Kanehira Yuya, Kogikoski Sergio, Titov Evgenii, Tapio Kosti, Mostafa Amr, Bald Ilko
Institute of Chemistry, University of Potsdam, 14476 Potsdam, Germany.
Dynamics of Molecules and Clusters Department, J. Heyrovský Institute of Physical Chemistry of the CAS, Dolejškova 3, 18223 Prague, Czech Republic.
ACS Nano. 2024 Jul 29;18(31):20191-200. doi: 10.1021/acsnano.4c03384.
The detection of a single-enzyme catalytic reaction by surfaced-enhanced Raman scattering (SERS) is presented by utilizing DNA origami-based plasmonic antennas. A single horseradish peroxidase (HRP) was accommodated on a DNA origami nanofork plasmonic antenna (DONA) containing gold nanoparticles, enabling the tracing of single-molecule SERS signals during the peroxide reduction reaction. This allows monitoring of the structure of a single enzymatic catalytic center and products under suitable liquid conditions. Herein, we demonstrate the chemical changes of HRP and the appearance of tetramethylbenzidine (TMB), which works as a hydrogen donor before and after the catalytic reaction. The results show that the iron in HRP adopts Fe and low spin states with the introduction of HO, indicating compound-I formation. Density functional theory (DFT) calculations were performed for later catalytic steps to rationalize the experimental Raman/SERS spectra. The presented data provide several possibilities for tracking single biomolecules in situ during a chemical reaction and further developing plasmon-enhanced biocatalysis.
利用基于DNA折纸的等离子体天线，通过表面增强拉曼散射（SERS）实现了对单酶催化反应的检测。将单个辣根过氧化物酶（HRP）置于含有金纳米颗粒的DNA折纸纳米叉等离子体天线（DONA）上，从而能够在过氧化物还原反应过程中追踪单分子SERS信号。这使得在合适的液体条件下监测单个酶催化中心的结构和产物成为可能。在此，我们展示了HRP的化学变化以及催化反应前后作为氢供体的四甲基联苯胺（TMB）的出现。结果表明，随着HO的引入，HRP中的铁呈现Fe和低自旋态，表明形成了化合物-I。对后续催化步骤进行了密度泛函理论（DFT）计算，以合理解释实验拉曼/SERS光谱。所呈现的数据为在化学反应过程中原位追踪单个生物分子以及进一步发展等离子体增强生物催化提供了多种可能性。
