Activator-induced conformational changes regulate division-associated peptidoglycan amidases

DOI: 10.1073/pnas.2302580120

Authors: Jonathan Cook (University of Warwick) , Tyler C. Baverstock (University of Warwick) , Martin b. L. Mcandrew (University of Warwick) , David I. Roper (University of Warwick) , Phillip j. Stansfeld (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 120

State: Published (Approved)
Published: June 2023
Diamond Proposal Number(s): 26803 , 25402

Abstract: AmiA and AmiB are peptidoglycan-hydrolyzing enzymes from Escherichia coli that are required to break the peptidoglycan layer during bacterial cell division and maintain integrity of the cell envelope. In vivo, the activity of AmiA and AmiB is tightly controlled through their interactions with the membrane-bound FtsEX–EnvC complex. Activation of AmiA and AmiB requires access to a groove in the amidase-activating LytM domain of EnvC which is gated by ATP-driven conformational changes in FtsEX–EnvC complex. Here, we present a high-resolution structure of the isolated AmiA protein, confirming that it is autoinhibited in the same manner as AmiB and AmiC, and a complex of the AmiB enzymatic domain bound to the activating EnvC LytM domain. In isolation, the active site of AmiA is blocked by an autoinhibitory helix that binds directly to the catalytic zinc and fills the volume expected to accommodate peptidoglycan binding. In the complex, binding of the EnvC LytM domain induces a conformational change that displaces the amidase autoinhibitory helix and reorganizes the active site for activity. Our structures, together with complementary mutagenesis work, defines the conformational changes required to activate AmiA and/or AmiB through their interaction with their cognate activator EnvC.

Journal Keywords: bacterial cell division; X-ray crystallography; peptidoglycan; structural microbiology; Amidases

Diamond Keywords: Enzymes

Subject Areas: Biology and Bio-materials


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

Added On: 14/06/2023 11:42

Documents:
pnas.2302580120.pdf

Discipline Tags:

Structural biology Life Sciences & Biotech

Technical Tags:

Diffraction Macromolecular Crystallography (MX)