The transpeptidase PBP2 governs initial localization and activity of the major cell-wall synthesis machinery in E. coli

Gizem Özbaykal (1, 2) , Eva Wollrab (1) , François Simon (1) , Antoine Vigouroux (3, 1, 4) , Baptiste Cordier (1) , Andrey Aristov (1) , Thibault Chaze (5) , Mariette Matondo (5) , Sven van Teeffelen (1)

1 Morphogénèse et Croissance microbiennes / Microbial Morphogenesis and Growth
2 Université Paris Diderot, Sorbonne Paris Cité, Paris, France
3 Biologie de Synthèse - Synthetic biology
4 Université Paris-Descartes, Sorbonne Paris Cité, 75014 Paris, France
5 UTechS MSBio - Spectrométrie de Masse pour la Biologie – Mass Spectrometry for Biology

Bacterial shape is physically determined by the peptidoglycan cell wall. The cell-wall-synthesis machinery responsible for rod shape in Escherichia coli is the processive 'Rod complex'. Previously, cytoplasmic MreB filaments were thought to govern formation and localization of Rod complexes based on local cell-envelope curvature. Using single-particle tracking of the transpeptidase and Rod-complex component PBP2, we found that PBP2 binds to a substrate different from MreB. Depletion and localization experiments of other putative Rod-complex components provide evidence that none of those provide the sole rate-limiting substrate for PBP2 binding. Consistently, we found only weak correlations between MreB and envelope curvature in the cylindrical part of cells. Residual correlations do not require curvature-based Rod-complex initiation but can be attributed to persistent rotational motion. We therefore speculate that the local cell-wall architecture provides the cue for Rod-complex initiation, either through direct binding by PBP2 or through an unknown intermediate.

Mots clés: E. coli; MreB cytoskeleton; Rod complex; bacterial morphogenesis; cell-wall insertion; infectious disease; microbiology; physics of living systems; single-enzyme dynamics

Domaines: Biologie moléculaire; Biochimie, Biologie Moléculaire

Gizem Özbaykal, Eva Wollrab, François Simon, Antoine Vigouroux, Baptiste Cordier, et al.. The transpeptidase PBP2 governs initial localization and activity of the major cell-wall synthesis machinery in E. coli. eLife, 2020, 9, ⟨10.7554/eLife.50629⟩. ⟨pasteur-02572914⟩