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Enzymes

Enzyme Active Site

• Amino acid side chains interact, metal ions,

• Various types of polar, non-polar, ionic interactions

Enzyme Active Site• Amino acid side chains interact, metal ions,

• Various types of polar, non-polar, ionic interactions

Enzymes• Lock and Key Analogy: lock = enzyme, key = substrate.

Enzymes• Lock and Key Analogy: lock = enzyme, key = substrate.

Induced Fit Theory

• Enzyme is not rigid, changes shape with substrate.

Induced Fit Theory

• Enzyme is not rigid, changes shape with substrate.

Enzymes - Cofactors

• Coenzymes (contain a vitamin) or metal ion

Enzymes - Cofactors

• Metal ions present in trace amounts

Enzymes - Cofactors

• Metal ions present in trace amounts

Enzyme Cofactors

• Coenzyme - non protein organic, maybe a vitamin.

Enzyme Cofactors

• Coenzyme - non protein organic, maybe a vitamin.

Enzyme Cofactors• Coenzyme - non protein organic, maybe a vitamin.

Enzymes

Enzymes - Activity

• Temperature and pH effect enzyme action

Enzymes - Activity

• Temperature and pH effect enzyme action

Enzymes - Activity

• Enzyme and substrate concentrations

Enzymes - Inhibitors

• Nonspecific - denaturation, pH, temperature

Enzyme Inhibitors

• Noncompetitive

Enzyme Inhibitors

• Competive - mimic substrate, may block active

site, but may dislodge it.

Enzyme Inhibitors• Competive - mimic substrate, may block active site, but

may dislodge it.

Enzyme Inhibitors

Enzyme Inhibitors

• Irreversible - covalently binds to active site

Enzyme Inhibitors

• Regulator or feedback - used to control a sequence

of reactions - reaction product may block initial

enzyme.

Enzyme Inhibitors• Regulator or feedback - used to control a sequence of

reactions - reaction product may block initial enzyme.

Enzyme Inhibitors

Enzyme Inhibitors

Drugs as Enzyme Inhibitors

• Drug mimics some natural chemical to block enzyme.

Drugs as Enzyme Inhibitors

• Drug mimics some natural chemical to block enzyme.