Fumarase is a

Class I Fumarase enzyme, EC 4.2.1.2 (fumarate hydratase), which catalyzes the reversible hydration of fumarate to L-malate. ... Aspaate ammonia-lyase, EC 4.3.1.1 (aspaase), which catalyzes the reversible conversion of aspaate to fumarate and ammonia. 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 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