Oxidation of 1-chloropyrene by human CYP1 family and CYP2A subfamily cytochrome P450 enzymes: catalytic roles of two CYP1B1 and five CYP2A13 allelic variants.
Oxidation of 1-chloropyrene by human CYP1 family and CYP2A subfamily cytochrome P450 enzymes: catalytic roles of two CYP1B1 and five CYP2A13 allelic variants.
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通过人CYP1家族和CYP2A亚家族细胞色素P450酶氧化1-氯吡啶的氧化：两个CYP1B1和五个CYP2A13等位基因变体的催化作用。
DOI：
10.1080/00498254.2017.1347306
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发表时间：
2018-06
期刊：
影响因子：
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通讯作者：
Komori M
中科院分区：
文献类型：
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作者：
Shimada T;Murayama N;Kakimoto K;Takenaka S;Lim YR;Yeom S;Kim D;Yamazaki H;Guengerich FP;Komori M
将氯代多环芳烃污染物之一氯代芘与人细胞色素P450（P450或CYP 1A 1）酶（包括CYP 1A 1、1A 2、1B 1、2A 6、2A 13、2B 6、2C 9、2D 6、2 E1、3A 4和3A 5）孵育。还检查了多态性的两个CYP 1B 1和五个CYP 2A 13等位基因变体在1-氯芘氧化中的催化差异。CYP 1A 1在6-和8-位比在3-位更活跃地氧化1-氯芘，而CYP1B1.1和1B1.3都优先催化6-羟基化。5个CYP 2A 13等位基因变体氧化8-羟基化的程度远高于6-和3-羟基化，发现变体CYP2A13.3缓慢催化这些反应，kcat值低于其他CYP2A13.1变体。CYP 2A 6催化1-氯芘6-羟基化的速率高于CYP 2A 13酶，但速率低于CYP 1A 1和1B 1变体。其他人类P450酶对1-氯芘的活性较低。分子对接分析表明1-氯芘与CYP 1和2A酶活性位点的相互作用存在差异。此外，发现CYP2A13.3中天然存在的Thr 134插入影响Asn 297在I-螺旋中与1-氯芘（以及4-（甲基亚硝胺基）-1-（3-吡啶基）-1-丁酮，NNK）相互作用的方向，并导致CYP2A13.3活性位点与CYP2A13.1相比发生变化。
Chloropyrene, one of the major chlorinated polycyclic aromatic hydrocarbon contaminants, was incubated with human cytochrome P450 (P450 or CYP) enzymes including CYP1A1, 1A2, 1B1, 2A6, 2A13, 2B6, 2C9, 2D6, 2E1, 3A4, and 3A5. Catalytic differences in 1-chloropyrene oxidation by polymorphic two CYP1B1 and five CYP2A13 allelic variants were also examined. CYP1A1 oxidized 1-chloropyrene at the 6- and 8-positions more actively than at the 3-position, while both CYP1B1.1 and 1B1.3 preferentially catalyzed 6-hydroxylation. Five CYP2A13 allelic variants oxidized 8-hydroxylation much more than 6- and 3-hydroxylation, and the variant CYP2A13.3 was found to slowly catalyze these reactions with a lower kcat value than other CYP2A13.1 variants. CYP2A6 catalyzed 1-chloropyrene 6-hydroxylation at a higher rate than the CYP2A13 enzymes, but the rate was lower than the CYP1A1 and 1B1 variants. Other human P450 enzymes had low activities towards 1-chloropyrene. Molecular docking analysis suggested differences in the interaction of 1-chloropyrene with active sites of CYP1 and 2A enzymes. In addition, a naturally occuring Thr134 insertion in CYP2A13.3 was found to affect the orientation of Asn297 in the I-helix in interacting with 1-chloropyrene (and also 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone, NNK) and caused changes in the active site of CYP2A13.3 as compared with CYP2A13.1.