What is "fumarase"

n. An enzyme that in the Krebs cycle acts as a catalyst for the reaction of water and fumarate to form L-malate.

Fumarase (or fumarate hydratase) is an enzyme that catalyzes the reversible hydration/ dehydration of fumarate to malate. Fumarase comes in two forms: mitochondrial and cytosolic. The mitochondrial isoenzyme is involved in the Krebs Cycle (also known as the Tricarboxylic Acid Cycle [TCA] or the Citric Acid Cycle), and the cytosolic isoenzyme is involved in the metabolism of amino acids and fumarate. Subcellular localization is established by the presence of a signal sequence on the amino terminus in the mitochondrial form, while subcellular localization in the cytosolic form is established by the absence of the signal sequence found in the mitochondrial variety.

This enzyme participates in 2 metabolic pathways: citric acid cycle, reductive citric acid cycle (CO fixation), and is also important in renal cell carcinoma. Mutations in this gene have been associated with the development of leiomyomas in the skin and uterus in combination with renal cell carcinoma.