Aldinio-Colbachini Anna, Fasano Andrea, Guendon Chloé, Jacq-Bailly Aurore, Wozniak Jérémy, Baffert Carole, Kpebe Arlette, Léger Christophe, Brugna Myriam, Fourmond Vincent
CNRS, Aix Marseille Université, BIP, IMM, IM2B 31 Chemin J. Aiguier, 13009 Marseille, France.
BBA Adv. 2023 Apr 22;3:100090. doi: 10.1016/j.bbadva.2023.100090. eCollection 2023.
Protein Film Electrochemistry is a technique in which a redox enzyme is directly wired to an electrode, which substitutes for the natural redox partner. In this technique, the electrical current flowing through the electrode is proportional to the catalytic activity of the enzyme. However, in most cases, the amount of enzyme molecules contributing to the current is unknown and the absolute turnover frequency cannot be determined. Here, we observe the formation of electrocatalytically active films of hydrogenase 1 by rotating an electrode in a sub-nanomolar solution of enzyme. This process is slow, and we show that it is mass-transport limited. Measuring the rate of the immobilization allows the determination of an estimation of the turnover rate of the enzyme, which appears to be much greater than that deduced from solution assays under the same conditions.
蛋白质膜电化学是一种将氧化还原酶直接连接到电极上的技术，该电极替代了天然的氧化还原伙伴。在这项技术中，流经电极的电流与酶的催化活性成正比。然而，在大多数情况下，对电流有贡献的酶分子数量是未知的，绝对周转频率也无法确定。在这里，我们通过在亚纳摩尔浓度的酶溶液中旋转电极，观察到氢化酶1的电催化活性膜的形成。这个过程很缓慢，我们证明它受传质限制。测量固定化速率可以确定酶周转速率的估计值，该值似乎远高于在相同条件下从溶液分析中推断出的值。
