Chapter 16: Problem 53
Methanol and ethanol are oxidized by alcohol dehydrogenase. In methanol poisoning, ethanol is given intravenously to prevent the formation of formaldehyde that has toxic effects. a. Draw the condensed structural formulas of methanol and ethanol. b. Would ethanol compete for the active site or bind to a different site? c. Would ethanol be a competitive or noncompetitive inhibitor of methanol oxidation?
Short Answer
Step by step solution
Key Concepts
These are the key concepts you need to understand to accurately answer the question.
Methanol Poisoning
Symptoms of methanol poisoning include headache, dizziness, nausea, and blurred vision.
It may also take from 12 to 24 hours for symptoms to appear. If a person is suspected of methanol poisoning, they must receive immediate medical attention.
Ethanol
However, when used medically, it can act as an antidote to methanol poisoning. This is because ethanol competes with methanol for metabolism by the same enzyme, alcohol dehydrogenase.
By administering ethanol, the metabolism of methanol is slowed down, which allows more time for methanol to be excreted from the body.
Competitive Inhibition
In the context of methanol poisoning, ethanol competes with methanol for the active site on the enzyme alcohol dehydrogenase. This competition prevents methanol from being converted into toxic formaldehyde.
As a result, ethanol can be used to mitigate the toxic effects of methanol ingestion.
Active Site
Alcohol dehydrogenase, the enzyme in question, has an active site that binds to both methanol and ethanol.
When ethanol is present, it blocks methanol from binding to the active site, thereby preventing the enzyme from converting methanol into toxic products.
Oxidation
In the case of alcohol dehydrogenase, this enzyme catalyzes the oxidation of methanol to formaldehyde and ethanol to acetaldehyde.
These reactions involve the loss of electrons from the alcohols, turning them into aldehydes.
The oxidation of methanol is particularly harmful because formaldehyde is toxic, whereas the byproducts of ethanol oxidation are less harmful in the short term.