What happens to aconitase when it binds iron?

Aconitase is a bifunctional enzyme that can either participate in the citric acid cycle or act as an iron regulatory protein depending on the presence of iron. When aconitase binds iron, a conformational change occurs in the protein structure. This change allows the enzyme to transition from its inactive form (where it can bind to mRNA and regulate iron metabolism) to an active form, facilitating its role in the citric acid cycle.

The structural alteration that results from iron binding is crucial for its function, as it helps the enzyme to properly engage in metabolic pathways. Understanding this conformational change is significant in cellular metabolism and iron regulation, emphasizing the dynamic relationship between iron availability and enzymatic function. This showcases the enzymatic versatility of aconitase depending on the cellular iron levels.