What type of reaction is involved in the conversion of citrate to isocitrate?

The conversion of citrate to isocitrate is classified as an isomerization reaction. This process involves the rearrangement of the molecular structure of the citrate molecule to form isocitrate, which has the same molecular formula but a different arrangement of atoms. Isomerization specifically refers to reactions where the product is an isomer of the reactant.

During this reaction, an intermediate, cis-aconitate, is formed as part of the isomerization process, with a reconfiguration of the hydroxyl group and the position of a carboxyl group. This crucial step allows the citrate molecule to change its configuration without altering its overall formula, moving it from a tertiary alcohol form to a secondary alcohol form in isocitrate.

This reaction is important within the citric acid cycle as it prepares the substrate for subsequent reactions that lead to energy production. The specificity of isomerization highlights how metabolic pathways utilize such transformations to facilitate ongoing biochemical processes.