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Production, Crystallization, and Structure Determination of the IKK-binding Domain of NEMO
Published on: December 28, 2019
Dimeric structure of the cell shape protein MreC and its functional implications
Fusinita van den Ent1, Mark Leaver, Felipe Bendezu
1MRC-LMB, Hills Road, Cambridge CB2 2QH, UK. fent@mrclmb.cam.ac.uk
Molecular Microbiology
|April 12, 2007
Summary
The bacterial MreC protein
Area of Science:
- Microbiology
- Structural Biology
- Biochemistry
Background:
- MreB protein forms helical filaments in bacteria, maintaining cell shape.
- MreC is co-transcribed with MreB and also forms helical patterns.
- MreC is a bitopic membrane protein with a significant periplasmic domain.
Purpose of the Study:
- To determine the structure of the periplasmic part of MreC from Listeria monocytogenes.
- To investigate the function of MreC in bacterial cell shape maintenance and peptidoglycan synthesis.
- To identify MreC's interaction partners within the cell wall synthesis machinery.
Main Methods:
- X-ray crystallography at 2.5 A resolution to determine MreC structure.
- Site-directed mutagenesis to assess the role of specific MreC domains.
- Bacterial two-hybrid assays to identify MreC's protein interaction partners.
- Deletion analyses to map domain requirements for MreC interactions.
Main Results:
- The structure of the MreC periplasmic domain revealed a dimeric form stabilized by an N-terminal alpha-helix and two C-terminal beta-domains.
- A conserved Thr-Ser dipeptide in one beta-domain was found to be dispensable for cell shape and viability in E. coli and B. subtilis.
- MreC was shown to interact with high-molecular-weight penicillin-binding proteins (PBPs), suggesting a scaffolding role.
- Specific domains of MreC were identified as necessary for interaction with MreD and PBPs.
Conclusions:
- MreC functions as a structural scaffold, organizing peptidoglycan synthesis by recruiting high-molecular-weight PBPs.
- The conserved dipeptide in MreC is not essential for its primary role in cell shape maintenance.
- Understanding MreC structure and interactions provides insights into bacterial cell wall synthesis regulation.
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