Dislocation-mediated growth of bacterial cell walls

Abstract

Recent experiments have illuminated a remarkable growth mechanism of rod-shaped bacteria: proteins associated with cell wall extension move at constant velocity in circles oriented approximately along the cell circumference (Garner et al., Science (2011), Dominguez-Escobar et al. Science (2011), van Teeffelen et al. PNAS (2011). We view these as dislocations in the partially ordered peptidoglycan structure, activated by glycan strand extension machinery, and study theoretically the dynamics of these interacting defects on the surface of a cylinder. Generation and motion of these interacting defects lead to surprising effects arising from the cylindrical geometry, with important implications for growth. We also discuss how long range elastic interactions and turgor pressure affect the dynamics of the fraction of actively moving dislocations in the bacterial cell wall.

to appear in PNAS

References in corpus (3)

• Direct measurement of cell wall stress-stiffening and turgor pressure in live bacterial cells
• Submicron plasticity: yield stress, dislocation avalanches, and velocity distribution
• Criticality of relaxation in dislocation systems

Cited by in corpus (20)

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• Bending forces plastically deform growing bacterial cell walls
• Motile dislocations knead odd crystals into whorls
• Universality in stochastic exponential growth
• Defect-Mediated Phase Transitions in Active Soft Matter
• Intergenerational continuity of cell shape dynamics in Caulobacter crescentus
• Getting into shape: how do rod-like bacteria control their geometry?
• Theory of interacting dislocations on cylinders
• Plastic deformation of tubular crystals by dislocation glide
• Simulation and observation of line-slip structures in columnar structures of soft spheres
• Elongation and shape changes in organisms with cell walls: a dialogue between experiments and models
• Theory of rotational columnar structures of soft spheres
• Active topological defect absorption by a curvature singularity
• Dimensional cross-over of hard parallel cylinders confined on cylindrical surfaces
• Transverse Quantum Superfluids
• Gene expression in growing cells: A biophysical primer
• A Geometric Mapping from Rectilinear Material Orthotropy to Isotropy: Insights to Plates and Shells
• Circumferential gap propagation in an anisotropic elastic bacterial sacculus
• Shape-dependent bounds on cell growth rates
• Defect-free and defective adaptations of crystalline sheets to stretching deformation