Enzymes Flashcards
(12 cards)
What are the main characteristics of enzymes?
Specificity: Act on specific substrates.
Efficiency: Dramatically increase reaction rates.
Regulation: Activity can be modulated.
What are cofactors and coenzymes?
Cofactors: Non-protein molecules required for enzyme activity (e.g., metal ions).
Coenzymes: Organic molecules that assist enzymes (e.g., NAD+, FAD).
What is the lock-and-key model?
Proposes that the enzyme’s active site and substrate fit together perfectly.
What is the induced fit model?
Suggests that the enzyme changes shape to better fit the substrate upon binding.
What is the Michaelis-Menten equation?
V= Vmax*conc/Km+conc
What is allosteric regulation?
Enzyme activity is modulated by molecules binding to sites other than the active site, causing conformational changes.
What is feedback inhibition?
A product of a metabolic pathway inhibits an enzyme earlier in the pathway to regulate production.
What are the six classes of enzymes?
Oxidoreductases: Catalyze oxidation-reduction reactions.
Transferases: Transfer functional groups between molecules.
Hydrolases: Break bonds using water.
Lyases: Break bonds without water or oxidation.
Isomerases: Rearrange atoms within a molecule.
Ligases: Join two molecules using ATP.
What is the role of enzymes in metabolism?
Facilitate metabolic reactions, ensuring efficiency and specificity.
What is enzyme specificity?
Absolute specificity: Acts on only one substrate.
Group specificity: Acts on substrates with specific functional groups.
Bond specificity: Acts on specific types of bonds.
How are enzymes used in clinical diagnostics?
Biomarkers for diseases (e.g., elevated levels of liver enzymes indicate liver damage).
Enzyme-based assays (e.g., glucose oxidase for blood sugar testing).
What is the importance of enzyme structure?
The three-dimensional structure determines substrate binding and catalytic activity.
