Insights into bacterial cell division from a structure of EnvC bound to the FtsX periplasmic domain

DOI: 10.1073/pnas.2017134117

Authors: Jonathan Cook (University of Warwick) , Tyler C. Baverstock (University of Warwick) , Martin B. L. Mcandrew (University of Warwick) , Phillip J. Stansfeld (University of Warwick) , David I. Roper (University of Warwick) , Allister Crow (University of Warwick)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Proceedings Of The National Academy Of Sciences , VOL 2

State: Published (Approved)
Published: October 2020
Diamond Proposal Number(s): 19880

Abstract: FtsEX is a bacterial ABC transporter that regulates the activity of periplasmic peptidoglycan amidases via its interaction with the murein hydrolase activator, EnvC. In Escherichia coli, FtsEX is required to separate daughter cells after cell division and for viability in low-osmolarity media. Both the ATPase activity of FtsEX and its periplasmic interaction with EnvC are required for amidase activation, but the process itself is poorly understood. Here we present the 2.1 Å structure of the FtsX periplasmic domain in complex with its periplasmic partner, EnvC. The EnvC-FtsX periplasmic domain complex has a 1-to-2 stoichiometry with two distinct FtsX-binding sites located within an antiparallel coiled coil domain of EnvC. Residues involved in amidase activation map to a previously identified groove in the EnvC LytM domain that is here found to be occluded by a “restraining arm” suggesting a self-inhibition mechanism. Mutational analysis, combined with bacterial two-hybrid screens and in vivo functional assays, verifies the FtsEX residues required for EnvC binding and experimentally test a proposed mechanism for amidase activation. We also define a predicted link between FtsEX and integrity of the outer membrane. Both the ATPase activity of FtsEX and its periplasmic interaction with EnvC are required for resistance to membrane-attacking antibiotics and detergents to which E. coli would usually be considered intrinsically resistant. These structural and functional data provide compelling mechanistic insight into FtsEX-mediated regulation of EnvC and its downstream control of periplasmic peptidoglycan amidases.

Journal Keywords: bacterial cell division; peptidoglycan; ABC transporters; X-ray crystallography

Diamond Keywords: Bacteria

Subject Areas: Biology and Bio-materials, Chemistry


Instruments: I04-1-Macromolecular Crystallography (fixed wavelength)

Added On: 04/11/2020 08:35

Documents:
2017134117.full.pdf

Discipline Tags:

Biochemistry Chemistry Structural biology Life Sciences & Biotech

Technical Tags:

Diffraction Macromolecular Crystallography (MX)