Chen Feng, Xue Jing, Bai Min, Qin Jing, Zhao Yongxi
Key Laboratory of Biomedical Information Engineering of Ministry of Education , School of Life Science and Technology , Xi'an Jiaotong University , Xianning West Road , Xi'an , Shaanxi 710049 , P. R. China . Email:
State Key Laboratory for Mechanical Behavior of Materials , School of Materials Science and Engineering , Xi'an Jiaotong University , Xianning West Road , Xi'an , Shaanxi 710049 , P. R. China.
Chem Sci. 2019 Jan 22;10(10):3103-3109. doi: 10.1039/c8sc05302b. eCollection 2019 Mar 14.
Macromolecule diffusion in cellular microenvironments dictates the kinetics of biochemical processes, yet inevitably limiting the assembly and operation of biomimetic motors. Herein we program accelerated DNA walkers in diffusion-limited microenvironments such as molecularly crowded solutions and cytoplasm. All DNA components, including single-foot walkers, chemically damaged tracks and calibration elements, are anchored on individual gold nanoparticles. Two endogenous enzymes participating in base repair pathways are used to actuate on-particle walking a base excision/hydrolyzation coupled reaction. The walkers are driven without requiring external drivers and accelerated several times. They also avoid low-efficiency diffusion/assembly procedures and respond to heterogeneous cellular milieus with calibration function. We further regulated the walking kinetics DNA densities and sets of enzymes, and demonstrated cytoplasmic behaviors of three kinds of walkers. They were utilized to profile DNA repair pathways and monitor enzyme catalysis in living cells.
细胞微环境中的大分子扩散决定了生化过程的动力学，但不可避免地限制了仿生马达的组装和运行。在此，我们在扩散受限的微环境（如分子拥挤的溶液和细胞质）中设计了加速的DNA步行器。所有的DNA组件，包括单足步行器、化学损伤的轨道和校准元件，都锚定在单个金纳米颗粒上。参与碱基修复途径的两种内源性酶被用于驱动颗粒上的行走——一种碱基切除/水解偶联反应。这些步行器无需外部驱动即可驱动，并加速了数倍。它们还避免了低效的扩散/组装过程，并通过校准功能对异质细胞环境做出反应。我们进一步通过DNA密度和酶的组合来调节行走动力学，并展示了三种步行器在细胞质中的行为。它们被用于描绘DNA修复途径并监测活细胞中的酶催化作用。
