It represents the enzyme lysozyme with its structure and its mechanism of action on the components of the cell layers.

2. Introduction
 Lysozyme is also called as muramidase or
N-acetylmuramide glycohydrolase.
 It is antimicrobial enzyme and small
globular protein, and present in tears,
nasal mucous, gastric secretion, milk and
egg white.
 It lyse the bacterial cell wall.
 Turn over no. : 0.5/sec. and E.C. no is
3.2.1.17
 In 1922, Alexander Fleming coined the
term lysozyme.

3. Structure of Lysozyme
 In 1965, David Phillips and his
colleague’s determined 3D structure by X-
ray crystallography.
 Molecular weight : 14.3 Kda
 Shape is ellipsoidal and dimension are
45X30X30 Ao
 It contain polypeptide chain of 129 amino
acid
 Lysin at the N terminal and Leucine at the
C terminal.

5. Structure of Lysozyme
 Active site of lysozyme are of six subunit
which are bind to six substrate molecules.

6. MECHANISM OF ACTION OF
LYSOZYME
Glutamate-35 and Aspartate-52 are
present at active site. After binding, D
residue is distorted half-chair conformation.
 Glu-35 transfer its proton to oxygen and
break the bond and generate carbonium
ion.
 Asp-52 stablize that ion , E ring will
released.
 Followed by addition of water, enzyme will
regenerated and ring D will be released.

8. Effect of pH on mechanism of
Lysozyme