Proteolytic Enzyme

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proteolytic enzyme

[¦prōd·ē·ə¦lid·ik ′en‚zīm]
Any enzyme that catalyzes the breakdown of protein.

Proteolytic Enzyme


(also protease), an enzyme of the hydrolase class that is present in all living organisms. Proteolytic enzymes catalyze the hydrolysis of peptide bonds in both cellular and food proteins.

Proteolytic enzymes include peptidases (exopeptidases) and proteinases (endopeptidases). Peptidases primarily hydrolyze external peptide bonds in proteins and peptides, while proteinases hydrolyze the internal bonds. Proteolytic enzymes are subdivided according to the structural characteristics of their active center into metalloenzymes, each containing a metal atom, usually Zn, in its active center, and serine, thiolic (cys-teic), and acidic proteinases. Most of the known peptidases are metalloenzymes. Proteinases are also classed according to substrate specificity, that is, the ability to hydrolyze the bonds between specific amino-acid residues.

The sequence of amino acids in the molecules of a series of proteolytic enzymes has been determined. X-ray diffraction analysis has made it possible to determine the complete three-dimensional structure of several key proteinases, including pepsin, trypsin, and chymotrypsin. Proteolytic enzymes of the pancreas are synthesized in the form of inactive precursors—proenzymes—and therefore do not destroy the proteins of their parent tissue.

Preparations from proteolytic enzymes are used for many purposes; they are used in laboratories to determine the structure of proteins and peptides, in the food-processing industry when making cheese or tenderizing meat, in light industry to remove fur from hides and when bating leather, and in medicine to resorb thrombi and remove cataracts.


Neurath, H. “Fermenty, perevarivaiushchie belki.” In Molekuly ikletki. Moscow, 1966. (Translated from English.)
Mosolov, V. V. Proteoliticheskie fermenty. Moscow, 1971.


References in periodicals archive ?
Resolution of an Artifically Induced Hematoma and the Influence of a Proteolytic Enzyme.
BSH 1b, BSH 3a, BIP 4a, BIP lb and BRR 3a were found to be fully or partially inactivated by pepsin that was a proteolytic enzyme (Table l).
Proteolytic enzymes break down excess fibrin that has been linked to chronic systemic inflammation which feeds chronic diseases, including cancer.
Many pathogenic fungi produce proteolytic enzymes, and their activity determines their ability to use proteins of the host plant [13-15].
For example, carnivorous species exhibit a wide range and high activity of proteolytic enzymes to process their high-protein diet, whereas herbivores and omnivores ingest large amounts of carbohydrates (Johnston & Freeman 2005).
CAUTIONS: Proteolytic enzymes can thin the blood and increase the risk of bleeding, especially at higher doses.
Probably, the free amino acid present in yogurt was the result of hydrolysis of protein under the influnce of proteolytic enzymes.
1996, "Cell associated proteolytic enzymes from marine phytoplankton", J Phycol.
The calpain proteolytic enzyme system is responsible for the specific peptide bond cleavage which causes early postmortem tenderization [7].
The method is based on determining the level of a proteolytic enzyme in urine from the subject.
Bromelain is a proteolytic enzyme present in the stem and fruit of the pineapple plant (Ananas comosus), which was encountered by Christopher Columbus in Guadaloupe during his second voyage to the Caribbean in 1493.