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Comman Enzyme Mechanism

Type of Catalysis


Amino Acids/Actions Commonly Involved


Holds reactants in correct orientation for reaction to occur

Charge density, polarity, solvation, active site configuration


Lowers transition state energy of substrate or intermediate by proton addition or removal

Asp, Glu, His, Lys, Tyr, Arg, Cys, metal ions


Donates electrons for enzyme-substrate intermediate formation

Asp, Ser, Cys, His, Glu


Withdraws electrons for enzyme-substrate intermediate formation

Lys, Arg, His; thiamine pyrophosphate, pyridoxal phospate, metal ions

Distortion or torsional strain

Binding forces lower enzyme-substrate intermediate transition state energy

Charge density, polarity, and solvation of active site; active site configuration and flexibility