Enzyme Kinetics

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Enzyme Kinetics
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Introduction to Enzyme Kinetics

• Kinetics is the study of the rates at which
  chemical reactions occur
• Mechanism can be revealed by the effect of
  conditions on reaction rates
• Enzyme-catalyzed reactions are Reversible

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Chemical Kinetics
Elementary Reactions A gt P Reaction
Intermediates A gt I1 gt I2 gt P
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Rate Equations
aA bB gt P Rate kAaBb K rate
constant Order of Reaction a b
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Molecularity of Reaction

• First-order or unimolecular
• Second-order or bimolecular
• Etc.

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Rates of ReactionsFirst-Order Reactions
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Time Course of Reaction
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Second-Order Reaction
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Progress Curves
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Transition State
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Thermodynamics of the Transition StateA B gt
P Q
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Two-Step Reactions(Rate Determining Step)
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Accelerating Chemical Reactions(Heat)
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Accelerating Chemical Reactions(pH)
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Accelerating Chemical Reactions (Catalysis
Reduces ?G)
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Kinetics of Chemical Reactions
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First-Order Reaction
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Initial Velocity
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Enzyme Catalysis
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Michaelis-Menten Formulation
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Formation of Enzyme-Substrate Complex
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Progress Curves (M-M Enzyme)Steady-State
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Michaelis-Menten Equation
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Michaelis-Menten Equation
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Michaelis-Menton Enzyme Kinetics
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Lineweaver-Burk Plot
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Lineweaver-Burk Plot
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Accuracy of L-B Plots
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Eadie-Hofstee
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Eadie-Hofstee Plot
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Inhibition
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Competitive Inhibitor
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Competitive Inhibition
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Competitive Inhibitor Plots
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Non-Competitive Inhibitor
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Non-Competitive Inhibitor Plots
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Uncompetitive Inhibitor
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Uncompetitive Inhibitor Plots
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Value of Enzyme Kinetics

• Help Elucidate Mechanisms

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Effects of Inhibitors on the Parameters of the
M-M Equation