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A Fluorescence-based Method to Study Bacterial Gene Regulation in Infected Tissues
Published on: February 19, 2019
The Enterococcus faecalis exoproteome: identification and temporal regulation by Fsr
Jayendra Shankar1, Rachel G Walker, Deborah Ward
1Institute of Integrative Biology, University of Liverpool, Liverpool, United Kingdom.
Plos One
|March 20, 2012
Summary
The fsrABDC operon integrity dictates Enterococcus faecalis exoproteome composition, distinguishing protease-expressing strains. This finding impacts understanding of bacterial protein secretion and stress responses.
Area of Science:
- Microbiology
- Bacterial Pathogenesis
- Proteomics
Background:
- High-level gentamicin and ciprofloxacin-resistant Enterococcus faecalis clinical isolates from the UK and Ireland were analyzed.
- Two distinct PFGE clusters were identified, suggesting potential differences in virulence or adaptation.
Purpose of the Study:
- To investigate the exoproteome composition of resistant Enterococcus faecalis isolates.
- To determine the role of the fsrABDC operon in regulating exoprotein profiles.
- To identify specific proteins associated with different isolate clusters.
Main Methods:
- Analysis of culture supernatant exoproteins using 2D gel electrophoresis.
- Protein identification via mass spectrometry.
- Genetic manipulation (mutant generation and complementation) of the fsrABDC operon.
Main Results:
- Two distinct exoprotein profiles were observed, correlating with GelE metalloprotease expression and PFGE clusters.
- The fsrABDC operon integrity was identified as the key determinant of exoproteome composition.
- An fsrB mutant exhibited an exoproteome similar to GelE-negative strains, characterized by stress and glycolytic proteins.
Conclusions:
- The fsrABDC operon controls the secretion of key proteases (GelE, SprE) in Enterococcus faecalis.
- Alterations in the fsrABDC operon lead to significant changes in the bacterial exoproteome, potentially affecting virulence and stress adaptation.
- The exoproteome of an fsrB mutant suggests a link between fsr regulation and general stress responses.
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