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.
Ice-binding structure and mechanism of an antifreeze protein from winter flounder.,Sicheri F, Yang DS Nature. 1995 Jun 1;375(6530):427-31. PMID:7760940[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
↑ Sicheri F, Yang DS. Ice-binding structure and mechanism of an antifreeze protein from winter flounder. Nature. 1995 Jun 1;375(6530):427-31. PMID:7760940 doi:http://dx.doi.org/10.1038/375427a0