What coenzymes are needed for the oxidation of pyruvate to acetyl CoA?

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All right. Hello everyone. So this question is asking us which of the following statements about the oxidation of pyruvate to acetyl coa is or are correct, select all that apply. So here on the screen, we have four different statements which we'll read individually later on, as well as four different answer. Choices labeled A through D proposing which statement or statements are correct. So before we go ahead and talk about the statements individually, let's just go ahead and briefly discuss the reaction in question, right? So first and foremost, we have pyruvate, let me actually scroll down just to open up some space. But in any case, our starting material is pyruvate. So here's pyruvate, right or starting material. And here we have pyruvate reacting with coenzyme A abbreviated here as HS coa with one equivalent of N A positive now N ad positive and its reduced form N A DH are important electron carriers, right? So as a result of this reaction, basically pyruvate and coenzyme A are combined to produce a pseudo coet. So we have the three carbons of our original pyruvate this time attached to the sulfur atom attached to coenzyme A. So thats aido Koe. And in addition, we also end up with one equivalent of carbon dioxide and N A positive is reduced to produce. Nah. Now recall that this reaction is catalyzed by the enzyme known as pyruvate dehydrogenase or pyruvate D as I'm abbreviating it here. So here it's important to also recognize that this particular reaction is such a crucial step during cellular respiration because this is what's connecting glycolysis to the citric acid cycle. But in any case with this context in mind, let's go ahead and start by looking at our statements starting off with statement number one here which says that N A positive is reduced to N A DH during the oxidation of pyruvate. This is true, right? Because as mentioned before, we have N A positive in the beginning and ND positive is reduced to N A DH as a result. So that's accurate statement two says that the reaction occurs in the cytoplasm of the cell. This unfortunately is not true. And the reason this is not true if you recall is because the oxidation of pyruvate actually takes place in the mitochondrial matrix, not in the cytoplasm. Moving on. From that we have statement number three, which reads that coenzyme A is required to form a pseudo coet. This is true, right? Because acetyl coa is the second crucial component of the reaction itself, it's the combination of pyruvate with coenzyme A. So statement three is true. Now, statement four reads that pyruvate oxidation directly produces a TP, which we can see is not correct based on our previous discussions on the reaction itself, right, what pyruvate oxidation directly produces are acetyl coa carbon dioxide and N A DH. So no A TP here. So from here, after going ahead and reviewing all of our answer choices or all of our statements, right? Of the four, given only statements, one and three are correct, which means that c is our correct answer and there you have it. So with that being said, thank you so very much for watching and I hope you found this helpful.

What coenzymes are needed for the oxidation of pyruvate to acetyl CoA?

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Key Concepts

Pyruvate Oxidation

Coenzymes in Metabolism

NAD+ and Coenzyme A