5‐Methylcytosine is Oxidized to the Natural Metabolites of TET Enzymes by a Biomimetic Iron(IV)‐Oxo Complex
作者:Niko S. W. Jonasson、Lena J. Daumann
DOI:10.1002/chem.201902340
日期:2019.9.18
5mC is oxidized to 5hmC, 5fC, and 5cC by a biomimetic iron(IV)-oxo complex, reminiscent of the activity of TET enzymes. Studies show that 5hmC is preferentially turned over compared with 5mC and 5fC and that this is in line with the calculated bond dissociation energies. The optimized syntheses of d3 -5mC and d2 -5hmC are also reported and in the reaction with the biomimetic iron(IV)-oxo complex these
十一十一易位(TET)甲基胞嘧啶双加氧酶通过将表观遗传标记5-甲基胞嘧啶(5mC)氧化为5-羟甲基胞嘧啶(5hmC),5-甲酰基胞嘧啶(5fC)和5-羧基,在表观遗传学中发挥关键作用胞嘧啶(5cC)。尽管已经对5mC的许多新陈代谢进行了深入研究,但是某些方面(例如,观察到的TET酶催化活性与不同胞嘧啶底物的计算键解离能之间的差异)仍然难以捉摸。在此,据报道,仿生铁(IV)-氧代复合物将DNA碱基5mC氧化为5hmC,5fC和5cC,让人联想到TET酶的活性。研究表明,与5mC和5fC相比,优先选择5hmC进行翻转,这与计算得出的键解离能相符。还报道了d3 -5mC和d2 -5hmC的优化合成,并且在与仿生铁(IV)-氧代络合物的反应中,这些氘代底物表现出较大的动力学同位素效应,证实了氢的提取是限速步骤。综上所述,这些结果揭示了表观遗传标记的CH键的内在反应性以及TET酶中第二配位域的贡献。