Aggregation of Antifreeze Protein and Impact on Antifreeze Activity

• Published in: The journal of physical chemistry. B Vol. 110; no. 41; pp. 20562 - 20567
• Main Authors: Du, Ning, Liu, Xiang Y, Hew, Choy L
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 19-10-2006
• Subjects: Antifreeze Proteins, Type III - chemistry; Biophysics - methods; Chemistry, Physical - methods; Ice; Kinetics; Models, Biological; Models, Theoretical; Molecular Conformation; Protein Binding; Protein Conformation; Surface Properties; Temperature; Thermodynamics
• ISSN: 1520-6106; 1520-5207
• DOI: 10.1021/jp061969y

Antifreeze protein type III aggregates once the concentration exceeds a critical value, the so-called critical aggregation concentration (CAC). It was found for the first time that the aggregation of antifreeze protein exerts a direct impact on the antifreeze efficiency. It follows from our measurements that the AFP III above CAC will enhance the antifreeze activity because of the increase of the kink kinetics barrier of surface integration. This is attributed to the optimal packing of AFP III molecules on the surface of the ice nucleus as well as ice crystals above CAC. This study will extend our understanding of the antifreeze mechanism of antifreeze protein monomers as well as antifreeze aggregates on ice nucleation and shed light on the selection of antifreeze agents.