Papain
Papain family cysteine protease | |||||||||
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papain | |||||||||
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ExPASy | NiceZyme view | ||||||||
KEGG | KEGG entry | ||||||||
MetaCyc | metabolic pathway | ||||||||
PRIAM | profile | ||||||||
PDB structures | RCSB PDB PDBe PDBsum | ||||||||
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Papain, also known as papaya proteinase I, is a cysteine protease (EC 3.4.22.2) enzyme present in papaya (Carica papaya) and mountain papaya (Vasconcellea cundinamarcensis). It is the namesake member of the papain-like protease family.
It has wide ranging commercial applications in the leather, cosmetic, textiles, detergents, food and pharmaceutical industries. In the food industry, papain is used as an active ingredient in many commercial meat tenderizers.[1]
Papain family
Papain belongs to a family of related proteins, known as the
Structure
The papain precursor protein contains 345 amino acid residues,
Function
The mechanism by which papain breaks
Papain is a relatively heat-resistant enzyme, with an optimal temperature range of 60 to 70 °C.[9]
Papain prefers to cleave after an
Uses
This section needs additional citations for verification. (February 2014) |
Papain breaks down tough meat fibres, and has been used since before European contact to tenderise meat eaten in its native South America. Meat tenderisers in powder form with papain as an active component are widely sold and the culinary use of papaya peel has featured in research papers.[1][11]
Papain can be used to dissociate cells in the first step of
It is also used as an ingredient in various enzymatic debriding preparations, notably Accuzyme. These are used in the care of some chronic wounds to clean up dead tissue.
Papain is added to some toothpastes and mint sweets as a tooth whitener. Its whitening effect is minimal, because the papain is present in low concentrations and is quickly diluted by saliva. It would take several months of use to have a noticeable effect.[12]
Papain is the main ingredient of Papacarie, a gel used for chemomechanical
Papain has been known to interfere with urine drug tests for cannabinoids.[14] It is found in some drug detox products.
Recently, it has been demonstrated that papain can be used to assemble
Papain has also been used to create a degenerated disc disease model to assess various types of injectable therapies.[16][17]
Immunoglobulins
An
Production
Papain is usually produced as a crude, dried material by collecting the latex from the fruit of the papaya tree. The latex is collected after scoring the neck of the fruit, where it may either dry on the fruit or drip into a container. This latex is then further dried. It is now classified as a dried, crude material. A purification step is necessary to remove contaminating substances. This purification consists of the solubilization and extraction of the active papain enzyme system through a government-registered process. This purified papain may be supplied as powder or as liquid.
US restrictions on marketing
On September 23, 2008, the US Food and Drug Administration (FDA) warned companies to stop marketing ophthalmic balanced salt solutions and topical drug products containing papain by November 4, 2008. The FDA said, "Papain-containing drug products in topical form historically have been marketed without approval...".[18] According to the FDA's statement on the subject, "These unapproved products have put consumers' health in jeopardy, from reports of permanent vision loss with unapproved balanced salt solutions to a serious drop in blood pressure and increased heart rate from the topical papain products," said Janet Woodcock, director for the Center for Drug Evaluation and Research.
Unapproved topical papain products
Topical drug ointments containing papain are used to remove dead or contaminated tissue in acute and chronic lesions, such as diabetic ulcers, pressure ulcers, varicose ulcers, and traumatic infected wounds. Trade names for these products include Accuzyme, Allanfil, Allanzyme, Ethezyme, Gladase, Kovia, Panafil, Pap Urea, and Ziox. Other products are marketed under the names of the active ingredients, for instance, papain-urea ointment.
In 2008 the FDA announced its intention to take action against these products because it had received reports of serious adverse events in patients using products containing papain. Reports included hypersensitivity (allergic) reactions that lead to hypotension (low blood pressure) and tachycardia (rapid heart rate). In addition, people allergic to latex can also be allergic to papaya, the source of papain, implying that people with latex sensitivity may be at increased risk of suffering an adverse reaction to a topical papain drug product.
FDA recommended that people with concerns about using topical papain preparations contact their health care provider about discontinuing use.
Human cysteine proteases from papain family
See also
References
- ^ a b Islam MN, Molinar-Toribio EM (July–December 2013). "Development of a meat tenderizer based on papaya peel. Observación por Pares Basada en Mapas Conceptuales: Una Estrategia para Fomentar el "Scholarship of Teaching and Learning" en la Universidad Tecnológica de Panamá. 2013;24" (PDF). RIDTEC. 9 (2).
- ^ PMID 7845226.
- PMID 8439290.
- PMID 3117099.
- PMID 12188906.
- ^ "UniProt P00784: Papain precursor – Carica papaya (Papaya)". UniProtKB.
- PMID 2397208.
- PMID 19688822.
- ^ "Data Sheet - Papain". Archived from the original on 2014-07-15. Retrieved 2010-08-08.
- ^ "Papain - Selective Proteolytic Enzymes". Sigma-Aldrich. Retrieved 2 August 2020.
- ^ Maiti AK, Ahlawat SS, Sharma DP, Khanna N (2008). "Application of natural tenderizers in meat-a review" (PDF). Agricultural Reviews. 29 (3): 226–30.
- PMID 23493413.
- PMID 18477426.
- PMID 16105251.
- S2CID 102894814.
- PMID 23353003.
- PMID 18298830.
- ^ Shuren J (2008-09-22). "Topical Drug Products Containing Papain; Enforcement Action Dates" (PDF). United States Food and Drug Administration, Department of Health and Human Services. Archived from the original (PDF) on 1 March 2017.
External links
- The MEROPS online database for peptidases and their inhibitors: C01.001
- Papain at the U.S. National Library of Medicine Medical Subject Headings (MeSH)
- drugdigest- info on papin
- Papain Applications, Inhibitors and Substrates
- Data sheet-Papain from BIOZYM
- Papain on Proteopedia (wiki with more protein specific info)
- Overview of all the structural information available in the PDB for UniProt: P00784 (Papain) at the PDBe-KB.