1. Rmax and Km (26.4)
Constants from Michaelis-Menten equation give insight into qualitative and quantitative aspects of enzyme kinetics
Indicate if enzyme inhibition is present and what type of inhibition is exhibited
Rmax is the maximum possible rate of conversion of substrate to product for a given enzyme
Km is related to how tightly an enzyme binds a substrate (the higher the value, the less tightly bound the substrate)
Inverting the Michaelis-Menten rate law gives an equation that can be useful for obtaining the maximum rate and the Michaelis constant
Lineweaver-Burk plot is generated by plotting 1/rate vs. 1/[S]
Lineweaver-Burk equation is more useful for getting constants since experiments can be done over a short range of substrate concentrations
y-intercept gives us Rmax, which is then used with the slope to get Km

2. Enzyme Inhibition (26.4)
Inhibition is a term used to describe the inability of a product being formed due to the presence of another substance (the inhibitor)
Enzyme inhibition can be competitive or noncompetitive
Competitive inhibition is caused when an inhibitor “competes” with the substrate in binding with the enzyme
Inhibitor decreases production of ES, thus decreasing product formation
Noncompetitive inhibition is caused when an inhibitor can bind to either the free enzyme or the enzyme-substrate complex
Inhibitor does not allow ES complex to convert to products

3. Enzyme Inhibition – Competitive (26.4)
Competitive inhibition does not affect the maximum rate of the catalytic process, but does slow down the process
Competitive inhibition can be eliminated by increasing the substrate concentration
Preequilibrium approximation is used to eliminate [ES] and [EI]
Lineweaver-Burk plots can be used to distinguish inhibition
For competitive inhibition, the maximum rate is unchanged (y-intercept is not dependent on [I])
The effective Michaelis constant (Km*) is dependent on inhibitor concentration
For different concentrations of inhibitor, LB plots give lines with different slopes

4. Michaelis-Menten Plot for Catalyzed Reaction of CO2 with H2O

5. Lineweaver-Burk Plot for Catalyzed Reaction of CO2 with H2O

6. Enzyme Inhibition

7. Competitive Inhibition