Question

How does an enzyme lower the activation energy of a biochemical reaction?

Answer 1

I know the substrate binds to the enzyme, H2O is added to break the alpha 1,4 glycosidic bond, but I still dont get how does this lowers the activation energy

Answer 2

Enzymes lower the activation energy of a reaction by positioning a reactant (or multiple reactants) in very specific conformations and positions. Essentially enzymes are dynamic scaffolds on which reactants are positioned in such a way that the reaction becomes more likely to happen. The activation energy - the energy of the transition state - is lowered, but the relative energies of the reactant(s) and product(s) are not affected.

Clear?

Answer 3

What do you mean by positioning the reactant..?? You mean it is place in a different location? or u mean the structure?
so can the induced fit model be applied to here?

Answer 4

The reactant binds the enzyme at a very specific site on that enzyme. That site places the reactant in a unique and very specific chemical environment. For example, perhaps a bonding group in the reactant is positioned near a polarizing group in the enzyme. That positioning makes it more likely that the bonding group in the reactant will actually undergo a chemical reaction.

The enzyme is a dynamic scaffold. Sometimes binding of the reactant(s) induces a conformational change in the enzyme (the unbound but bindable and fully bound states of the enzyme differ) which make the reaction more likely to happen.

Answer 5

oh ok i get it thanks

Answer 6

Cool. ;D