Magainins and the disruption of membrane-linked free-energy transduction.
Magainins, a family of positively charged peptides, are partly if not wholly responsible for antimicrobial activity in skin extracts of Xenopus laevis. We report here that members of the magainin family--i.e., the 21-amino acid peptide PGLa and the 23-amino acid peptide magainin 2 amide (PGSa)--dissipate the electric potential across various energy-transducing membranes and thus uncouple respiration from other free-energy-requiring processes. We propose that this is a likely mechanism for the antimicrobial effects of these compounds.
Westerhoff
H V
HV
Laboratory of Molecular Biology, National Institute of Diabetes, Digestive, and Kidney Diseases, Bethesda, MD 20892.
Juretić
D
D
Hendler
R W
RW
Zasloff
M
M
D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D023181:Antimicrobial Cationic Peptides; D002259:Carbonyl Cyanide p-Trifluoromethoxyphenylhydrazone / Q000494:pharmacology; D002462:Cell Membrane / Q000187:drug effects / Q000502:physiology*; D004926:Escherichia coli / Q000502:physiology; D054806:Magainins; D008297:Male; D008564:Membrane Potentials / Q000187:drug effects; D008930:Mitochondria, Liver / Q000187:drug effects / Q000378:metabolism*; D010085:Oxidative Phosphorylation / Q000187:drug effects; D010455:Peptides / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains; D029867:Xenopus Proteins; D014982:Xenopus laevis
D000900:Anti-Bacterial Agents; D023181:Antimicrobial Cationic Peptides; D054806:Magainins; D010455:Peptides; D029867:Xenopus Proteins; C045866:peptide-Gly-Leu-amide; C053301:magainin 2 peptide, Xenopus; D002259:Carbonyl Cyanide p-Trifluoromethoxyphenylhydrazone