faizan_ahmad

I thank both of you! We equilibrate the enzyme in urea solution. The enzyme is, say 25%, denatured as measured by several conformational properties. Our buffer and substrate solutions contain the same amount of urea. So all activity measurements are done at constant urea solution. I am sure you will now come up with different answers for Km and Vmax now.

Thanks! I am sure your argument is that Km is not a function of [E]. We have measured Km of the enzyme in the presence and absence of urea which shifts the N state <--> D state equilibrium from left to the right. We have observed that Km is increased in the presence of urea. Then this argument fails to explain this observation. FA

An enzyme in the native buffer solution exists in the equilibrium, native (N) state <--> denatured (D) state. So it has its KM and Vmax in this buffer. If one adds a cosolute to the enzyme solution, and if the cosolute shifts the equilibrium from D state to N state (i.e., the enzyme gets stabilized), then will the cosolute also effect the KM and Vmax?