Abstract The enzymatic synthesis of methotrexate (MTX) catalysed by α -chymotrypsin was studied for the first time. The proteolytic enzyme displayed activity for the synthesis of MTX oligomers composed by 6 repeating units (DPavg = 1.5). For longer oligomers, molecular dynamics simulations confirmed that as the oligomeric chain grows its accommodation in the enzymes’ active site is hindered, which is evidenced by a decrease of the binding energy associated. The full characterization of the oligomers produced was performed by nuclear magnetic resonance (NMR, 1H and 13C), matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF), electrospray ionization (ESI) and differential scanning calorimetry (DSC).

中文翻译：

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α-胰凝乳蛋白酶催化甲氨蝶呤低聚物的合成

摘要 首次研究了α-胰凝乳蛋白酶催化合成甲氨蝶呤(MTX)。蛋白水解酶显示出合成由 6 个重复单元 (DPavg = 1.5) 组成的 MTX 寡聚体的活性。对于较长的低聚物，分子动力学模拟证实，随着低聚物链的增长，其在酶活性位点中的容纳受到阻碍，相关结合能的降低证明了这一点。通过核磁共振（NMR、1H 和 13C）、基质辅助激光解吸/电离飞行时间 (MALDI-TOF)、电喷雾电离 (ESI) 和差示扫描量热法 (DSC) 对所产生的低聚物进行全面表征.