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Heterogeneous localisation of membrane proteins in Staphylococcus aureus
Felix Weihs1, Katarzyna Wacnik1, Robert D Turner1
1The Krebs Institute. Department of Molecular Biology and Microbiology, University of Sheffield, Firth Court, Western Bank, Sheffield, S10 2TN, UK.
Scientific Reports
|February 28, 2018
Summary
Bacterial membrane proteins, including phospholipid biosynthesis enzymes, show heterogeneous localization in Staphylococcus aureus. This localization is linked to cell division, suggesting new roles for proteins like FtsZ.
Area of Science:
- Microbiology
- Cell Biology
- Biochemistry
Background:
- The bacterial cytoplasmic membrane is crucial for cell function, but protein organization remains poorly understood.
- Previous work indicated heterogeneous localization of phospholipid biosynthetic enzymes (PlsY, CdsA) in Staphylococcus aureus.
Purpose of the Study:
- To investigate the localization patterns of key membrane proteins in Staphylococcus aureus.
- To explore potential functional relationships between membrane proteins, including phospholipid biosynthesis and cell division.
Main Methods:
- Construction and analysis of protein fusions.
- Quantitative image analysis of protein localization.
- Förster Resonance Energy Transfer (FRET) based system to study protein colocalization.
- Inhibition of the cell division protein FtsZ using PC190723.
Main Results:
- Phospholipid biosynthesis enzymes and the lipid raft marker FloT displayed heterogeneous membrane localization.
- The secretion-associated SecY protein showed more homogeneous distribution.
- Novel colocalization was observed between phospholipid biosynthesis enzymes and the respiratory protein CydB.
- PlsY localization was dose-dependent and unaffected by membrane lipid composition.
- Disruption of FtsZ activity led to the loss of PlsY localization.
Conclusions:
- Bacterial membrane protein organization is complex, with enzymes involved in phospholipid biosynthesis exhibiting non-uniform distribution.
- A potential network of interacting membrane proteins, including those involved in respiration and lipid synthesis, has been identified.
- PlsY localization is linked to cell division, suggesting a role for FtsZ beyond septum formation.
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