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Fig.2. Decline in the phospho-protein concentration with distance from the cell
membrane at different values of the parameter
. The parameter
is determined by the ratio of the characteristic times of diffusion and the
phosphatase reaction
(
2=KpxL2/D,
where L is the cell radius,
Kp=Vmax,p/Km,p is
the observed first-order rate constant of the phosphatase and D is
the protein diffusion coefficient). The decline,
p(x)/p(1), is calculated as the ratio of the
concentrations of the phosphorylated form at distance xL from the
cell center and at the plasma membrane, where x=1. Reproduced with
permission from Kholodenko
(2002).