Biomimetic Natural Enzyme with Peptide-modified Gold Nanaoparticles
作者单位：Key Laboratory for Molecular Enzymology and Engineering of the Ministry of EducationJilin University
会议名称：《第十一届中国酶工程学术研讨会》
会议日期：2017年
学科分类：0710[理学-生物学] 071010[理学-生物化学与分子生物学] 081704[工学-应用化学] 07[理学] 08[工学] 0817[工学-化学工程与技术]
关 键 词：Nanotechnology Nanozyme Self-assembled monolayer(SAM) Glutathione peroxidase(GPx) mimic Bioactive peptide Gold nanoparticles Enzyme kinetics
摘 要：Selenopeptide(Sec-Arg-Gly-Asp-Cys,URGDC) and cysteamine-cofunctionalized gold nanoparticles monolayer protected cluster(MPC),catalyzes the reaction of H O by GSH,exhibiting Glutathione peroxidase(GPx)-like *** nanozyme was constructed through two self-assemble steps:First,URGDC was conjugated to AuNPs,forming a multivalent catalyst(MPC 1);second,the positively charged cysteamine was subsequently employed to optimize the enzyme activity by regulating the surface chemistry of gold nanoparticles(MPC 2).The systematical study of the catalytic capability showed that the Nanozyme catalyzed reaction exhibits saturation kinetics:the reactive rate data complied with the Michaelis-Menten model of enzyme kinetics,and the GPx activity of MPC land MPC 2 is 5.05 and 7.21 U/umol,about 14 and 20 times of that of free *** kinetic analysis indicated that the catalytic mechanism of free peptide is ping-pong mechanism,while it is the ordered mechanism for nanozyme(MPC 1,MPC 2).And the catalytic constant K/K of both GSH and H O are one order of magnitude higher than that of free *** manifested that gold nanoparticle as a scaffold excels in limiting the mobility and constraining conformation of URGDC,and the multivalent selenopeptide act cooperatively in the catalysis *** surface/interface regulationof gold nanoparticles facilitates the recognition and binding of *** rational design of nanozyme greatly improves and amplifies the catalytic activity of ’active unit’ *** work provides an alternative strategy to establish GPx mimic and new insights regarding the surface chemistry of AuNPs as a nanozyme.