Enzymes half-saturation

[Dave]

Dear All,

We all more or less think that the concentrations of substrates in vivo
are
close to the half-saturation of enzymes. Well, I am trying to find the
experimental
data that confirms this. For Michaelis-Menten enzymes the best I find is
a table
in Fersht's book on enzymes of the values of K_m/[S] for several
enzymes.
I am trying to find a similar table or articles for allosteric enzymes.
Do you know of any?

Thank you for your time !!!!!!!!