大黄鱼蛋白源ACE抑制三肽的虚拟筛选、体外活性验证及分子机制

纪慧卓; 陈嘉钰; 李欣; 马汝平; 于志鹏; 赵文竹; 励建荣

doi:10.13386/j.issn1002-0306.2020060287

大黄鱼蛋白源ACE抑制三肽的虚拟筛选、体外活性验证及分子机制

Screening,in Vitro Activity and Molecular Mechanism of ACE Inhibitory Tirpeptides from Larimichthys crocea Protein

摘要

摘要: 本文利用在线数据库对大黄鱼膜突蛋白虚拟酶解，对所得三肽的生物活性、亲水性、吸收、分布、代谢、排泄、毒性等性质进行预测，通过分子对接预测三肽与血管紧张素转化酶（angiotensin-I converting enzyme，ACE）对接能量，同时对其体外ACE抑制活性测定，并阐明与ACE活性位点的分子作用机制。结果表明，获得四种源自大黄鱼的ACE抑制三肽CMK，GWR，WAK和WQK，其IC₅₀值分别为0.19、2.40、0.40和1.10 mmol/L。分子作用机制表明三肽CMK，GWR，WAK和WQK与ACE的S₁口袋关键氨基酸Ala354，Glu384和S₂口袋关键氨基酸His353产生相互作用，而且氢键促进三肽与ACE活性口袋的结合。本研究表明来自大黄鱼蛋白的三肽可以被用于开发预防高血压的功能性食品组分。

Abstract: The moesin of Larimichthys crocea was in silico digested by gastrointestinal proteases(pepsin and trypsin) of online databases ExPASy PeptideCutter, and the potential bioactive, solubility, absorption, distribution, metabolism, excretion and toxicity of screened tripeptides were predicted and validated in this study. Furthermore, the interaction mechanism of tripeptides and angiotensin-I converting enzyme(ACE) was elucidated by molecular docking and the CDOCKER-Energy was calculated. The ACE inhibitory activity of potential tripeptides in vitro was determined by RP-HPLC and the interaction site of tripeptides in ACE was also clarified. In this paper, four ACE inhibitory tripeptides CMK, GWR, WAK and WQK were successfully identified from the moesin of Larimichthys crocea, with IC₅₀ values of 0.19, 2.40, 0.40, and 1.10 mmol/L respectively. The results of molecular interaction between tripeptides and ACE suggested that tripeptides CMK, GWR, WAK and WQK interacted with key residues Ala354, Glu384 in S₁ pocket of ACE and key residue His353 in S₂ pocket of ACE. Meanwhile, hydrogen bond may attribute to the molecular interaction of tripeptide and the active pocket of ACE. The current study indicated that tripeptides from Larimichthys crocea moesin could be used to develop functional food to prevent hypertension in the future.