which of the following statements about the enzyme whose activity is illustrated
ID: 1064730 • Letter: W
Question
which of the following statements about the enzyme whose activity is illustrated in curve 5 is true.
a)this enzyme most likely catalyzes a metabolically reversible equilibrium reaction.b) this enzyme does not have quaternary structure. c) this enzyme undergoes a change in shape via a process termed cooperativity d) the substrate of this enzyme inhibits its activity.
Explanation / Answer
Ans. a) this enzyme most likely catalyzes a metabolically reversible equilibrium reaction.
Incorrect: The reaction rate vs substrate concentration demonstrates the rate of reaction with respect to [S]. It does not specify reversibility of the reaction.
b) this enzyme does not have quaternary structure.
Incorrect: Rate vs [S] plot does not specify quaternary structure.
c) this enzyme undergoes a change in shape via a process termed cooperativity.
Correct: The sigmoid shape of the curve indicates positive cooperativity of the enzyme or protein activity/catalysis. It is noteworthy, most of the enzymes/ proteins exhibiting cooperativity have quaternary structures (multi-subunit proteins), but a protein with tertiary structure (monomeric protein) may also exhibit cooperativity.
d) the substrate of this enzyme inhibits its activity.
Incorrect: Rate vs [S] curve does not specify enzyme inhibitions on its own unless compared with another curve plotted in presence of an inhibitor or molecule other than the reaction mixture constituents.