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Staphylococcus aureus cell growth and division are regulated by an amidase that trims peptides from uncrosslinked peptidoglycan.
- Source :
-
Nature microbiology [Nat Microbiol] 2020 Feb; Vol. 5 (2), pp. 291-303. Date of Electronic Publication: 2020 Jan 13. - Publication Year :
- 2020
-
Abstract
- Bacteria are protected by a polymer of peptidoglycan that serves as an exoskeleton <superscript>1</superscript> . In Staphylococcus aureus, the peptidoglycan assembly enzymes relocate during the cell cycle from the periphery, where they are active during growth, to the division site where they build the partition between daughter cells <superscript>2-4</superscript> . But how peptidoglycan synthesis is regulated throughout the cell cycle is poorly understood <superscript>5,6</superscript> . Here, we used a transposon screen to identify a membrane protein complex that spatially regulates S. aureus peptidoglycan synthesis. This complex consists of an amidase that removes stem peptides from uncrosslinked peptidoglycan and a partner protein that controls its activity. Amidases typically hydrolyse crosslinked peptidoglycan between daughter cells so that they can separate <superscript>7</superscript> . However, this amidase controls cell growth. In its absence, peptidoglycan synthesis becomes spatially dysregulated, which causes cells to grow so large that cell division is defective. We show that the cell growth and division defects due to loss of this amidase can be mitigated by attenuating the polymerase activity of the major S. aureus peptidoglycan synthase. Our findings lead to a model wherein the amidase complex regulates the density of peptidoglycan assembly sites to control peptidoglycan synthase activity at a given subcellular location. Removal of stem peptides from peptidoglycan at the cell periphery promotes peptidoglycan synthase relocation to midcell during cell division. This mechanism ensures that cell expansion is properly coordinated with cell division.
- Subjects :
- Bacterial Proteins genetics
Cell Cycle
Cell Division
Gene Deletion
Genes, Bacterial
Models, Biological
Mutation
N-Acetylmuramoyl-L-alanine Amidase genetics
Peptidoglycan chemistry
Recombinant Proteins genetics
Recombinant Proteins metabolism
Staphylococcus aureus cytology
Staphylococcus aureus genetics
Substrate Specificity
Bacterial Proteins metabolism
N-Acetylmuramoyl-L-alanine Amidase metabolism
Peptidoglycan metabolism
Staphylococcus aureus metabolism
Subjects
Details
- Language :
- English
- ISSN :
- 2058-5276
- Volume :
- 5
- Issue :
- 2
- Database :
- MEDLINE
- Journal :
- Nature microbiology
- Publication Type :
- Academic Journal
- Accession number :
- 31932712
- Full Text :
- https://doi.org/10.1038/s41564-019-0632-1