title: Galleria mellonella native and analogue peptides Gm1 and ΔGm1. II) anti-bacterial and anti-endotoxic effects.
abstract: Antimicrobial peptides (AMPs) are important components of the innate immune system of animals, plants, fungi and bacteria and are recently under discussion as promising alternatives to conventional antibiotics. We have investigated two cecropin-like synthetic peptides, Gm1, which corresponds to the natural overall uncharged Galleria mellonella native peptide and ΔGm1, a modified overall positively charged Gm1 variant. We have analysed these peptides for their potential to inhibit the endotoxin-induced secretion of tumour necrosis factor-α (TNF-α) from human mononuclear cells. Furthermore, in a conventional microbiological assay, the ability of these peptides to inhibit the growth of the rough mutant bacteria Salmonella enterica Minnesota R60 and the polymyxin B-resistant Proteus mirabilis R45 was investigated and atomic force microscopy (AFM) measurements were performed to characterize the morphology of the bacteria treated by the two peptides. We have also studied their cytotoxic properties in a haemolysis assay to clarify potential toxic effects. Our data revealed for both peptides minor anti-inflammatory (anti-endotoxin) activity, but demonstrated antimicrobial activity with differences depending on the endotoxin composition of the respective bacteria. In accordance with the antimicrobial assay, AFM data revealed a stronger morphology change of the R45 bacteria than for the R60. Furthermore, Gm1 had a stronger effect on the bacteria than ΔGm1, leading to a different morphology regarding indentations and coalescing of bacterial structures. The findings verify the biophysical measurements with the peptides on model systems. Both peptides lack any haemolytic activity up to an amount of 100μg/ml, making them suitable as new anti-infective agents.
authors.affiliation: Instituto de Química, Facultad de Ciencias Exactas y Naturales, Universidad de Antioquia, AA. 1226, Medellín, Colombia.. Electronic address: wilcova@gmail.com.
authors.forename: Wilmar
authors.initials: W
authors.lastname: Correa
authors.affiliation: Instituto de Química, Facultad de Ciencias Exactas y Naturales, Universidad de Antioquia, AA. 1226, Medellín, Colombia.. Electronic address: mmanriqm@exactas.udea.edu.co.
authors.forename: Marcela
authors.initials: M
authors.lastname: Manrique-Moreno
authors.affiliation: Forschungszentrum Borstel, Division of Biophysics, Parkallee 10, 23845 Borstel, Germany. Electronic address: jbehrends@fz-borstel.de.
authors.forename: Jochen
authors.initials: J
authors.lastname: Behrends
authors.affiliation: Instituto de Química, Facultad de Ciencias Exactas y Naturales, Universidad de Antioquia, AA. 1226, Medellín, Colombia.. Electronic address: epatino@matematicas.udea.edu.co.
authors.forename: Edwin
authors.initials: E
authors.lastname: Patiño
authors.affiliation: Forschungszentrum Borstel, Division of Biophysics, Parkallee 10, 23845 Borstel, Germany. Electronic address: cmarella@fz-borstel.de.
authors.forename: Chakravarthy
authors.initials: C
authors.lastname: Marella
authors.affiliation: Instituto de Química, Facultad de Ciencias Exactas y Naturales, Universidad de Antioquia, AA. 1226, Medellín, Colombia.. Electronic address: directorgiem@gmail.com.
authors.forename: Carlos
authors.initials: C
authors.lastname: Peláez-Jaramillo
authors.affiliation: Universität Halle-Wiienberg, Institut für Physikalische Chemie, Von-Danckelmann-Platz 4, 06120 Halle/Saale, Germany. Electronic address: Patrick.Garidel@chemie.uni-halle.de.
authors.forename: Patrick
authors.initials: P
authors.lastname: Garidel
authors.affiliation: Forschungszentrum Borstel, Division of Biophysics, Parkallee 10, 23845 Borstel, Germany. Electronic address: tgutsmann@fz-borstel.de.
authors.forename: Thomas
authors.initials: T
authors.lastname: Gutsmann
authors.affiliation: Forschungszentrum Borstel, Division of Biophysics, Parkallee 10, 23845 Borstel, Germany. Electronic address: kbrandenburg@fz-borstel.de.
authors.forename: Klaus
authors.initials: K
authors.lastname: Brandenburg
authors.affiliation: Forschungszentrum Borstel, Division of Biophysics, Parkallee 10, 23845 Borstel, Germany. Electronic address: lheinbockel@fz-borstel.de.
authors.forename: Lena
authors.initials: L
authors.lastname: Heinbockel
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000494:pharmacology; D023181:Antimicrobial Cationic Peptides / Q000737:chemistry / Q000494:pharmacology; D002478:Cells, Cultured; D019446:Endotoxemia / Q000139:chemically induced / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D005260:Female; D006801:Humans; D019476:Insect Proteins / Q000737:chemistry / Q000494:pharmacology; D007963:Leukocytes, Mononuclear / Q000378:metabolism* / Q000473:pathology; D008070:Lipopolysaccharides / Q000633:toxicity; D008297:Male; D009036:Moths / Q000737:chemistry*; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism
chemical_list: D000900:Anti-Bacterial Agents; D023181:Antimicrobial Cationic Peptides; D019476:Insect Proteins; D008070:Lipopolysaccharides; D014409:Tumor Necrosis Factor-alpha
keywords: Antibacterial/antimicrobial peptide; Atomic force microscopy; Galleria mellonella; Lipopolysaccharide; Peptide-lipid interaction