title: Analysis of calcium-induced effects on the conformation of fengycin.
abstract: Fengycin is a natural lipopeptide with antifungal and eliciting properties and able to inhibit the activity of phospholipase A2. A combination of CD, FT-IR, NMR and fluorescence spectroscopic techniques was applied to elucidate its conformation in a membrane-mimicking environment and to investigate the effect of calcium ions on it. We mainly observed that fengycin adopts a turn conformation. Our results showed that calcium ions are bound by the two charged glutamates. The calcium binding has an influence on the fengycin conformation and more particularly, on the environment of the tyrosine residues. The modulation of the fengycin conformation by the environmental conditions may influence its biological properties.
authors.affiliation: Unité de Chimie biologique industrielle, University of Liege, Passage des Déportés, 2, 5030 Gembloux, Belgium.
authors.forename: Mehmet Nail
authors.initials: MN
authors.lastname: Nasir
authors.forename: Pascal
authors.initials: P
authors.lastname: Laurent
authors.forename: Christelle
authors.initials: C
authors.lastname: Flore
authors.forename: Laurence
authors.initials: L
authors.lastname: Lins
authors.forename: Marc
authors.initials: M
authors.lastname: Ongena
authors.forename: Magali
authors.initials: M
authors.lastname: Deleu
mesh_terms: D000595:Amino Acid Sequence; D000935:Antifungal Agents / Q000737:chemistry* / Q000378:metabolism; D001412:Bacillus subtilis / Q000737:chemistry* / Q000378:metabolism; D001665:Binding Sites; D002118:Calcium / Q000737:chemistry* / Q000378:metabolism; D002942:Circular Dichroism; D055666:Lipopeptides / Q000737:chemistry* / Q000378:metabolism; D019906:Nuclear Magnetic Resonance, Biomolecular; D017433:Protein Structure, Secondary; D013050:Spectrometry, Fluorescence; D017550:Spectroscopy, Fourier Transform Infrared
chemical_list: D000935:Antifungal Agents; D055666:Lipopeptides; C049972:fengycin; D002118:Calcium