What would be the result of an enzyme having a greater binding energy for the substrate than for the transition state?

Question

BlackTom AI · Accepted Answer

Question restatement: What would be the result of an enzyme having a greater binding energy for the substrate than for the transition state?

Option 1: There would be no catalytic activity. This is plausible because if the enzyme binds the substrate much more tightly than the transition state, the energy landscape favors the substrate state over the transition state, leading to a higher activation energy barrier and reduced or negligible rate enhancement. In catalytic terms, poor stabilization of the transition state relative to the substrate slows down catalysis and can essentially negate enzymatic activity.

Option 2: The catalytic activity would increase. This would imply the enzyme stabilizes the transition state more than the substrate, lowering the activation energy. Since the premise states the binding energy to the substrate is greater (i.e., substrate is more stabilized) than to the transition state, this option contradicts the given condition and is therefore incorrect.

Option 3: The equilibrium point would shift toward the reactants. In catalysis, the equilibrium between substrate and product is not two-way strongly altered by binding energies alone; enzymes primarily affect the rate (kinetics) rather than shifting the thermodynamic equilibrium unless they catalyze a reversible step with a different thermodynamic balance. While extremely unfavorable transition-state binding could tilt apparent equilibrium in some contexts, the core effect of stronger substrate binding relative to the transition state is to impede the reaction rate more than to reposition the equilibrium, making this option less precise and not the best description of the direct consequence.

Option 4: The catalytic activity would be unaffected. If the enzyme binds the substrate much more tightly than the transition state, that imbalance would alter the kinetic profile by raising the activation barrier; thus, asserting that activity is unaffected contradicts the consequence of mismatched binding energies. Therefore this is incorrect.

Summarizing the reasoning across options: The key idea is that enzymes accelerate reactions by stabilizing the transition state relative to the substrate. If binding is stronger to the substrate than to the transition state, stabilization of the transition state is poor, leading to a higher activation energy and diminished catalytic activity. Consequently, the option stating there would be no catalytic activity aligns with this mechanistic expectation, while the other choices conflict with how differential binding energies influence catalysis.

BIOL3611.13541.202610 FA2IndFA2025- Requires Respondus LockDown Browser

What would be the result of an enzyme having a greater binding energy for the substrate than for the transition state?

查看解析

登录即可查看完整答案

类似问题

Since citrate synthase exhibits sequential, ordered kinetics:

Indicate below the interpretation for the graph above

Indicate below the interpretation for the graph above

Which of the following is TRUE of a graph of velocity versus [S] in which the data were obtained when enzyme was added to the system? Please choose the correct answer from the following choices,

When KM is much greater than the [S]: Please choose the correct answer from the following choices

Vmax, the maximum velocity, of an enzyme-catalyzed reaction is

更多留学生实用工具

考试浏览器助手

风格化写作助手

论文查重助手

文献引用助手

课堂转译助手

课堂笔记助手

Quiz搜索助手

学校历年真题

智能刷题助手

智能匹配练习

希望你的学习变得更简单