title: Carbamylated LL-37 as a modulator of the immune response.
abstract: Carbamylation of lysine residues and protein N-termini is an ubiquitous, non-enzymatic post-translational modification. Carbamylation at sites of inflammation is due to cyanate formation during the neutrophil oxidative burst and may target lysine residues within the antimicrobial peptide LL-37. The bactericidal and immunomodulatory properties of LL-37 depend on its secondary structure and cationic nature, which are conferred by arginine and lysine residues. Therefore, carbamylation may affect the biological functions of LL-37. The present study examined the kinetics and pattern of LL-37 carbamylation to investigate how this modification affects the bactericidal, cytotoxic and immunomodulatory function of the peptide. The results indicated that LL-37 undergoes rapid modification in the presence of physiological concentrations of cyanate, yielding a spectrum of diverse carbamylated peptides. Mass spectrometry analyses revealed that theN-terminal amino group of Leu-1 was highly reactive and was modified almost instantly by cyanate to generate the predominant form of the modified peptide, named LL-37(C1) This was followed by the sequential carbamylation of Lys-8, Lys-12, and Lys-15 to yield LL-37(C8), and Lys-15 to yield LL-37(C12,15) Carbamylation had profound and diverse effects on the structure and biological properties of LL-37. In some cases, anti-inflammatory LL-37 was rapidly converted to pro-inflammatory LL-37.
authors.affiliation: Broegelmann Research Laboratory, Department of Clinical Science, University of Bergen, Bergen, Norway.
authors.forename: Catalin
authors.initials: C
authors.lastname: Koro
authors.affiliation: Broegelmann Research Laboratory, Department of Clinical Science, University of Bergen, Bergen, Norway Malopolska Centre of Biotechnology, Jagiellonian University, Krakow, Poland.
authors.forename: Annelie
authors.initials: A
authors.lastname: Hellvard
authors.affiliation: Broegelmann Research Laboratory, Department of Clinical Science, University of Bergen, Bergen, Norway.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Delaleu
authors.affiliation: Broegelmann Research Laboratory, Department of Clinical Science, University of Bergen, Bergen, Norway.
authors.forename: Veronika
authors.initials: V
authors.lastname: Binder
authors.affiliation: Interdisciplinary Nanoscience Center at the Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark.
authors.forename: Carsten
authors.initials: C
authors.lastname: Scavenius
authors.affiliation: Broegelmann Research Laboratory, Department of Clinical Science, University of Bergen, Bergen, Norway.
authors.forename: Brith
authors.initials: B
authors.lastname: Bergum
authors.affiliation: Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Krakow, Poland.
authors.forename: Izabela
authors.initials: I
authors.lastname: Główczyk
authors.affiliation: Periodontal Research Group MRC Centre for Immune Regulation, University of Birmingham, Birmingham, UK.
authors.forename: Helen M
authors.initials: HM
authors.lastname: Roberts
authors.affiliation: Periodontal Research Group MRC Centre for Immune Regulation, University of Birmingham, Birmingham, UK.
authors.forename: Iain L C
authors.initials: IL
authors.lastname: Chapple
authors.affiliation: Periodontal Research Group MRC Centre for Immune Regulation, University of Birmingham, Birmingham, UK.
authors.forename: Melissa M
authors.initials: MM
authors.lastname: Grant
authors.affiliation: Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Krakow, Poland.
authors.forename: Maria
authors.initials: M
authors.lastname: Rapala-Kozik
authors.affiliation: Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Krakow, Poland.
authors.forename: Kinga
authors.initials: K
authors.lastname: Klaga
authors.affiliation: Interdisciplinary Nanoscience Center at the Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark.
authors.forename: Jan J
authors.initials: JJ
authors.lastname: Enghild
authors.affiliation: Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Krakow, Poland Department of Oral Immunology and Infectious Diseases, University of Louisville School of Dentistry, Louisville, KY, USA.
authors.forename: Jan
authors.initials: J
authors.lastname: Potempa
authors.affiliation: Broegelmann Research Laboratory, Department of Clinical Science, University of Bergen, Bergen, Norway Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Krakow, Poland piotr.mydel@uib.no.
authors.forename: Piotr
authors.initials: P
authors.lastname: Mydel
mesh_terms: D023181:Antimicrobial Cationic Peptides / Q000737:chemistry / Q000276:immunology / Q000378:metabolism*; D002478:Cells, Cultured; D002633:Chemotaxis / Q000187:drug effects; D003485:Cyanates / Q000737:chemistry / Q000494:pharmacology*; D016207:Cytokines / Q000378:metabolism; D006801:Humans; D056747:Immunomodulation / Q000187:drug effects; D007249:Inflammation / Q000276:immunology*; D008070:Lipopolysaccharides / Q000276:immunology; D008239:Lysine / Q000737:chemistry; D008264:Macrophages / Q000276:immunology* / Q000382:microbiology; D013058:Mass Spectrometry; D009504:Neutrophils / Q000276:immunology*; D018384:Oxidative Stress; D011499:Protein Processing, Post-Translational / Q000187:drug effects; D054804:Cathelicidins
chemical_list: D023181:Antimicrobial Cationic Peptides; D003485:Cyanates; D016207:Cytokines; D008070:Lipopolysaccharides; D008239:Lysine; D054804:Cathelicidins
keywords: Carbamylation; LL-37; immunomodulation