Ch. 7 - Enzyme Inhibition and Regulation WorksheetSee all chapters
All Chapters
Ch. 1 - Introduction to Biochemistry
Ch. 2 - Water
Ch. 3 - Amino Acids
Ch. 4 - Protein Structure
Ch. 5 - Protein Techniques
Ch. 6 - Enzymes and Enzyme Kinetics
Ch. 7 - Enzyme Inhibition and Regulation
Ch. 8 - Protein Function
Ch. 9 - Carbohydrates
Ch. 10 - Lipids
Ch. 11 - Biological Membranes and Transport
Ch. 12 - Biosignaling
Clutch Review 1: Nucleic Acids, Lipids, & Membranes
Clutch Review 2: Biosignaling, Glycolysis, Gluconeogenesis, & PP-Pathway
Clutch Review 3: Pyruvate & Fatty Acid Oxidation, Citric Acid Cycle, & Glycogen Metabolism
Clutch Review 4: Amino Acid Oxidation, Oxidative Phosphorylation, & Photophosphorylation
Sections
Enzyme Inhibition
Irreversible Inhibition
Reversible Inhibition
Inhibition Constant
Degree of Inhibition
Apparent Km and Vmax
Inhibition Effects on Reaction Rate
Competitive Inhibition
Uncompetitive Inhibition
Mixed Inhibition
Noncompetitive Inhibition
Recap of Reversible Inhibition
Allosteric Regulation
Allosteric Kinetics
Allosteric Enzyme Conformations
Allosteric Effectors
Concerted (MWC) Model
Sequential (KNF) Model
Negative Feedback
Positive Feedback
Post Translational Modification
Ubiquitination
Phosphorylation
Zymogens

Concept #1: Inhibition Constant

Example #1: A) Consider the data in the chart below.  Which enzyme has the strongest binding affinity for its substrate?
B) Which enzyme has the strongest binding affinity for its inhibitor?

Concept #2: Inhibition Constant of Free Enzyme (E)

Practice: Use the data in the chart below to determine the answer to the following:

A) Rank the enzymes in order of their binding affinity to their substrate (strongest affinity → weakest affinity).

a) A → B → C. 

b) C → A → B. 

c) C → B → A. 

d) B → A → C.

B) Rank the enzymes in order of their binding affinity to the inhibitor (strongest affinity → weakest affinity).

a) A → B → C. 

b) B → C → A. 

c) C → B → A. 

d) B → A → C.

C) Which enzyme would you expect the inhibitor to affect the most? Why?

a) Enzyme A. 

b) Enzyme B. 

c) Enzyme C.

Concept #3: Inhibition Constant of ES-Complex

Practice: Calculate the Michaelis constant (Km) and the inhibition constant (K I) given the following information:

[E] = 20 mM. [S] = 15 mM. [ES] = 5 mM. [I] = 8 mM. [EI] = 2 mM.