血型A抗原模拟肽表位分析

Epitope analysis of peptide mimic of blood group A antigen

目的:通过计算机辅助的氨基酸定点突变及分子对接研究血型A抗原模拟多肽(EYWYCGMNRTGC)中关键的氨基酸残基。方法:通过在线服务器PEP-FOLD构建丙氨酸突变后多肽的三维结构,通过软件Autodock Vina将多肽与血型A抗体(PDB:1jv5)进行对接,计算亲和力,通过分析亲和力的变化确定模拟多肽中的关键氨基酸残基。结果:肽EYWYCGMNRTGC与1jv5的对接最小自由能为-6.3kcal/mol,其中E1、W3、T10、C12经丙氨酸替换后与1jv5的亲和自由能分别增加为-6.1kcal/mol、-5.4kcal/mol、-6.0kcal/mol、-6.1kcal/mol。结论:血型A抗原模拟肽EYWYCGMNRTGC中的关键氨基酸可能是E1、W3、T10、C12。

Objective：To investigate the key amino acids of peptide mimic（EYWYCGMNRTGC） of blood group A by computer aided molecular docking. Method：The peptide were substituted by alanine one by one. Web server of PEP-FOLD was used to construct the 3D structures of the original and substituted peptides. Autodock Vina software was used to predict the interaction between these peptides and monoclonal anti-A（PDB：1jv5）.The affinity value were calculate by this software. Result：The interaction between peptide and 1jv5 had the lowest energy of -6.3 kcal/mol. After substitution of E1,W3,T10 and C12 by alanine,the energy increased to -6.1 kcal/mol,-5.4 kcal/mol,-6.0 kcal/mol and -6.1 kcal/mol respectively. Conclusion：The key amino acids in peptide EYWYCGMNRTGC are E1,W3,T10 and C12.