Extracellular Death Factor

Science's STKE  30 Oct 2007:
Vol. 2007, Issue 410, pp. tw395
DOI: 10.1126/stke.4102007tw395

Programmed cell death (PCD) has traditionally been considered to be restricted to eukaryotic multicellular organisms; however, several genetic modules in prokaryotes are known to mediate a type of programmed cell death. In Escherichia coli, mazF encodes a stable toxin, and mazE encodes a labile antitoxin, that prevents the lethal effect of MazF. Kolodkin-Gal et al. (see the Perspective by Kolter) now show that E. coli mazEF-mediated cell death is a population phenomenon that requires a quorum-sensing signal molecule, extracellular death factor (EDF). EDF is a symmetric, linear pentapeptide whose amino acid sequence is Asn-Asn-Trp-Asn-Asn. In synthetic peptides, the symmetrical arrangement of each of the five amino acids of EDF was important for mazEF-mediated killing activity.

I. Kolodkin-Gal, R. Hazan, A. Gaathon, S. Carmeli, H. Engelberg-Kulka, A linear pentapeptide is a quorum-sensing factor required for mazEF-mediated cell death in Escherichia coli. Science 318, 652-655 (2007). [Abstract] [Full Text]

R. Kolter, Deadly priming. Science 318, 578-579 (2007). [Summary] [Full Text]