Question

what are the strategies that enzymes use for catalysis (describe each below)

Acid-Base Catalysis

Covalent Catalysis

Metal ion Catalysis

Proximity and orientation effects

Answer 1

Solution

All of the following strategy are used by enzyme.

Acid-Base Catalysis

Covalent Catalysis

Metal ion Catalysis

Proximity and orientation effects

Acid-base catalysid:- functional groups in enzyme structure positioned to

donate proton act as avcid and to accept proton act as base.

it helps to avoid unstable charged intermediate in the reaction

Functional groups that acts as general acid-base

_Thiol group

-Carboxylic group

-Guanidine group

-imidazole group

covalent catalysis:- they accelarate the rate by transient formation of covalent enzyme substrate bond.

Covalent intermediate are mo reactive as they have lower activation energy.

Nucleophilic attack often involved in covalent catalysis.

Metal ion catalysi:- also known as prthestic group or metalloenzyme i.e Fe2+,Zn2+

Function

-Binding and orientation

-Redox reaction

-Shielding

All kinase enzymes require Mg2+ for activity.

proximity:- reaction between bound molecules does not require improbable collision between two molecules.

orientation:- reactant not only near each other on enzyme but they are oriented in optimal position to react.