Postsegregational killing mediated by the P1 phage "addiction module" phd-doc requires the Escherichia coli programmed cell death system mazEF.
"Addiction modules" consist of two genes; the product of the second is long lived and toxic, while the product of the first is short lived and antagonizes the lethal action of the toxin. The extrachromosomal addiction module phd-doc, located on the P1 prophage, is responsible for the postsegregational killing effect (death of plasmid-free cells). The Escherichia coli chromosomal addiction module analogue, mazEF, is responsible for the induction of programmed cell death. Here we show that the postsegregational killing mediated by the P1 phd-doc module depends on the presence of the E. coli mazEF system. In addition, we demonstrate that under conditions of postsegregational killing, mediated by phd-doc, protein synthesis of E. coli is inhibited. Based on our findings, we suggest the existence of a coupling between the phd-doc and mazEF systems.
Department of Molecular Biology, The Hebrew University-Hadassah Medical School, Jerusalem 91120, Israel.
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Hazan
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Reches
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Engelberg-Kulka
D000992:Antitoxins / Q000235:genetics / Q000378:metabolism; D017209:Apoptosis; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D001427:Bacterial Toxins / Q000235:genetics; D017101:Bacteriophage P1 / Q000235:genetics / Q000502:physiology*; D004926:Escherichia coli / Q000235:genetics / Q000254:growth & development / Q000378:metabolism / Q000821:virology*; D010957:Plasmids / Q000235:genetics; D014764:Viral Proteins / Q000235:genetics / Q000378:metabolism*
D000992:Antitoxins; D001426:Bacterial Proteins; D001427:Bacterial Toxins; C083664:Doc protein, Enterobacteria phage P1; C083665:Phd protein, Enterobacteria phage P1; D014764:Viral Proteins