Asymmetric effect of mechanical stress on the forward and reverse reaction catalyzed by an enzyme.

ABSTRACT: The concept of modulating enzymatic activity by exerting a mechanical stress on the enzyme has been established in previous work. Mechanical perturbation is also a tool for probing conformational motion accompanying the enzymatic cycle. Here we report measurements of the forward and reverse kinetics of the enzyme Guanylate Kinase from yeast (Saccharomyces cerevisiae). The enzyme is held in a state of stress using the DNA spring method. The observation that mechanical stress has different effects on the forward and reverse reaction kinetics suggests that forward and reverse reactions follow different paths, on average, in the enzyme's conformational space. Comparing the kinetics of the stressed and unstressed enzyme we also show that the maximum speed of the enzyme is comparable to the pred

SUBMITTER: Joseph C 

PROVIDER: S-EPMC4085160 | biostudies-literature | 2014

REPOSITORIES: biostudies-literature