Sections
Enzymes
Enzyme-Substrate Complex
Lock and Key Vs. Induced Fit Models
Optimal Enzyme Conditions
Activation Energy
Types of Enzymes
Cofactor
Catalysis
Electrostatic and Metal Ion Catalysis
Covalent Catalysis
Reaction Rate
Enzyme Kinetics
Rate Constants and Rate Law
Reaction Orders
Rate Constant Units
Initial Velocity
Vmax Enzyme
Km Enzyme
Steady-State Conditions
Michaelis-Menten Assumptions
Michaelis-Menten Equation
Lineweaver-Burk Plot
Michaelis-Menten vs. Lineweaver-Burk Plots
Shifting Lineweaver-Burk Plots
Calculating Vmax
Calculating Km
Kcat
Specificity Constant

Concept #1: The Lock and Key Model 

Concept #2: The Induced Fit Model

Practice: Compare the two enzyme-catalyzed reaction diagrams below (i & ii) to determine which of the following is true.

a) The ES-complex in diagram (i) is #2 and in diagram (ii) is #3..

b) Catalyzed EA in diagram (i) is arrow #5 and in diagram (ii) is arrow #7.

c) Binding energy in diagram (i) is arrow #5 and in diagram (ii) is arrow #7.

d) Diagram (i) describes a “lock & key” model while (ii) describes more of an “induced fit” model.

Practice: What is a potential disadvantage for an enzyme having too high of an affinity for its substrate?

Practice: Select the best option that fills in the blanks appropriately in the order of their appearance.

The left graph depicts an energy diagram for the “_____________” model of enzyme-substrate specificity, whereas the right diagram depicts an energy diagram for the modern “_____________” model. In the lock & key model, the enzyme binds tightly and precisely to the “_____________.” In the induced fit model, the enzyme binds weakly to the “_____________” and then changes conformation to bind tightly to the “_____________.”