两条鲢鱼小清蛋白源抗冻肽的活性及作用机制比较  

Comparison of the activities and cryoprotective mechanism of two antifreeze peptides derived from silver carp parvalbumin

作　　者：李军[1,2] 符禹婷 俞健 李向红[1,2] 刘永乐 王发祥[1,2] LI Jun;FU Yuting;YU Jian;LI Xianghong;LIU Yongle;WANG Faxiang(College of Food and Bioengineering,Changsha University of Science and Technology,Changsha,Hunan 410114,China;Hunan Provincial Engineering Technology Research Center of Aquatic Food Resources Processing,Changsha,Hunan 410114,China)

机构地区：[1]长沙理工大学食品与生物工程学院,湖南长沙410114 [2]湖南省水生资源食品加工工程技术研究中心,湖南长沙410114

出　　处：《食品与机械》2024年第4期7-12,58,共7页Food and Machinery

基　　金：国家自然科学基金面上项目(编号:32372371);湖南省重点研发计划项目(编号:2022NK2038)。

摘　　要：目的:探讨鲢鱼小清蛋白源抗冻肽的作用机制和构效关系。方法:采用差示扫描量热和分子动力学模拟方法对比分析了两条鲢鱼小清蛋白源抗冻肽的活性、结构及其作用模式。结果:Pv-AFP 1(KAADSFNHKAFFAKVG)呈稳定的α-螺旋结构,而Pv-AFP 2(KAADSFNHKAF)倾向于呈无规卷曲;Pv-AFP 1的热滞值为0.87℃,总平均亲水性为-0.21,热滞活性和两亲性均优于Pv-AFP 2(0.74℃,-0.71);分子动力学模拟显示Pv-AFP 1能结合53个水分子,可形成16个氢键吸附至冰晶表面,结合能为-1514 kJ/mol,均大于Pv-AFP 2(能结合50个水分子,通过形成11个氢键吸附至冰面,结合能为-805 kJ/mol);尽管两条肽序列相似,但其与水分子和冰晶相互作用的主要位点和模式也有一定差异。此外,两条肽均能与冰水界面相互作用,改变了冰面的曲率从而抑制了水的结冰,但Pv-AFP 1抑制冰面生长的效果优于Pv-AFP 2,与热滞活性结果一致。结论:鲢鱼小清蛋白源抗冻肽的活性可能与构象、两亲性及其与水分子和冰晶相互作用的亲和力、位点和模式有关。Objective:Explore the cryoprotective mechanism and structure-activity relationship of antifreeze peptides derived from silver carp parvalbumin.Methods:Using differential scanning calorimetry and molecular dynamics simulation to compare activity,structure and mode of action of two typical peptides.Results:Pv-AFP 1(KAADSFNH KAFFAKVG)had a stableα-helix structure,while Pv-AFP 2(KAADSFNHKAF)tended to exhibit random coil.The thermal hysteresis activity of Pv-AFP 1 was 0.87℃,which was higher than Pv-AFP 2(0.74℃).Molecular dynamics simulations showed that Pv-AFP 1 could interact with 53 water molecules,and could form 16 hydrogen bonds to adsorb onto the surface of ice crystals,with a binding energy of-1514 kJ/mol,all were greater than Pv-AFP 2(can bind 50 water molecules,adsorb on ice surface by forming 11 hydrogen bonds,with a binding energy of-805 kJ/mol).Despite the similarity of the two peptide sequences,their major sites and modes of interactions with water molecules and ice crystals were somewhat different.In addition,both peptides could interact with ice/water interface and altered the curvature of the ice surface,thereby inhibiting water freezing.But Pv-AFP 1 showed a better inhibitory effect on ice surface growth than Pv-AFP 2,which was consistent with their thermal hysteresis activity.Conclusion:The activities of antifreeze peptides derived from silver carp parvalbumin might be related to their structural characters and their affinities,sites and modes of interaction with water molecules and ice crystals.

关 键 词：鲢鱼 小清蛋白 抗冻肽 热滞活性 分子动力学 

分 类 号：TS254.1[轻工技术与工程—水产品加工及贮藏工程]