacterial lysis where the interplay of turgor pressure, cell wall and membrane physics lead to intriguing dynamics at the single-cell levels.

Relevant references:

  • Ariel Amir and Sven van Teeffelen, Getting into shape: how do rod-like bacteria control their geometry?, Systems and Synthetic Biology (special issue on cell division) 8, 227 (2014), invited article.
  • Ariel Amir and David R. Nelson, Dislocation-mediated growth of bacterial cell walls, Proceedings of the National Academy of Sciences 109, 9833 (2012), highlighted in Journal Club for Condensed Matter Physics (October 2013).
  • Ariel Amir, Farinaz Babaeipour, Dustin B. McIntosh, David R. Nelson and Suckjoon Jun, Bending forces plastically deform growing bacterial cell walls, Proceedings of the National Academy of Sciences 111, 5778 (2014), highlighted in Nature Physics 10 (2014).
  • Felix Wong, Lars Renner, Gizem Ozbaykal, Jayson Paulose, Douglas Weibel, Sven van Teeffelen and Ariel Amir, Mechanical strain sensing implicated in cell shape recovery in Escherichia coli, Nature Microbiology 2, 17115 (2017), cover article.
  • Felix Wong and Ariel Amir, Mechanics and dynamics of bacterial cell lysis, Biophysical Journal 116, 2378 (2019), cover article.
  • Saman Hussain, …, Ariel Amir, MreB filaments align along greatest principal membrane curvature to orient cell wall synthesis, eLife 7, e32471 (2018).
  • Felix Wong, Ethan C. Garner and Ariel Amir, Mechanics and dynamics of translocating MreB filaments on curved membranes, eLife 8, e40472 (2019).
  • Felix Wong, Samuel Wilson, Rebecca Helbig, Shashi Hegde, Olesia Aftenieva, Hai Zheng, Chenli Liu, Tomáš Pilizota, Ethan C. Garner, Ariel Amir and Lars D. Renner, Understanding beta-lactam-induced lysis at the single-cell level, Frontiers in Microbiology 12, 712007 (2021).
  • Luyi Qiu, John W. Hutchinson and Ariel Amir, Bending instability of rod-shaped bacteria, Physical Review Letters 128, 058101 (2022).
  • Carlos L. Pastrana, Liang Qiu, Shira Armon, Ulrich Gerland and Ariel Amir, Pressure-induced shape-shifting of helical bacteria, Soft Matter 19, 2224–2230 (2023).
  • Carlos L. Pastrana, Liang Qiu, John W. Hutchinson, Ariel Amir and Ulrich Gerland, Mechanics and wrinkling patterns of pressurized bent tubes, Physical Review E 111, L013502 (2025).