Chymotrypsin and Lysozyme are the most important enzymes. Mechanism of action of these enzymes and introduction of these enzyme are given in this presentation in simple, easy and understanding language. Hope you will find it useful :)

1. Mechanism of action of
Chymotrypsin & Lysozyme
VANSHIKA VARSHNEY
R210100249009
MSc BIOCHEMISTRY
1ST YEAR
CCS University, UP

2. What are Chymotrypsin & Lysozyme ??????
Chymotrypsin and lysozyme both are type of competitive inhibitor. Competitive inhibitor are
those, that binds to the active site and prevents the substrate from binding there.
Chymotrypsin competitively inhibit the activity of proteolytic enzymes. Protease inhibitors can
be anti-carcinogenic, antioxidative, blood glucose regulatory, as well as anti-inflammatory.
Lysozyme inhibitors effectively protect bacteria against lysozyme challenge and thus could
contribute to host colonization or infection. Furthermore, they can be anticipated to modulate
the host immune response by interfering with the release of PG fragments during infection.

3. CHYMOTRYPSIN
● Chymotrypsin is a digestive proteolytic enzyme produced by the
pancreas that is used in the small intestine to help digest proteins.
● The enzyme is also used to help create medicines and has been
used in clinical healthcare settings since the 1960s.
● AKA serine protease enzyme.
● Also known as A-Chymotrypsin, A-Chymotrypsine,
Chymotrypsinum, Quimotripsina
● Specific for peptide bonds adjacent to aromatic amino acid
residues (Trp, Phe, Tyr).
● It catalysed the hydrolytic cleavage of peptide bonds.

4. Properties
❏ Molecular weight : 25.6 D
❏ Optimal pH : 7.8-8.9
❏ Optimal Temperature : 40-50 ℃
❏ Isoelectric Point : 8.52 (Chymotrypsinogen, Theoretical)
❏ Extinction coefficient : 51,480 cm-1 M-1
❏ 247 amino acid residues.
❏ 3 peptide chains.
❏ 4 disulfide bridges
❏ 14% 𝜶 helix and 45% 𝜷 conformation.
❏ Catalytic triad - His57 & Ser195 located at substrate binding site along with
Asp102.

5. 1T8O
CRYSTAL
STRUCTURE OF THE
P1 TRP BPTI MUTANT-
BOVINE
CHYMOTRYPSIN
COMPLEX

10. LYSOZYME
● Discovered by Alexander Fleming in 1922.
● Lysozyme is well known as an antimicrobial enzyme N-acetylmuramide glycanhydrolase.
● It derives its name by hydrolysing the polymer consisting of alternating N-
acetylglucosamine (NAG) & N-acetylmuramic acid (NAM) units.
● Lysozyme are secreted abundantly in saliva, human milk, tears and occur widely in cells.
● Lysozyme is used to breakdown the bacterial cell wall.
● It is the classic example of competitive inhibitor.

11. Properties
❏ Molecular weight : 14-15 kD
❏ Optimal pH : 5-6
❏ Optimal Temperature : 20-30℃
❏ Isoelectric Point : 11
❏ Extinction coefficient : 68,000 cm-1 M-1
❏ 129 amino acid residues.
❏ 1 peptide chains.
❏ 4 disulfide bridges
❏ 31% 𝜶 helix and 65% 𝜷 conformation.
❏ Catalytic residues - Glu35 & Asp52 located at substrate binding site.

14. 2EPE
Crystal structure analysis of Hen
egg white lysozyme grown by
capillary method