Signal peptide of the colicin E2 lysis protein causes host cell death.
Colicin E2 is encoded by the SOS-inducible colicin operon of plasmid ColE2-P9. Highly induced colicin E2 is excreted from the E. coli host cell, accompanied by quasi-lysis and cell death. These three events are all directed by the colicin lysis protein that comprises the signal peptide and a small mature lipoprotein. We constructed a mutant lysis gene encoding its complete signal peptide with addition of two external amino acids at the C-terminus. By using this mutant peptide as a reference, the wild type lysis signal peptide was identified and shown to remain quite stable after the cleavage. This mutant peptide also mimics the cleaved-off signal peptide avoiding the influence of the mature lysis lipoprotein, and suggested that cell death by the lysis protein, but neither colicin excretion nor quasi-lysis, is decided by the nature of its signal region.
Department of Biotechnology, Faculty of Agriculture, University of Tokyo, Japan.
S
S
Kanoh
H
H
Masaki
S
S
Yajima
T
T
Ohta
T
T
Uozumi
D001483:Base Sequence; D002470:Cell Survival / Q000502:physiology; D003087:Colicins / Q000493:pharmacokinetics*; D008969:Molecular Sequence Data; D010957:Plasmids; D021382:Protein Sorting Signals / Q000235:genetics / Q000502:physiology*
D003087:Colicins; D021382:Protein Sorting Signals