Title: Catalase
CAS Registry Number: 9001-05-2
Trademarks: Caperase; Equilase; Optidase (Sanofi Winthrop)
Literature References: Enzymes which promote reactions involving the decompn of hydrogen peroxide to water and oxygen. Although widely distributed among animals, plants, bacteria, and fungi, catalase in mammalian liver and blood has been most intensively studied. Catalase for commercial use obtained from animal liver, bacterial (Micrococcus lysodeikticus), and fungal (Aspergillus niger) sources. Isoln from mammalian livers and kidneys: Lolli, Cavanaugh, US 2703779 (1955 to Armour); Schroeder et al., Biochim. Biophys. Acta 58, 611 (1962); Dan, US 2992167 (1961 to Chr. Hansen's Lab.); from Aspergillus niger: Faucett et al., US 3102081 (1963 to Miles Labs.). All catalases so far isolated contain four tetrahedrally arranged subunits of equal size giving an approximate mol wt of 240,000. Each subunit consists of a single polypeptide chain associated with a single prosthetic group, ferric protoporphyrin IX. Amino acid sequence of bovine liver catalase subunit: Schroeder et al., Arch. Biochem. Biophys. 131, 653 (1969). Bovine hepatocatalase, a term for catalase obtained from liver, was reported to lower serum cholesterol; the active form was found to contain a catalytic amount of zinc (0.32%): Azarnoff, Curran, J. Lab. Clin. Med. 60, 856 (1962), cf. Laporte et al., Biochem. Pharmacol. 11, 670 (1962). Reviews: Nicholls, Schonbaum, in The Enzymes vol. 8, P. D. Boyer et al., Eds. (Academic Press, New York, 1963) pp 147-225; Deisseroth, Daunce, Physiol. Rev. 50, 319 (1970); Schonbaum, Chance, in The Enzymes vol. 13 (part C), P. D. Boyer, Ed. (Academic Press, New York, 3rd ed., 1976) pp 363-408.
Use: In combination with glucose oxidase, for treatment of food wrappers to prevent oxidative deterioration of food: Sarett, Scott, US 2765233 (1956 to Ben L. Sarett). In the removal of traces of peroxide in the process of cold sterilization (preservation of milk and cheese by treatment with hydrogen peroxide). With glucose oxidase, q.v., in food preservation.
Catalposide Catechu Black Catharanthine Cathepsins Catnep

PDB 7cat EBI.jpg
Symbol Catalase
Pfam PF00199
InterPro IPR011614
SCOP 7cat
OPM superfamily 435
OPM protein 3e4w
CDD cd00328
EC number
CAS number 9001-05-2
IntEnz IntEnz view
ExPASy NiceZyme view
MetaCyc metabolic pathway
PRIAM profile
PDB structures RCSB PDB PDBe PDBsum
Gene Ontology AmiGO / EGO

PDB rendering based on 1dgb.
Available structures
PDB Ortholog search: PDBe, RCSB
Symbols CAT (; MGC138422; MGC138424)
External IDs OMIM: 115500 MGI: 88271 HomoloGene: 55514 GeneCards: CAT Gene
EC number
RNA expression pattern
PBB GE CAT 201432 at tn.png
PBB GE CAT 211922 s at tn.png
More reference expression data
Species Human Mouse
Entrez 847 12359
Ensembl ENSG00000121691 ENSMUSG00000027187
UniProt P04040 P24270
RefSeq (mRNA) NM_001752 NM_009804
RefSeq (protein) NP_001743 NP_033934
Location (UCSC) Chr 11:
34.46 – 34.49 Mb
Chr 2:
103.45 – 103.49 Mb
PubMed search [1] [2]

Catalase is a common enzyme found in nearly all living organisms exposed to oxygen (such as vegetables, fruit or animals). It catalyzes the decomposition of hydrogen peroxide to water and oxygen.[1] It is a very important enzyme in protecting the cell from oxidative damage by reactive oxygen species (ROS). Likewise, catalase has one of the highest turnover numbers of all enzymes; one catalase molecule can convert millions of molecules of hydrogen peroxide to water and oxygen each second.[2]

Catalase is a tetramer of four polypeptide chains, each over 500 amino acids long.[3] It contains four porphyrin heme (iron) groups that allow the enzyme to react with the hydrogen peroxide. The optimum pH for human catalase is approximately 7,[4] and has a fairly broad maximum (the rate of reaction does not change appreciably at pHs between 6.8 and 7.5).[5] The pH optimum for other catalases varies between 4 and 11 depending on the species.[6] The optimum temperature also varies by species.[7]