  Macromolecular crowding in living biological cells effects subdiffusion of
larger biomolecules such as proteins and enzymes. Mimicking this subdiffusion
in terms of random walks on a critical percolation cluster, we here present a
case study of EcoRV restriction enzymes involved in vital cellular defence. We
show that due to its so far elusive propensity to an inactive state the enzyme
avoids non-specific binding and remains well-distributed in the bulk cytoplasm
of the cell. Despite the reduced volume exploration capability of subdiffusion
processes, this mechanism guarantees a high efficiency of the enzyme. By
variation of the non-specific binding constant and the bond occupation
probability on the percolation network, we demonstrate that reduced
non-specific binding are beneficial for efficient subdiffusive enzyme activity
even in relatively small bacteria cells. Our results corroborate a more local
picture of cellular regulation.
