一种筛选血管紧张素转换酶抑制肽的方法  

A Method for Screening Angiotensin I Converting Enzyme Inhibitory Peptides

作　　者：金清[1] 吴建平 张贵川[3] 邓亚飞[4] 袁吕江[1] 

机构地区：[1]西南大学发光与实时分析教育部重点实验室,重庆400715 [2]Department of Human Ecology,University of Manitoba [3]西南大学食品科学学院,重庆400716 [4]西南大学药学院,重庆400716

出　　处：《食品科学》2011年第19期120-124,共5页Food Science

基　　金：重庆自然科学基金项目(2007BB0345)

摘　　要：实验建立一种从蛋白水解物中快速高效鉴别血管紧张素转化酶抑制剂(ACEI)的方法:先对蛋白按照酶解位点进行序列搜寻,建立一个样品肽库;在量效结构关系(QSAR)研究的基础上对样品库中的肽的ACE抑制活性进行预测,然后化学合成目标肽及测定活性;必要时用现代分析技术确证蛋白水解物中目标肽的存在。用此方法对油菜、大米、小麦蛋白水解物中三肽ACE抑制活性进行研究,发现IC50在10μmol/L以下的三肽多达34条,选择了11条活性较高的肽合成验证,最后发现潜藏在油菜Cruciferin BNC1(P33523)蛋白序列347～349的LRL活性最高,IC50达到3.42μmol/L,且具有较好的稳定性。抑制动力学研究表明,LRL属于竞争性抑制剂;油菜蛋白胃蛋白酶水解物进行分子质量分段,取分子质量小于1000D部分进行高效液相色谱(HPLC)分析发现有LRL。A rapid and highly efficient method for identifying angiotensin I converting enzyme inhibitory peptides from protein hydrolysates was established based on quantitative structure activity relationship（QSAR） and protein sequence.First,a small peptide library was constructed by protein sequence searching according to the hydrolysis sites of a specific enzyme.Then,the activities of peptides in the library were predicted using QSAR model.Target peptides were synthesized and their IC50 values were measured.Finally,a real protein hydrolysate was prepared and HPLC was employed to analyze the target peptides in the hydrolysates.Totally 34 tripeptides with an IC50 of less than 10 μmol/L were predicted from rapeseed protein,wheat protein and rice protein and 11of them with higher activity were synthesized.LRL with the lowest IC50 of 3.42μmol/L located in rapeseed cruciferin BNC1（P33523） sequence 347—349 was characterized from the synthesized peptides.

关 键 词：血管紧张素转换酶抑制剂 QSAR 活性预测 油菜籽蛋白 大米蛋白 小麦蛋白 

分 类 号：TS22[轻工技术与工程—粮食、油脂及植物蛋白工程]