Propagation of Enzyme-Driven Active Fluctuations in Crowded Milieu

Abstract

The recently observed capability of active enzyme molecules to transduce mechanical energy during catalytic turnover and thereby influence the dynamics of their surroundings, akin to the adenosine triphosphate (ATP)-driven molecular motors, has opened up new research avenues in molecular biophysics. In this study, the energy transfer from active enzymes to their surroundings in crowded environments is investigated by measuring the diffusion of passive microscopic tracers in active solutions of ficoll and glycerol. Despite observing lower rates of substrate turnover, a significantly higher relative enhancement of passive tracer diffusion is found in crowded environments compared to those in aqueous solutions in the presence of enzymatic activity. The experimental observations, coupled with supporting theoretical estimations, underscore the possible role of the intervening media in facilitating mechanical energy distribution around active enzymes, which might have important implications over various biochemical processes in active intracellular milieu.

Keywords: Catalysis; Crowders; Enhanced Diffusion; Enzymes; Nanomotors; Tracers.