8C0J

Structure of AmiB enzymatic domain bound to the EnvC LytM domain

Summary for 8C0J

• Entry DOI: 10.2210/pdb8c0j/pdb
• Descriptor: N-acetylmuramoyl-L-alanine amidase, Murein hydrolase activator EnvC, ZINC ION, ... (4 entities in total)
• Functional Keywords: complex, hydrolase
• Biological source: Citrobacter rodentium; More
• Total number of polymer chains: 3
• Total formula weight: 67633.27

Authors

Crow, A. (deposition date: 2022-12-17, release date: 2023-06-14, Last modification date: 2024-06-19)

Primary citation

Cook, J.,Baverstock, T.C.,McAndrew, M.B.L.,Roper, D.I.,Stansfeld, P.J.,Crow, A.
Activator-induced conformational changes regulate division-associated peptidoglycan amidases.
Proc.Natl.Acad.Sci.USA, 120:e2302580120-e2302580120, 2023

PubMed Abstract: AmiA and AmiB are peptidoglycan-hydrolyzing enzymes from  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.

PubMed: 37276423
DOI: 10.1073/pnas.2302580120

Experimental method

X-RAY DIFFRACTION (3.381 Å)