中南药学

目的 鉴定宽体金线蛭、菲牛蛭肽段并对其进行生信预测分析。方法 采用浸渍、煎煮、仿生酶解不同时间的方式提取水蛭肽，UPLC-Q-Exactive-MS联合pFind Studio搜库、Peaks Studio从头测序鉴定肽段信息，借助生信平台对肽段的平均亲水性、等电点（pI值）、净电荷、不稳定性、活性概率、高活性概率肽段功能、毒性、致敏性等特征进行预测。结果 UPLC-Q-Exactive-MS联合pFind Studio搜库、Peaks Studio从头测序鉴定得到宽体金线蛭735条肽段、菲牛蛭765条肽段；生信分析初步预测水蛭肽特性，发现N端氨基酸种类为缬氨酸的水蛭肽占有相当比重，大部分水蛭肽的平均亲水性氨基酸比例在20%～60%,p I值在4～10，净电荷在-2～2，两种水蛭高活性概率肽段功能集中在抑制血管紧张素转换酶（ACE）、抑制二肽基肽酶Ⅳ（DPP-4）和抗血栓三个方面。结论 基于从头测序和多种提取方法对宽体金线蛭和菲牛蛭肽段进行了更准确更全面的鉴定，并利用生信分析进行特征预测，为其物质基础研究奠定了基础。

Objective To identify peptides of Whitmania pigra Whitman and Poecilobdella manillensis and predict the peptide characteristics with bioinformatics. Methods Leech peptides were obtained by immersion, decoction and enzymatic digestion at different time, and the peptide information was identified by UPLC-Q-Exactive-MS coupled with pFind Studio database searching and Peaks Studio de novo sequencing. The basic characteristics of the peptides such as hydrophilicity, pI value, net charge, instability, activity probability, high active probability peptide function, toxicity, sensitization and so on were predicted with bioinformatics platforms. Results UPLC-Q-Exactive-MS combined with pFind Studio database and Peaks Studio de novo sequencing identified 735 peptides from Whitmania pigra Whitman and 765 peptides from Poecilobdella manillensis. Preliminary prediction of leech peptide properties by bioinformatics revealed that leech peptides with valine as the N-terminal amino acid species accounted for a considerable proportion of the peptides, and most of the leech peptides had hydrophilic amino acid ratios ranging 20% to 60%, pI values ranging 4 to 10, and net charges ranging-2 to 2. Both leech high probability active peptide functions focused on inhibiting the angiotensin converting enzyme, dipeptidyl peptidase Ⅳ(DPP-4) and antithrombosis. Conclusion Based on the de novo sequencing and multiple extraction methods, the peptides of Whitmania pigra Whitman and Poecilobdella manillensis are identified more accurately and comprehensively, laying a solid foundation for the study of their material basis.