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Antimicrobial Peptides Produced by Selective Pressure Incorporation of Non-canonical Amino Acids
Published on: May 4, 2018
Natriuretic peptides modify Pseudomonas fluorescens cytotoxicity by regulating cyclic nucleotides and modifying LPS
Wilfried Veron1, Nicole Orange, Marc Gj Feuilloley
1Laboratory of Cold Microbiology, UPRES EA 2123, University of Rouen, 55 rue Saint Germain, 27000 Evreux, France. wilfried.veron@etu.univ-rouen.fr
BMC Microbiology
|July 11, 2008
Summary
Pseudomonas fluorescens alters its virulence in response to natriuretic peptides like Brain Natriuretic Peptide (BNP) and C-type Natriuretic Peptide (CNP). These peptides influence bacterial cytotoxicity by modulating cyclic nucleotide levels and lipopolysaccharide structure.
Area of Science:
- Microbiology
- Molecular Biology
- Biochemistry
Background:
- Nervous tissues produce natriuretic peptides (BNP, CNP) with structural similarities to cyclic antibacterial peptides.
- Pseudomonas fluorescens, a psychrotrophic bacterium, can induce apoptosis in neurons and glial cells, which are producers of natriuretic peptides.
Purpose of the Study:
- To investigate the sensitivity of Pseudomonas fluorescens to natriuretic peptides.
- To evaluate the distribution and variability of potential natriuretic peptide-dependent sensor systems in the Pseudomonas genus.
Main Methods:
- Assessing the effect of BNP and CNP on P. fluorescens growth and cytotoxicity.
- Measuring intra-bacterial cyclic AMP (cAMP) and cyclic GMP (cGMP) concentrations.
- Analyzing lipopolysaccharide (LPS) structure and activity using capillary electrophoresis.
Main Results:
- BNP and CNP did not affect P. fluorescens growth but altered its cytotoxicity towards glial cells, decreasing apoptosis and increasing necrosis.
- BNP increased intracellular cAMP levels, while CNP increased cGMP levels in P. fluorescens.
- Pre-treatment with BNP or CNP, and specifically cAMP analogues, modified LPS structure and enhanced necrotic activity.
Conclusions:
- P. fluorescens possesses a sensor system responsive to natriuretic peptides, likely coupled to a cyclase.
- This system influences bacterial virulence by potentially affecting LPS synthesis.
- Natriuretic peptides represent a novel regulatory mechanism for Pseudomonas virulence.
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