This document discusses various proteolytic enzymes, including their sources and applications. It describes proteases such as papain from papaya, used as a meat tenderizer, and bromelain from pineapple, also used for meat tenderizing. Pepsin from the stomach aids protein digestion. Rennin produces curdling in milk. Trypsin and cathepsins break down proteins, with trypsin used in cell culture and proteomics. These enzymes degrade proteins through hydrolysis of peptide bonds.

1. Proteolytic EnzymesProteolytic Enzymes
Prof. Harshraj. S. Shinde
K. K. Wagh College of Agril. Biotech, Nashik. India

2. Proteolytic EnzymesProteolytic Enzymes
Enzymes involved in degradation of proteins are
called as proteases or proteolytic enzymes
Industrially available proteolytic enzymes
produced by microorganisms are usually
mixtures of endopeptidases and exopeptidases.
Proteins Polypeptides
Polypeptides amino acids
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Endopeptidases
Exopeptidases

3. Cont …Cont …
 Because of the complex structures and high molecular
weights of proteins enzymic proteolysis is extremely
complicated.
 Most proteases are quite specific with regard to which
peptide linkages they can split
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4. List of proteolytic enzymesList of proteolytic enzymes
a. Papain
b. Ficain
c. Bromelain
d. Pepsin
e. Rennin
f. Cathepsin
g. Trypsin
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5. A) Papain
◦ Found in papaya
◦ papain, also known as papaya proteinase I
◦ Broad pH (3-11) and temperature stability
 For this reason very popular for a variety of food
applications.
1. Used as a meat tenderizer on inferior meat cuts (can also use slice
of pineapple on meat)
 The enzyme makes its way into the muscle and hydrolyzes
primarily connective tissue proteins (collagen etc.) and
softens muscle
 Have to use low amount to prevent liquefaction of muscle
 If you mix raw papaya into Jell-O it will not form a gel

6. Application of papainApplication of papain
MeatTenderizer- Papain ( a protease
found in papaya) is used as meat
tenderizer to soften meat for cooking

7. Cont…Cont…
Papain can be used to dissociate cells in
the first step of cell culture preparations.
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8. FicainFicain
Ficain also known as
ficin is an enzyme that is derived from figs latex
It is of a family of proteases known as
the cysteine endopeptidases
It is one of the most commonly used for
differentiating many blood group antigens
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9. BromelainBromelain
 Bromelain is an enzyme generally found in the stems
and fruits of pineapples.
 According their sources enzymes are divided into
A. Stem bromelain.
B. Fruit bromelain.
 The proteolytic enzymes are sulfhydryl proteases, since
a free sulfhydryl group of a cysteine side chain is
required for function
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10. Bromelain is present in all parts of the
pineapple plant but the stem is the most
common commercial source
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11. Applications of bromelainApplications of bromelain
 Along with papain, bromelain is one of the most popular
proteases to use for meat tenderizinguse for meat tenderizing
 Cooked pineapple does not have a tenderizing effect, as
the enzymes are heat-labile
 Preparation of meat ballsPreparation of meat balls
 Systemic enzyme therapy (combinations of proteolytic
enzymes such as bromelain, trypsin and papain) has
been used in the treatment of breast cancertreatment of breast cancer
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12. PepsinPepsin
 Pepsin is an enzyme whose zymogen (pepsinogen) is released by
the chief cellschief cells in the stomach and that degrades
food proteins into peptides
 It was discovered by Theodor Schwann who also coined its name
from the Greek word pepsis, meaning "digestion
 Pepsin is one of three principal protein-degrading enzyme in the
digestive system, the other two being chymotrypsin and trypsin
 Pepsin is most efficient in cleaving peptide bonds and
preferably breaks at aromatic amino acids such
as phenylalanine, tryptophan, and tyrosine
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13. Cont…Cont…
 Pepsin is most active in acidic environments Pepsin exhibits
maximal activity at pH 2.0 and is inactive at pH 6.5
 In most cases Pepsinogen is activated by HCl
 Pepsins should be stored at very low temperatures (between
80 °C and 20 °C) to prevent autolysis (self-digestion− −
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14. Applications of pepsinApplications of pepsin
Pepsin is commonly used in the
preparation of F(ab')2 fragments from
antibodies
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15. Cont…Cont…
Powder of pepsin is often used as a
dietary supplement to aid digestion
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16. RenninRennin
 Rennin or Chymosin is a protease produced by
newborn ruminant in the fourth stomach to curdle the milk they
ingest
 The native substrate of Chymosin is K-casein cleavaes at amino
acids like phenylalanine and methionine
 Bovine chymosin is now produced recombinantly in E.
coli, Aspergillus niger alternative resource.
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17. Application of renninApplication of rennin
It is widely used in the production
of cheese
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18. CathepsinCathepsin
 Cathepsins are proteases that degrade proteins) found
in all animals as well as other organisms.
 Enzyme cathepsins found only in the lysosome
 Most of the members become activated at the low pH
found in lysosomes
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19. Cont….Cont….
There are approximately a dozen members of
this family, which are distinguished by their
structure
 Cathepsin A (serine protease)
 Cathepsin B (cysteine protease)
 Cathepsin C (cysteine protease)
 Cathepsin D (aspartyl protease)
 Cathepsin E (aspartyl protease)
 Cathepsin F (cysteine proteinase)
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20. TrypsinTrypsin
 Trypsin is a protease found in the digestive system of
many vertebrates, where it hydrolyses proteins.
 Trypsin is produced in the pancreas as the inactive
protease trypsinogen.
 Trypsin cleaves peptide chains mainly at
the carboxyl side of the amino acids lysine or arginine
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21. Application of trypsinApplication of trypsin
 In a Animal tissue culture lab, trypsin is used to re-
suspend cells adherent to the cell culture dish wall
during the process of harvesting cells
 Used in proteomics experiments to digest proteins into
peptides for mass spectrometry analysis
 As a baking enzyme to improve the workability of
dough;
 in the extraction of seasonings and flavourings from
vegetable or animal proteins and in the manufacture of
sauces 21

22. Cont…Cont…
To improve the texture of fish products
To tenderize meat along with papain
For cold stabilization of beer
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23. Cont…Cont…
 In the production of hypoallergenic food where trypsin
break down specific allergenic proteins into non
allergenic peptides
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