title: Effect of head-to-tail cyclization on conformation of histatin-5.
abstract: Histatin-5 (Hst-5, DSHAKRHHGYKRKFHEKHHSHRGY) is a member of a histidine-rich peptide family secreted by major salivary glands, exhibiting high fungicidal activity against Candida albicans. In the present work, we demonstrate the 3D structure of the head-to-tail cyclic variant of Hst-5 in TFE solution determined using NMR spectroscopy and molecular dynamics simulations. The cyclic histatin-5 reveals a helix-loop-helix motif with α-helices at positions Ala(4)-His(7) and Lys(11)-Ser(20). Both helical segments are arranged relative to each other at an angle of ca. 142°. The head-to-tail cyclization increases amphipathicity of the peptide, this, however, does not affect its antimicrobial potency.
authors.affiliation: Faculty of Chemistry, University of Gdańsk, Wita Stwosza 63, 80-308, Gdansk, Poland.
authors.forename: Emilia
authors.initials: E
authors.lastname: Sikorska
authors.forename: Elżbieta
authors.initials: E
authors.lastname: Kamysz
mesh_terms: D000595:Amino Acid Sequence; D003500:Cyclization; D054808:Histatins / Q000737:chemistry*; D056004:Molecular Dynamics Simulation; D008969:Molecular Sequence Data; D019906:Nuclear Magnetic Resonance, Biomolecular; D011487:Protein Conformation
chemical_list: C068075:HTN3 protein, human; D054808:Histatins
keywords: NMR; antimicrobial peptide; head-to-tail cyclization; histatin-5; molecular dynamics simulations