Enzyme Inhibition

1. ENZYME INHIBITION
By-
Manish Sahu
M.Sc. Chemistry (Final)
Sp.- Physical Chemistry

2. SYNOPSIS
• INTRODUCTION
• ENZYME INHIBITION
• CLASSIFICASTION OF ENZYME INHIBITION
REVERSIBLE ENZYME INHIBITION
• MACHENISM OF REVERSIBLE ENZYME
INHIBITION
IRREVERSIBLE ENZYME INHIBITION
• CONCLUSION
• REFERENCES

3. INTRODUCTION
Enzyme are the substance that
increases the rate of a reaction .
Reactant bind to enzyme and
product are released .
E + S ES P

4.  Compound which convert the
enzyme into inactive substance .
 And thus adversely affect the rate
of enzymatically catalysed reaction .
 Inhibitors are substance that bind
to an enzyme and interfere in its
activity .
E + S + I ESI or EI
NO PRODUCT FORMATION
ENZYME INHIBITION

5. CLASSIFICATION OF ENZYME
INHIBITION
ENZYME INHIBITION
REVERSIBLE
ENZYME
INHIBITION
IRREVERSIBLE
ENZYME
INHIBITION
COMPETITIVE
NON-COMPETITTIVE
UN-COMPETITTIVE

6. REVERSIBLE ENZYME INHIBITION
 Reversible bind to enzyme through
Non-covalent bond .
 A reversible inhibitor dissociates
very rapidly from its target enzyme .
Depending on factors :-
 whether the inhibitor bind at
the active site or at allosteric site .
Whether the inhibitor bind either
with the free enzyme , Or with the enzyme
substrate complex , Or with either of two.

7. A] COMPETITIVE INHIBITION
 These comate with the substrate
molecule for the active site .
E.g. An enzyme succinic acid
dehydrogense catalyzed the
conversion of succinic acid
to fumaric acid .
The structure of the inhibitor (I)
closely resembles with that of the
substrate (S)

8. NH2

9. NON – COMETITIVE INHIBITION
No competition occurs between the
Substrate and the inhibitor .
Inhibitor bind at a site other than
the active sit of the enzyme .
I & S bind at different site formation
of both ES & ESI complex is possible.
Both EI & ESI may break down to
Produced the reaction product (P) .

10. I – bind only to the ES complex ,not
to free E .
There no EI complex , only E , ES and
ESI but ESI can’t make product .

11. COMPARE OF REVERSIBLE
ENZYME INHIBITION

12. - - -

13. IRREVERSIBLE ENZYME
INHIBITION
Inhibitor bind covalently ( strong)
with the enzyme irreversibly .
Irreversibly inhibitors occupy or
destroy the active sites of the
enzyme permanently and decrease
the reaction rate .
This inhibitors are usually toxic
substance .

14. CONCLUSION
It can be conclude that enzyme
inhibitor and activators that
modulate the velocity of enzymatic
reaction play an important role in the
regulation of metabolism .

15. REFERENCES

16. THANK YOU