In Vitro Activity and Potency of an Intravenously Injected Antimicrobial Peptide and Its dl Amino Acid Analog in Mice Infected with Bacteria

Abstract
We report that intravenous injection (3 mg/kg of body weight twice daily) of a diastereomer (containing 33% d amino acids) of an antimicrobial peptide, K6L9 (LKLLKKLLKKLLKLL-NH2), but not the all-l-amino-acid parental peptide, cures neutropenic mice infected with gentamicin-sensitive Pseudomonas aeruginosa and gentamicin-resistant Acinetobacter baumannii bacteria. Various biophysical experiments suggest a membranolytic-like effect.