Tol Energy-Driven Localization of Pal and Anchoring to the Peptidoglycan Promote Outer-Membrane Constriction

Melissa Petiti (1) , Bastien Serrano (2) , Laura Faure , Roland Lloubes (1) , Tam Mignot (2) , Denis Duché (1, 3)

1 LISM - Laboratoire d'ingénierie des systèmes macromoléculaires
2 LCB - Laboratoire de chimie bactérienne
3 IMM - Institut de Microbiologie de la Méditerranée

During cell division, gram-negative bacteria must coordinate inner-membrane invagination, peptidoglycan synthesis and cleavage and outer-membrane (OM) constriction. The OM constriction remains largely enigmatic, and the nature of this process, passive or active, is under debate. The proton-motive force-dependent Tol-Pal system performs a network of interactions within these three compartments. Here we confirm that the trans-envelope Tol-Pal complex accumulates at constriction site in Escherichia coli. We show that the inner-membrane complex composed of TolA, TolQ and TolR recruits the OM complex TolB-Pal to the septum, in an energy-dependent process. Pal recruitment then allows its binding to peptidoglycan and subsequently OM constriction. Our results provide evidence that the constriction of the OM is an energized process.

Mots clés: OM invagination; Tol–Pal system; membrane vesicles; molecular motor; septum

Domaines: Biochimie, Biologie Moléculaire; Microbiologie et Parasitologie

Melissa Petiti, Bastien Serrano, Laura Faure, Roland Lloubes, Tam Mignot, et al.. Tol Energy-Driven Localization of Pal and Anchoring to the Peptidoglycan Promote Outer-Membrane Constriction. Journal of Molecular Biology, 2019, 431 (17), pp.3275-3288. ⟨10.1016/j.jmb.2019.05.039⟩. ⟨hal-02441016⟩