A single-molecule analysis reveals morphological targets for cellulase synergy

作者:Fox Jerome M*; Jess Phillip; Jambusaria Rakesh B; Moo Genny M; Liphardt Jan; Clark Douglas S; Blanch Harvey W
来源:Nature Chemical Biology, 2013, 9(6): 356-+.
DOI:10.1038/nchembio.1227

摘要

The mechanisms of enzyme activity on solid substrates are not well understood. Unlike enzyme catalysis in aqueous solutions, enzyme activity on surfaces is complicated by adsorption steps and structural heterogeneities that make enzyme-substrate interactions difficult to characterize. Cellulase enzymes, which catalyze the depolymerization of cellulose, show binding specificities for different cellulose surface morphologies, but the influence of these specificities on the activity of multienzyme mixtures has remained unclear. We developed a metric to quantify binding-target arrangements determined by photoactivated localization microscopy, and we used that metric to show that combinations of cellulases designed to bind within similar but nonidentical morphologies can have synergistic activity. This phenomenon cannot be explained with the binary crystalline or amorphous classifications commonly used to characterize cellulase-binding targets. Our results reveal a strategy for improving the activity of cellulolytic mixtures and demonstrate a versatile method for investigating protein organization on heterogeneous surfaces.

  • 出版日期2013-6