Alcohol dehydrogenase (ADH) is and enzyme that can catalyze the oxidation of a n

Question

Alcohol dehydrogenase (ADH) is and enzyme that can catalyze the oxidation of a number of alcohols to the corresponding aldehyde. Two such reactions are:

ethanol CH3-CH2OH ————> CH3-CHO

butanol CH3-CH2-CH2-CH2OH ———> CH3-CH2-CH2-CHO

The Km for ethanol is 10-5M and the Km for butanol is 10-3M. Both substrates bind at the same active site, and the turnover number for each substrate is the same.

You have two test tubes with the same amounts of enzyme. One tube contains 10-1M butanol, the other 10-1M ethanol. Which alcohol will be oxidized faster?

ethanol

butanol

Neither, both will be oxidized at the same rate.

ethanol

butanol

Neither, both will be oxidized at the same rate.

Explanation / Answer

Michaelis-Menten equation can be written as,

V=Kcat[enzyme][S]/(Km+[S]

Kcat is the turnover number.

[S] is te substrate concentration

[enzyme] is the enzyme concentration.

Km is the Michaelis-Menten constant.Km is a measure how well a substrate bind with a enzyme.low Km value indicates large binding affinity ,high Km value indicates the enzyme does not bind efficciently with the substrate.

Km of ethanol is less than Km of butanol.Km for ethanol is 10-5M and Km for butanol is 10-3M.

so, V will be higher for ethanol.

ethanol will oxidize faster.

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.