Gumpp Hermann, Puchner Elias M, Zimmermann Julia L, Gerland Ulrich, Gaub Hermann E, Blank Kerstin
Lehrstuhl für Angewandte Physik and Center for Nanoscience, Center for Integrated Protein Science Munich, LMU München, D-80799 München, Germany.
Nano Lett. 2009 Sep;9(9):3290-5. doi: 10.1021/nl9015705.
Integrating single molecule force spectroscopy with fluorescence-based techniques allows the manipulation of an enzyme with a periodic stretching and relaxation protocol while simultaneously monitoring its catalytic activity. After releasing the stretching force we observe a higher probability for enzymatic activity at a time of 1.7 s. A detailed theoretical analysis reveals that the relaxation from the force-induced enzyme conformation to the observed active conformation follows a cascade reaction with several steps and a free energy difference of at least 8 k(B)T. Our study clearly points out the direct influence of force on enzymatic activity and opens up a new way to study and manipulate (bio)catalytic reactions at the single molecule level.
将单分子力谱与基于荧光的技术相结合，能够通过周期性拉伸和松弛协议对酶进行操控，同时监测其催化活性。释放拉伸力后，我们观察到在1.7秒时酶活性出现的概率更高。详细的理论分析表明，从力诱导的酶构象到观察到的活性构象的松弛过程遵循一个包含多个步骤且自由能差至少为8k(B)T的级联反应。我们的研究清楚地指出了力对酶活性的直接影响，并开辟了一种在单分子水平上研究和操控（生物）催化反应的新方法。
