Survival from the Cold Winter: Freezing and Ice Crystallization Inhibition by Antifreeze Proteins

Antifreeze proteins (AFPs), occurring in some polar animals, plants, fungi, and other organisms, are capable of inhibiting ice freezing at subzero temperatures. The application of AFPs can be found in medicine and industry where low temperature storage is required and ice crystallization is damaging. This includes improved protection of blood platelets and human organs at low temperature, increasing the effectiveness of the destruction of malignant tumors in cryosurgery, and improvement of the smooth texture of frozen foods. In this review, the antifreeze mechanisms of AFPs are discussed, focusing on their inhibition effects on both ice nucleation and crystal growth. AFPs have been found to act in two stages. As a precursor to ice growth, ice nucleation is suppressed by the surface adsorption of AFPs to both ice nucleus and ice nucleators. At the second stage, in cases where inhibition of ice nucleation has had partial or no success, AFPs proceed to inhibit the growth of ice by adsorbing on specific surfaces of ice. Based The authors Ning Du, Guoyang William Toh, contributed equally to this work. N. Du Department of Physics and Department of Chemistry, Faculty of Science, National University of Singapore, 2 Science Drive 3, 117542, Singapore Singapore-MIT Alliance for Research and Technology Center, Block S16, 3 Science Drive 2, Singapore, 117543 Singapore G.W. Toh Department of Physics and Department of Chemistry, Faculty of Science, National University of Singapore, 2 Science Drive 3, 117542, Singapore X.Y. Liu ( ) College of Materials, Xiamen University, 422 Si Ming Nan Road, Xiamen, 361005, P.R. China Department of Physics and Department of Chemistry, Faculty of Science, National University of Singapore, 2 Science Drive 3, 117542, Singapore e-mail: [email protected] X.Y. Liu (ed.), Bioinspiration: From Nano to Micro Scales, Biological and Medical Physics, Biomedical Engineering, DOI 10.1007/978-1-4614-5372-7 2, © Springer ScienceCBusiness Media New York 2012 57