A synthetic peptide corresponding to the C-terminal 25 residues of phage MS2 coded lysis protein dissipates the protonmotive force in Escherichia coli membrane vesicles by generating hydrophilic pores.
The RNA phage MS2 encodes a protein, 75 amino acids long, that is necessary and sufficient for lysis of the host cell. DNA deletion analysis has shown that the lytic activity is confined to the C-terminal half of the protein. We have examined the effects of a synthetic peptide, covering the C-terminal 25 amino acids of the lysis protein, on the electrochemical potential, generated in Escherichia coli membrane vesicles and in liposomes reconstituted with cytochrome c oxidase. In all cases the peptide dissipates the electrochemical potential. The peptide also induces the release of carboxyfluorescein (376 daltons), but not of inuline (5500 daltons), from protein-free liposomes. The phenomena are observed at a lipid to peptide molar ratio of approximately 100:1. The possible connection between the dissipation of the proton-motive force and bacteriolysis is discussed.
Goessens
W H
WH
Department of Biochemistry, University of Leiden, The Netherlands.
Driessen
A J
AJ
Wilschut
J
J
van Duin
J
J
D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000138:chemical synthesis* / Q000494:pharmacology; D002463:Cell Membrane Permeability / Q000187:drug effects*; D004926:Escherichia coli; D008081:Liposomes; D011522:Protons; D012317:RNA Phages / Q000378:metabolism*; D014764:Viral Proteins
D001426:Bacterial Proteins; C029555:E protein, bacteriophage X174; D008081:Liposomes; D011522:Protons; D014764:Viral Proteins