The reaction that follows is catalyzed by isocitrate dehydrogenase and occurs in two steps, the first of which (step A) is formation of an unstable intermediates (shown in brackets).


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c. Which of the structures shown can be described as a ß-keto acid?

Verified step by step guidance

1. Identify the structures provided in the problem and focus on their functional groups.
2. Recall that a $\beta$-keto acid is a compound that contains a ketone group (C=O) at the $\beta$-position relative to a carboxylic acid group (COOH).
3. Examine each structure to locate the carboxylic acid group (COOH).
4. From the carboxylic acid group, count two carbon atoms away to find the $\beta$-position.
5. Check if there is a ketone group (C=O) at the $\beta$-position in any of the structures to identify the $\beta$-keto acid.

Key Concepts

ß-keto acid

A ß-keto acid is a type of organic compound that contains a ketone group (C=O) adjacent to a carboxylic acid group (–COOH). This structure is significant in biochemistry as it plays a role in various metabolic pathways, including the citric acid cycle. The presence of both functional groups allows for unique reactivity, making ß-keto acids important intermediates in enzymatic reactions.

isocitrate dehydrogenase

Isocitrate dehydrogenase is an enzyme that catalyzes the oxidative decarboxylation of isocitrate to alpha-ketoglutarate in the citric acid cycle. This enzyme is crucial for cellular respiration, as it helps convert energy stored in carbohydrates into usable forms. Understanding its mechanism and the intermediates it produces is essential for grasping metabolic processes.

unstable intermediates

Unstable intermediates are transient species that form during chemical reactions and have a short lifespan before converting into more stable products. In enzymatic reactions, these intermediates can influence the reaction rate and pathway. Recognizing these intermediates is vital for understanding the dynamics of metabolic pathways and the role of enzymes in facilitating these transformations.