All Photos(2)



Papain from papaya latex

lyophilized powder, aseptically filled

CAS Number:
Enzyme Commission number:
EC Number:
MDL number:

biological source

papaya (latex)

Quality Level


aseptically filled


lyophilized powder

specific activity

≥8.0 units/mg protein

mol wt

23.4 kDa


H2O: soluble 1.2 mg/mL

storage temp.


Looking for similar products? Visit Product Comparison Guide

Related Categories

General description

Papain is a thermostable enzyme and becomes inactive at 55°C. It has two domains and the catalytic region is present at the domain interface. The cysteine 25 in the active site performs the proteolysis by nucleophilic attack on the carbonyl carbon of a peptides. Papain has wide industrial applications in food and pharmaceutical industry.


Papain is used in dissecting solutions. It is used to produce Fab fragments of antibodies . It is used for cell dissociation since it has been shown to be more effective and less damaging with certain tissues. Papain has been used to isolate morphologically intact cortical neurons from postnatal rats. Limited papain digestion is used for structural studies of enzymes and other proteins. In addition, papain is used in red cell serology to modify the red cell surface to enhance or destroy the reactivity of many red cell antigens. Papain is useful for platelet serology studies. Papain has also been used in the enzymatic synthesis of amino acids, peptides, and other molecules. Product P5306 is provided as a lyophilized powder that is aseptically filled. It has been used to digest mouse retinas to study the RAGE axis in nonproliferative diabetic retinopathy (NPDR).
The product from Sigma has been used in the digestion of extracellular matrix (ECM). It has also been used with other proteolytic enzymes for in situ protein degradation to produce crystals suitable for structure determination.
Used to produce Fab fragments of antibodies. Also used for cell dissociation since it has been shown to be more effective and less damaging with certain tissues.

Biochem/physiol Actions

Papain papaya latex has antifungal activity against C. albicans. Papain consists of a single polypeptide chain with three disulfide bridges and a sulfhydryl group necessary for activity of the enzyme.
A cysteine protease that cleaves peptide bonds of basic amino acids, leucine, or glycine.
pH optimum 6.0-7.0
Also hydrolyzes esters and amides.

Unit Definition

One unit will hydrolyze 1.0 μmole of BAEE per minute at pH 6.2 at 25 deg C.

Preparation Note

Prepared from P 4762

Other Notes

View more information on papain at


Exclamation markHealth hazard

Signal Word


Hazard Statements

Precautionary Statements

Hazard Classifications

Eye Irrit. 2 - Resp. Sens. 1 - Skin Irrit. 2 - STOT SE 3

Target Organs

Respiratory system

Storage Class Code

11 - Combustible Solids



Flash Point(F)

Not applicable

Flash Point(C)

Not applicable

Personal Protective Equipment

dust mask type N95 (US), Eyeshields, Gloves

Certificate of Analysis

Enter Lot Number to search for Certificate of Analysis (COA).

Certificate of Origin

Enter Lot Number to search for Certificate of Origin (COO).

Technical Information

More Documents


Our team of scientists has experience in all areas of research including Life Science, Material Science, Chemical Synthesis, Chromatography, Analytical and many others.

Contact Technical Service