Problem 8 - Biochemistry

Question

Pyruvate carboxylase is often considered a gluconeogenic enzyme; however, it also plays an important role in an energy-converting pathway under conditions of low energy charge and high acetyl-CoA levels in mitochondria. What is the name of this pathway?

Step-by-Step Solution

Answer

Answer: Anaplerotic pathway

Step 1: Identify the role of pyruvate carboxylase in metabolic pathways

Pyruvate carboxylase is an enzyme that catalyzes the carboxylation of pyruvate to oxaloacetate. This reaction is an important step in various metabolic pathways, including gluconeogenesis and the citric acid cycle.

Step 2: Recognize the pathway with specific conditions

Under conditions of low energy charge and high acetyl-CoA levels in mitochondria, anaplerotic reactions are crucial to replenish the citric acid cycle intermediates. Pyruvate carboxylase plays a critical role in one of these anaplerotic reactions.

Step 3: Name the pathway

The pathway in which pyruvate carboxylase plays an important role under conditions of low energy charge and high acetyl-CoA levels in mitochondria is called the "Anaplerotic pathway."