Question

Which of the following assumption was not made in rapid equilibrium model?

(a) Flexible nature of enzymes

(b) [S] >> [E]

(c) [E]+[S]\(\rightleftharpoons\)[ES]

(d) It is the initial substrate concentration [So] that determines efficacy of an enzyme to mediate a reaction

I had been asked this question in final exam.

This intriguing question comes from Kinetics of Enzyme Catalysed Reaction topic in section Enzyme Kinetics of Enzyme Technology

Answer 1

The correct choice is (a) Flexible nature of enzymes

Easy explanation: The flexible nature of enzymes was not dealt by lock and key model, but the induced fit model. This model dealt with change in shape after enzyme substrate interaction. The following assumptions were made in rapid equilibrium model:

* The substrate concentration will always be higher than enzyme concentration. [E] >> [S]

* An equilibrium state is assumed between reactants and products. [E]+[S]\(\rightleftharpoons\)[ES]

* It is the initial substrate concentration [So] that determines the efficacy of an enzyme to mediate a reaction.