氨基酸序列分析问题：已知一个七肽的组成为:gly,phe（2）,tyr,met,asp,用胰凝乳蛋白酶水解

（2）是啥意思?2个the answer is : NH2-tyr-phe-asp-met-gly-arg-phe-COOH求详细的解析！！！谢谢First，FDNB is a technique to determine the n-* of the peptide, so the N-* of this polypeptide is tyr.then, pancreatic protease hydrolyze the polypeptide immediately after the carboxylic group of the acidic residue, that is asp, in this case. Since tyr, phe, and asp are together , the first 3 residues are : NH2-tyr-phe-asp.then, the pancreatic tripsin cuts the polypeptide after the carboxylic group of arg, so, the last two residues are -arg-phe-COOH.then, we are left with met and gly. Since arg, phe, gly are together,we now can be sure that the fourth one is met, and the fifth one is gly,so the final sequence is NH2-tyr-phe-asp-met-gly-arg-phe-COOHpancreatic protease hydrolyze the polypeptide immediately after the carboxylic group of the acidic residue, that is phe，not asp.