Which of the reactants in the citric acid cycle have two chiral carbon atoms?

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All right. Hi everyone. So this question is asking us to determine if the following statement is true or false. Isocitrate is the only citric acid cycle component that has two chiral carbon atoms. Option A says true and option B says false. So first and foremost, it's important to have an understanding of the different intermediates found in the citric acid cycle. And just to clarify, recall that the citric acid cycle is a metabolic pathway, specifically a cab bolic metabolic pathway in which the storing material, Aceto coa is converted into carbon dioxide as well as various other co enzymes that are relevant in other metabolic pathways. Now, in the process of this at P is also produced. But for the purposes of this overview, I just very quickly want to kind of brief the intermediates that are produced. So I just want to focus on those here. And just as another quick reminder, recall that a chiral carbon atom refers to oops, it refers to a carbon atom with four different groups attached to it. So it has four different substituents connecting to that chiral carbon. So because of this SP two and SP carbons for that matter are not chiral, only sp three carbons that have four different substituents are considered chiral. So with that being said, let's talk about our intermediates. The first is citrate which is produced from the reaction between aceto koa and oxalacetate. Speaking of oxyl acetate, that's actually the product of step number eight, which is the final step in the citric acid cycle. Going back to the beginning though the second intermediate is isocitrate which is produced from the isomerization of citrate. From there isocitrate is converted into alpha keto glu rate. And the third step and in the fourth step, alpha Kogure is converted into succinate instead, five Succi succinyl coa is converted into succinate. And in step six, succinate is converted into fumarate. In step seven, we have fumarate being converted into mate or mate. And as mentioned before, the product of step eight is oxy acetate. So from this point onwards, it's important to get a sense of the structural features in all of the intermediates of the citric acid cycle. Not only does that help us answer a question like this, it also gives us a sense as to what's changing over the course of the citric acid cycle, right? What reactions are taking place? So in that analysis, we've arrived at the conclusion that there are two intermediates here that are Cairo and those are isocitrate and Malik. However, the distinguishing factor is that Mala only has one chiral carbon, specifically carbon two of the parent chain, whereas isocitrate has two chiral carbons, specifically those or specifically carbons two and three of the parent chain. And so the statement as it's written here is correct because isocitrate is not the only component that has chiral carbon atoms, but it is the only one that has two chiral centers. So the answer is a because the statement is true. And so with that being said, thank you so very much for watching. And I hope you found the thoughtful.

Which of the reactants in the citric acid cycle have two chiral carbon atoms?

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Key Concepts

Chirality

Citric Acid Cycle

Reactants in the Citric Acid Cycle