Multiple Choice
L-arginine is capable of binding to and activating N-acetylglutamate synthase. Since L-arginine is neither a substrate nor a product of this enzyme, how would this effector be classified?
324
views
2
rank
7. Enzyme Inhibition and Regulation
Allosteric Effectors
Multiple Choice
Which of the following statements about allosteric control of enzymatic activity is false?
A
Allosteric effectors give rise to sigmoidal V0 vs. [S] kinetic plots.
B
Allosteric proteins are generally composed of several subunits.
C
An allosteric effector may either inhibit or activate an enzyme.
D
Binding of the allosteric effector to the enzyme changes the conformation of the enzyme.
E
Heterotropic allosteric effectors compete with the substrate for binding sites on the enzyme.
Verified step by step guidance1
Understand the concept of allosteric control: Allosteric control involves the regulation of an enzyme's activity through the binding of molecules called allosteric effectors at sites other than the active site. This binding can alter the enzyme's conformation and activity.
Review the characteristics of allosteric enzymes: Allosteric enzymes often have multiple subunits and exhibit cooperative binding, which can lead to sigmoidal kinetic plots when plotting initial velocity (V0) against substrate concentration ([S]).
Differentiate between homotropic and heterotropic effectors: Homotropic effectors are typically the substrate itself, while heterotropic effectors are different molecules that bind to the enzyme and modulate its activity.
Examine the statement about heterotropic effectors: Heterotropic allosteric effectors do not compete with the substrate for binding at the active site; instead, they bind at distinct allosteric sites, influencing enzyme activity indirectly.
Identify the false statement: The statement claiming that heterotropic allosteric effectors compete with the substrate for binding sites is incorrect, as they bind at separate allosteric sites, not the active site.
Related Videos
Related Practice
