The influence of Mb and CK on the spatially averaged free or unbound O2 concentration, <O2> for εmito = 0.1 and O20 = 35.1 μM for cases (A) Without Mb and CK, (B) With Mb, (C) With CK, (D) With Mb and CK; <O2> is slightly higher in the presence of Mb for low Vmax,ATPase and large length scales whereas CK has no effect.