title: Ice-binding structure and mechanism of an antifreeze protein from winter flounder.
abstract: Antifreeze proteins provide fish with protection against the freezing effect of polar environments by binding to ice surfaces and inhibiting growth of ice crystals. We present the X-ray crystal structure at 1.5 A resolution of a lone alpha-helical antifreeze protein from winter flounder, which provides a detailed look at its ice-binding features. These consist of four repeated ice-binding motifs, the side chains of which are inherently rigid or restrained by pair-wise side-chain interactions to form a flat binding surface. Elaborate amino- and carboxy-terminal cap structures are also present, which explain the protein's rich alpha-helical content in solution. We propose an ice-binding model that accounts for the binding specificity of the antifreeze protein along the <0112> axes of the (2021) ice planes.
authors.affiliation: Department of Biochemistry, Faculty of Health Science, McMaster University, Hamilton, Ontario, Canada.
authors.forename: F
authors.initials: F
authors.lastname: Sicheri
authors.forename: D S
authors.initials: DS
authors.lastname: Yang
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D021301:Antifreeze Proteins; D003196:Computer Graphics; D018360:Crystallography, X-Ray; D005432:Flounder; D006023:Glycoproteins / Q000737:chemistry*; D007053:Ice; D008969:Molecular Sequence Data; D011485:Protein Binding; D011487:Protein Conformation
chemical_list: D021301:Antifreeze Proteins; D006023:Glycoproteins; D007053:Ice