Novel Quorum-Sensing Peptides Mediating Interspecies Bacterial Cell Death

• DOI: 10.1128/mbio.00314-13
• Publication Date: 2013-06-05T00:16:36Z
• Authors: Sathish Kumar; Ilana Kolodkin-Gal; Hanna Engelberg-K...
• Keywords: 0301 basic medicine; 0303 health sciences; Microbial Viability; Escherichia coli Proteins; Quorum Sensing; Microbiology; QR1-502; Culture Media; DNA-Binding Proteins; 03 medical and health sciences; Endoribonucleases; Pseudomonas aeruginosa; Escherichia coli; Oligopeptides; Research Article; Bacillus subtilis

ABSTRACT Escherichia coli mazEF is a toxin-antitoxin stress-induced module mediating cell death. It requires the quorum-sensing signal (QS) "extracellular death factor" (EDF), penta-peptide NNWNN (EcEDF), enhancing endoribonucleolytic activity of E. toxin MazF. Here we discovered that mazEF-mediated could be triggered by QS peptides from supernatants (SN) Gram-positive bacterium Bacillus subtilis and Gram-negative Pseudomonas aeruginosa. In SN B. subtilis, found one EDF, hexapeptide RGQQNE, called BsEDF. P. aeruginosa, three EDFs: nonapeptide INEQTVVTK, PaEDF-1, two hexadecapeptides, VEVSDDGSGGNTSLSQ, PaEDF-2, APKLSDGAAAGYVTKA, PaEDF-3. When added to diluted cultures, each these acted as an interspecies EDF Furthermore, though their sequences are very different, EDFs amplified MazF, probably interacting with different sites on Finally, suggest may become basis for new class antibiotics trigger outside bacterial cells. IMPORTANCE Bacteria communicate another via molecules. provides mechanism bacteria monitor other's presence modulate gene expression in response population density. Previously, peptide NNWNN, this list extended group several additional peptides. The produced other bacteria, Thus, study established "new family EDFs." This first example molecules participating triggering acting cell.