Outer membrane-anchoring enables LpoB to regulate peptidoglycan synthesis rate
Ali A Kermani1, Jacob Biboy1, Daniela Vollmer1
1Centre for Bacterial Cell Biology, Biosciences Institute, Newcastle University, Richardson Road, Newcastle Upon Tyne NE2 4AX, UK.
Cell Surface (Amsterdam, Netherlands)
|October 28, 2022
Summary
Outer membrane anchoring of LpoB is crucial for bacterial cell wall synthesis regulation. Mis-localizing LpoB disrupts cell shape and peptidoglycan production, especially under osmotic stress.
Area of Science:
- Bacterial cell envelope biogenesis
- Molecular microbiology
- Cellular stress response
Background:
- Peptidoglycan (PG) is vital for bacterial cell shape and integrity.
- PG synthesis is regulated by PG synthases and hydrolases.
- Outer membrane (OM)-anchored lipoproteins (LpoA, LpoB) activate PG synthases (PBPs) in *Escherichia coli*.
Purpose of the Study:
- To investigate the role of OM-anchoring in Lpo protein function.
- To determine how Lpo protein mis-localization affects bacterial cell morphology and PG synthesis.
- To understand PG synthesis regulation under environmental stress.
Main Methods:
- Investigated the effects of artificially tethering LpoB to the cytoplasmic membrane (CM).
- Assessed changes in cell morphology and PG synthesis rates.
- Examined bacterial response to high osmolarity growth medium and osmotic upshift.
Main Results:
- Artificially tethering LpoB to the CM altered its function.
- Mis-localized LpoB significantly affected cell growth and morphology in high osmolarity.
- PG synthesis rate was reduced upon osmotic upshift in mis-localized LpoB cells.
Conclusions:
- OM-anchoring of LpoB is essential for proper regulation of PG synthesis.
- Proper localization of Lpo proteins is critical for bacterial adaptation to environmental stresses.
- Disrupting LpoB localization impacts cell envelope integrity and stress response.
Keywords:
Osmotic upshiftOuter membrane lipoproteinsPenicillin-binding proteinPeptidoglycanmis-localized LpoBMore Related Videos
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