Narayan Alison R H, Jiménez-Osés Gonzalo, Liu Peng, Negretti Solymar, Zhao Wanxiang, Gilbert Michael M, Ramabhadran Raghunath O, Yang Yun-Fang, Furan Lawrence R, Li Zhe, Podust Larissa M, Montgomery John, Houk K N, Sherman David H
Life Sciences Institute, University of Michigan, Ann Arbor, Michigan 48109, USA.
Department of Chemistry, University of California, Los Angeles, California 90095, USA.
Nat Chem. 2015 Aug;7(8):653-60. doi: 10.1038/nchem.2285. Epub 2015 Jun 29.
The hallmark of enzymes from secondary metabolic pathways is the pairing of powerful reactivity with exquisite site selectivity. The application of these biocatalytic tools in organic synthesis, however, remains under-utilized due to limitations in substrate scope and scalability. Here, we report how the reactivity of a monooxygenase (PikC) from the pikromycin pathway is modified through computationally guided protein and substrate engineering, and applied to the oxidation of unactivated methylene C-H bonds. Molecular dynamics and quantum mechanical calculations were used to develop a predictive model for substrate scope, site selectivity and stereoselectivity of PikC-mediated C-H oxidation. A suite of menthol derivatives was screened computationally and evaluated through in vitro reactions, where each substrate adhered to the predicted models for selectivity and conversion to product. This platform was also expanded beyond menthol-based substrates to the selective hydroxylation of a variety of substrate cores ranging from cyclic to fused bicyclic and bridged bicyclic compounds.
来自次生代谢途径的酶的标志是强大的反应活性与精确的位点选择性相结合。然而，由于底物范围和可扩展性的限制，这些生物催化工具在有机合成中的应用仍未得到充分利用。在此，我们报告了如何通过计算指导的蛋白质和底物工程来修饰来自苦霉素途径的单加氧酶（PikC）的反应活性，并将其应用于未活化亚甲基C-H键的氧化反应。利用分子动力学和量子力学计算来开发一个预测模型，用于预测PikC介导的C-H氧化反应的底物范围、位点选择性和立体选择性。通过计算筛选了一组薄荷醇衍生物，并通过体外反应进行评估，其中每个底物都符合选择性和转化为产物的预测模型。该平台还扩展到基于薄荷醇的底物之外，用于各种底物核心的选择性羟基化，这些底物核心从环状化合物到稠合双环和桥连双环化合物不等。
