Fumarase from porcine heart

Fumarase (FH in human) is a well-known tricarboxylic-acid-cycle enzyme found in both the cytoplasm and mitochondria of all eukaryotes.

Fumarase is mapped to human chromosome 1q43. Fumarase comprises of three domains D1, D2 and D3 and belongs to class II fumarase family.

Fumarase from porcine heart has been used:

• as a positive control in isocitrate dehydrogenase and α-ketoglutarate dehydrogenase assay
• for immobilized enzyme based stability assay
• in fumarate hydratase assays in human lung carcinoma cells (A549)

Fumarase is used as a protein calibration standard in the purification of intact DNA polymerase a/primase from mouse cells.

Fumarase is essential for regulation of cellular metabolism. Fumarase elicits protective function from double-strand breaks (DSBs) induced by infrared radiation. Loss of function mutations in the fumarase gene is implicated in hereditary leiomyomatosis and renal cell cancer (HLRCC)-syndrome.

Fumarase catalyzes the reversible hydration of fumarate to malate. In its mitochondrial form, fumarate is involved in the Krebs Cycle, while the cytosolic form is involved in amino acid metabolism.

Suspension in 3.2 M (NH₄)₂SO₄, 0.05 M KH₂PO₄, pH 7.5, 0.014 M 2-mercaptoethanol

Isolated by the method of Beeckmans, S., and Kanarek, L., Eur. J. Biochem., 78, 437 (1977). Affinity purified.

One unit will convert 1.0 μmole of L-malate to fumarate per min at pH 7.6 at 25 °C.