IDENTIFICATION AND MOLECULAR BASIS FOR EFFICIENT ANTIFREEZE PROTIEN ENHANCERS

描述（由申请人提供）：抗冻蛋白（AFPs）已在许多生物中被发现，如鱼类，植物和昆虫，使它们能够在低于冰点的温度下存活。它们的特点都是能够降低溶液的冰点，而不会明显改变熔点，从而产生热滞后。昆虫的AFPs通常是最活跃的（比I型鱼的AFPs活跃10-100倍）。许多afp的抗冻活性在某些助溶质（称为增强剂）的存在下可以进一步增强。低分子质量化学物质和大分子物质都被认为是蛋白的增强剂，其中一些增强剂确实在生理上增强了蛋白的抗冻活性。据报道，一些增强子可以特异性结合afp。然而，增强效应的机制仍然没有得到很好的描述。加拿大石竹甲虫AFP （DAFP）及其增强因子已被广泛研究。增强剂与AFP的结合已被证明是增强剂增强AFP抗冻活性的一个重要机制。不同AFP系统的增强现象是否有共同的机制？在本项目中，我们将研究一种重要的甲虫AFP系统，来自黄粉虫的粉虫AFP （TmAFP）及其增强子。我们认为增强剂对TmAFP抗冻活性的增强效率取决于增强剂的理化性质。我们将评估所选胺衍生物对TmAFP抗冻活性的增强效率，并将其增强效率与不同的物理化学性质联系起来。我们将确定TmAFP与增强子之间可能的相互作用，并确定TmAFP中参与与增强子结合的关键氨基酸。对AFP和增强剂的研究对于促进我们对生物系统的理解和促进高效AFP系统的开发具有重要意义，这些系统可用于实际的生物医学应用，例如在实验室中低温保存组织和人体健康，以及其他工业应用，如冷冻食品和水合物抑制。本研究将深入了解AFP和AFP增强子的分子机制，并解决关于AFP作用机制的相互矛盾的报道。

DESCRIPTION (provided by applicant): Antifreeze proteins (AFPs) have been identified in a number of organisms, such as fish, plants, and insects, to allow them to survive at subfreezing temperatures. They are all characterized by their ability to depress the freezing point of the solution without appreciably altering the melting point thereby producing a thermal hysteresis. Insect AFPs are often the most active AFPs (10-100 times more active than type I fish AFPs). The antifreeze activities of many AFPs can be further enhanced in the presence of certain co-solutes (called enhancers). Both low molecular mass chemicals and macromolecules have been identified as enhancers for AFPs and some of the enhancers do play a role in enhancing the antifreeze activity of AFPs physiologically. Some of the enhancers have been reported to bind AFPs specifically. The mechanism of the enhancement effect, however, is still poorly described. The AFP from the beetle Dendroides canadensis (DAFP) and the enhancers have been extensively studied. The binding of enhancers to AFP has been demonstrated as one important mechanism for the enhancement effect of enhancers on the antifreeze activity of AFPs. Is there a common mechanism for the enhancement phenomena in different AFP systems? In this project, we will examine an important beetle AFP system, a mealworm AFP from Tenebrio molitor (TmAFP) and the enhancers. We propose that the enhancement efficiency of the enhancers for TmAFP antifreeze activity depends on the physiochemical properties of the enhancers. We will assess the enhancement efficiency of selected amine derivatives on TmAFP antifreeze activity and correlate their enhancement efficiency with their differing physicochemical properties. We will identify the possible interactions between TmAFP and the enhancers and determine the key amino acids in TmAFP involving in binding to the enhancers. The study of AFPs and enhancers is essential to advance our understanding of the biological system and facilitate the development of highly efficient AFP systems for their practical biomedical applications, such as in preservation of tissues at low temperatures in the lab and in human health as well as other industrial applications, such as in frozen foods and in hydrate inhibition. The proposed research will provide insights into the molecular mechanism of AFP and AFP enhancers and resolve conflicting reports regarding the mechanism of action of AFPs.