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Comman Enzyme Mechanism

Type of Catalysis

Mechanism

Amino Acids/Actions Commonly Involved

Approximation

Holds reactants in correct orientation for reaction to occur

Charge density, polarity, solvation, active site configuration

Acid/Base

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

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

Nucleophilicity

Donates electrons for enzyme-substrate intermediate formation

Asp, Ser, Cys, His, Glu

Electrophilicity

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