  The cellular milieu is teeming with biochemical nano-machines whose activity
is a strong source of correlated non-thermal fluctuations termed "active
noise". Essential elements of this circuitry are enzymes, catalysts that speed
up the rate of metabolic reactions by orders of magnitude, thereby making life
possible. Here, we examine the possibility that active noise in the cell, or in
vitro, affects enzymatic catalytic rate by accelerating or decelerating the
crossing of energy barriers during reaction. Considering hydrodynamic
perturbations induced by biochemical activity as a source of active noise, we
attempt to evaluate their plausible impact on the enzymatic cycle using a
combination of analytic and numerical methods. Our estimate shows that the fast
component of the active noise spectrum may enhance the rate of enzymes, by up
to 50%, while reactions remain practically unaffected by the slow noise
spectrum and are mostly governed by thermal fluctuations. Revisiting the
physics of barrier crossing under the influence of active hydrodynamic
fluctuations suggests that the biochemical activity of macromolecules such as
enzymes is coupled to active noise, with potential impact on metabolic networks
in living and artificial systems alike.
