Department of Chemical and Biomolecular Engineering, The University of Melbourne, Melbourne, VIC 3010, Australia.
Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, P. R. China.
Sci Adv. 2020 Apr 1;6(14):eaaz0404. doi: 10.1126/sciadv.aaz0404. eCollection 2020 Apr.
The remarkable power of enzymes to undertake catalysis frequently stems from their grouping of multiple, complementary chemical units within close proximity around the enzyme active site. Motivated by this, we report here a bioinspired surfactant catalyst that incorporates a variety of chemical functionalities common to hydrolytic enzymes. The textbook hydrolase active site, the catalytic triad, is modeled by positioning the three groups of the triad (-OH, -imidazole, and -COH) on a single, trifunctional surfactant molecule. To support this, we recreate the hydrogen bond donating arrangement of the oxyanion hole by imparting surfactant functionality to a guanidinium headgroup. Self-assembly of these amphiphiles in solution drives the collection of functional headgroups into close proximity around a hydrophobic nano-environment, affording hydrolysis of a model ester at rates that challenge α-chymotrypsin. Structural assessment via NMR and XRD, paired with MD simulation and QM calculation, reveals marked similarities of the co-micelle catalyst to native enzymes.
酶具有强大的催化能力，通常是因为其在酶的活性部位附近将多个互补的化学单元聚集在一起。受此启发，我们在此报告了一种仿生表面活性剂催化剂，它包含了许多水解酶共有的化学功能。通过将三基团（-OH、-咪唑和-COH）置于单个三功能表面活性剂分子上来模拟教科书式的水解酶活性部位，即催化三联体。为了支持这一点，我们通过将表面活性剂官能团赋予胍基头部基团来重现阴离子空穴的氢键供体排列。这些两亲分子在溶液中的自组装促使功能头基在疏水纳米环境周围聚集在一起，从而实现了模型酯的水解，其水解速率可与α-糜蛋白酶相媲美。通过 NMR 和 XRD 进行结构评估，结合 MD 模拟和 QM 计算，揭示了共胶束催化剂与天然酶的显著相似性。
