Abstract

1. Although CYP2C19 is minor human liver enzyme, it is responsible for the metabolism of many clinically important drugs. In this work, CYP2C19 wild type and its SNP mutants (R132Q and W120R) were prepared using over-expression system in E. coli, purified by column chromatography and their biological activities were compared. The enzyme activity toward certain drugs (amitriptyline, imipramine, lansoprazole and omeprazole) was investigated.

2. Resonance Raman and UV–VIS spectroscopies revealed a minimal effect of SNP mutations on the heme structure. However, the mutation greatly affected the drug metabolism activities of CYP2C19. The degree of these effects was dependent on both the mutation and the chemical structure of the substrate.

3. Surprisingly, the affected amino acid residue is located remotely from the heme center. Therefore, the direct effect of the mutation on the metabolic center is excluded. Alternatively, the significant impairment in the drug metabolism of these mutants could be attributed to a decrease in the electron flow to the iron center.

4. Accordingly, understanding the effect of SNPs of CYP2C19, and the extents in which they participate in the drug metabolism, are important pillars that can enhance the therapeutic drugs efficacy and improve the patient outcomes toward the development of patient’s tailored medicine.

摘要

1. 尽管CYP2C19是次要的人肝酶，但它负责许多临床上重要的药物的代谢。本文利用大肠杆菌中的超表达系统制备了CYP2C19野生型及其SNP突变体（R132Q和W120R），并通过柱色谱法对其进行了纯化，并对其生物学活性进行了比较。研究了对某些药物（阿米替林，丙咪嗪，兰索拉唑和奥美拉唑）的酶活性。

2. 共振拉曼光谱和UV-VIS光谱分析显示SNP突变对血红素结构的影响极小。然而，该突变极大地影响了CYP2C19的药物代谢活性。这些作用的程度取决于底物的突变和化学结构。

3. 令人惊讶地，受影响的氨基酸残基位于血红素中心的远端。因此，排除了突变对代谢中心的直接影响。或者，这些突变体药物代谢的显着损害可归因于流向铁中心的电子流的减少。

4. 因此，了解CYP2C19的SNP的作用及其参与药物代谢的程度，是可以增强治疗药物功效并改善患者适应特制药物发展的重要支柱。