The document discusses enzyme specificity, outlining two types: absolute and broad specificity, with examples including fumarase and chymotrypsin. It explains the lock and key hypothesis in enzyme catalysis and the importance of enzyme active site mapping for drug design. The document emphasizes the functional and structural features of substrates and enzymes that contribute to their specificity.

1. Enzymology :Enzyme specificity-Types & applications
Dr. Rohini C Sane

2. Enzyme specificity
 Types of Enzyme specificity
1. Absolute
2. Broad
 Absolute Specificity of Enzymes
eg Fumarase & Aspartase exhibits rigid & geometrical
specificity

3. Absolute Specificity of Enzymes :

4. Enzyme specificity
• Absolute Specificity Of Enzymes
Fumarase dose not react with Maleate (cis isomers of Fumarate )

5. Enzyme specificity
Absolute specificity of enzymes
Aspartase dose not react with D-Aspartate ,OR Maleate –CIS isomer with FUMARATE

6. Enzyme specificity
Broad Specificity of enzymes
1. eg Chymotrypsin hydrolyses peptide bond (carboxyl group
contributed by phenylalanine, Tyrosine, Tryptophan)
2. Intestinal Phosphatase –hydrolysis of esters of phosphoric acid

7. Broad specificity of Chymotrypsin
Hydrolysis of peptide bonds by Chymotrypsin
• A1—A2-----------------------------A4 ----A5--COOH
• A1—A2-----------------------------A4 ----A5—COOH
• A1—A2-----------------------------A4 ----A5--COOH
• Site of cleavage by chymotrypsin
PHENYLALANINE
TYROSINE
TRYPTOPHAN

8. Broad specificity of Trypsin

9. Lock & Key hypothesis of enzyme specificity

10. Lock & Key hypothesis
of enzyme catalysis

11. Applications of Enzyme Specificity
1.Lock & key relationship between the substrate & specific area on
the enzyme
2.Substrate structural features
(a) bonding group or functional group
( b) susceptible bond
Enzyme structural features
(a) positioning site Active site
(b) catalytic site
 Mapping of enzyme active site-needed for drug designing

12. Mapping Of Enzyme Active Site
• Substrate of Chymotrypsin =
hydrophobic positioning group +
susceptible acyl bond
• Active site of Chymotrypsin
=positioning group + catalytic site
• Positioning group can be attributed
by hydrophobic /aromatic ring of
amide ,esters ,amino acids ( Phe
,Trp,Tyr )