Enzymes Flashcards
Large molecules that increase the rates of chemical reactions without themselves undergoing any change.
Enzymes
What does an enzyme do?
Provides an alternative pathway (shortcut) through lowering the activation energy
What name is given to the non-protein organic portion of an enzyme?
Coenzymes
What are the most used cofactors for enzymes?
metallic ions (zinc and magnesium)
What name is given to any non-protein portion of an enzyme that is metallic ions?
Cofactor
A protein portion of an enzyme that has cofactors or prosthetic groups.
Apoenzyme
What is the name given to a material which slows down enzyme function?
Inhibitor
What is the inhibitor that binds to the active site and prevents the binding of the substrate?
Competitive inhibitors
What is the inhibitor that binds to the active site and changes the shape of the active site?
Noncompetitive inhibitors
Where do non-competitive inhibitors bind?
Allosteric site
Where does the naming of enzymes base?
- On the reaction they catalyze
2. On the compound on which they act
How can you reverse the effect of competitive inhibitors?
By increasing the substrate concentration
What group of enzymes catalyze the removal of H2?
Oxidoreductases
What group of enzymes catalyze the transfer of a group of atoms?
Transferases
What group of enzymes catalyze the addition of H2O?
Hydrolases
What group of enzymes catalyze the joining of two molecules?
Ligases
What will cause the rate of enzyme activity to first increase and then level off or plateau?
By increasing the substrate concentration
What will cause the rate of enzyme activity to increase linearly without plateau?
By increasing the enzyme concentration
They are different forms of the same enzyme found in different tissues but used in the same reaction.
Isozymes
Aspartate transaminase transfers the amino group (NH3+) of aspartate to alpha-ketoglutarate. Which group does the enzyme belong to?
Transferase
What name is given to the binding of a substrate to an enzyme?
enzyme-substrate complex
What is the range of the pH at which the enzyme exhibits maximum activity?
7.0-7.5 pH
What do you call the limitation of an enzyme to catalyze specific reactions with specific substrates?
Substrate specificity
This type of enzymatic action where the substrate and enzyme do not exactly fit. Thus, the active site changes conformation/shape to allow binding.
induced-fit model