NKCS, a Mutant of the NK-2 Peptide, Causes Severe Distortions and Perforations in Bacterial, But Not Human Model Lipid Membranes.
NKCS is an improved mutant of the bioactive peptide NK-2, which shows strong activity against Escherichia coli and low toxicity towards human cells. The different activity demonstrates the relevance of the physico-chemical nature of the target membrane for the biological effect of this peptide. We studied the effect of this potent antimicrobial peptide on model membranes by activity studies, differential scanning calorimetry, single molecule tracking and tracer efflux experiments. We found that NKCS severely distorted, penetrated and perforated model lipid membranes that resembled bacterial membranes, but not those that were similar to human cell membranes. The interactions of NKCS with phosphatidylethanolamine, which is abundant in bacterial membranes, were especially strong and are probably responsible for its antimicrobial activity.
Institute for Physical and Theoretical Chemistry, Rheinische Friedrich-Wilhelms-University Bonn, Wegeler Str. 12, 53115 Bonn, Germany. vasilica.ciobanasu@uaic.ro.|Department of Interdisciplinary Research, Alexandru I. Cuza University, Blvd. Carol I, no. 11, Iaşi RO-700506, Romania. vasilica.ciobanasu@uaic.ro.
Corina
C
Ciobanasu
Department of Structural Research on Macromolecules, Institute of Materials Research, Helmholtz-Zentrum Geesthacht, Max-Planck-Str. 1, 21502 Geesthacht, Germany. Agnieszka.Rzeszutek@hzg.de.
Agnieszka
A
Rzeszutek
Institute for Physical and Theoretical Chemistry, Rheinische Friedrich-Wilhelms-University Bonn, Wegeler Str. 12, 53115 Bonn, Germany. u.kubitscheck@uni-bonn.de.
Ulrich
U
Kubitscheck
Department of Structural Research on Macromolecules, Institute of Materials Research, Helmholtz-Zentrum Geesthacht, Max-Planck-Str. 1, 21502 Geesthacht, Germany. regine.willumeit@hzg.de.
Regine
R
Willumeit
D023181:Antimicrobial Cationic Peptides / Q000737:chemistry / Q000494:pharmacology*; D002152:Calorimetry, Differential Scanning; D002462:Cell Membrane / Q000737:chemistry / Q000187:drug effects*; D002942:Circular Dichroism; D004912:Erythrocytes / Q000187:drug effects; D004926:Escherichia coli / Q000187:drug effects*; D006801:Humans; D008563:Membrane Lipids / Q000737:chemistry*; D008567:Membranes, Artificial; D010455:Peptides / Q000737:chemistry; D010713:Phosphatidylcholines; D010714:Phosphatidylethanolamines; D010715:Phosphatidylglycerols
D023181:Antimicrobial Cationic Peptides; D008563:Membrane Lipids; D008567:Membranes, Artificial; D010455:Peptides; D010713:Phosphatidylcholines; D010714:Phosphatidylethanolamines; D010715:Phosphatidylglycerols; C475945:peptide NK-2; C483858:phosphatidylethanolamine