Competitive Inhibition and various competitive inhibitors... There role related to human body and stuffs... Mechanisms of there action... Various DRUGS working via these stuffs... LINEWEAVER-BURK PLOT Applications Of Competitive Inhibition Sulphonamides Methotrexate Dicoumarol Isonicotinic acid hydrazide Alcohol dehydrogenase Statin Allopurinol Captopril THERE'S SOME ANIMATIONS TOO... IN BETWEEN FOR BETTER UNDERSTANDING... BUT IT AIN'T WORK FOR YA'LL... GUESS SO...

1. HEY! That’s
MY enzyme
Whatever. Don’t see
Your name on it.
INDRANI SAHA
DARAKSHA SAJID KHAN
FARHAJ SULTANA
BIKRANT ROY
COMPETITIVE INHIBITION

2. INTRODUCTION
We are here to highlight the majestic impact of Competitive
Inhibition which has given the world innumerable life saving
drugs.
Most antibiotics are based on the principles of Competitive
Inhibition.
Drugs against cancer and other deadly diseases utilize the
mechanisms of Competitive Inhibition.

3. DEFINITION:
The type of inhibition where the inhibitor is structural analogue of
substrate and it binds reversibly to the same site that substrate will
occupy normally, is called Competitive Inhibition.
EFFECT ON Vmax :
Vmax remains unchanged
EFFECT ON Km:
Km is increased
In presence of a competitive inhibitor more substrate is needed to
reach ½Vmax.
Competitive Inhibition

4.  The plots of the inhibited and uninhibited reactions intersect on
the y- axis at 1/Vmax. The inhibited and uninhibited reactions
show different X-axis intercepts, indicating that the apparent Km is
increased in the presence of the competitive inhibitor because -
1/Km moves closer to zero from a negative value.

5. Competitive Inhibition

7. EP

9. SUBSTRATES
INHIBITORS
ENZYMES
COMPETITIVE
INHIBITION
IN BETWEEN

10. Applications of Competitive
Inhibition
It has helped in the manufacture of innumerable life saving drugs.
Sulphonamides
Methotrexate
Dicoumarol
Isonicotinic acid hydrazide
Alcohol dehydrogenase
Statin
Allopurinol
Captopril

11. SULPHONAMIDES
Bacteria synthesize tetra
hydro folic acid by
combining Para amino
benzoic acid with pteroyl
glutamic acid.
Sulpha drugs are
structural analogs of Para
amino benzoic acid.
Enzyme dihydro
pteroate synthetase is
inhibited.
All sulpha drugs are
bacteriostatic.

12. METHOTREXATE
It inhibits Dihydrofolate reductase enzyme.
It is a structural analog of folic acid.
This is essential for DNA synthesis and cell
division.
It is used as an anticancer drug.

13. ALCOHOL DEHYDROGENASE
In methanol poisoning, methanol is acted upon by alcohol
dehydrogenase.
It is converted to formic acid which leads to toxicity.
This leads to metabolic acidosis, retinal oedema, COMA and death.
For treatment ethanol is used as it can competitively bind to alcohol
dehydrogenase.

14. CASE STUDY : METHANOL POISONING
•Doctors at a Vietnam hospital pumped 5 litres of beer into 48 year old
Nyugen Van Nhat’s stomach to save him from dying of alcohol poisoning.
•Doctors decided to take the step after the methanol level in his blood
was found 1,119 times higher than normal.
•The beer(ethanol) slowed down his liver’s methanol processing.
•Competitive inhibition provides a novel technique to combat alcohol
with alcohol.

15. STATIN
Statins lower
cholesterol levels by
inhibiting HMG CoA
reductase.
Statins can lower LDL
cholesterol by 70 mg/dl.
This leads to an
estimated 60% decrease
in cardiac events.
17% reduced risk of
stroke.

16. ALLOPURINOL
Allopurinol inhibits xanthine
oxidase .
Xanthine oxidase catalyzes the
oxidation of hypoxanthine to
xanthine .
It further catalyzes the oxidation
of xanthine to uric acid.
Allopurinol blocks the production
of uric acid in the body.
It is, therefore, used in the
treatment for gout.

17. ISONICOTINIC ACID HYDRAZIDE
It inhibits Beta ketoacyl carrier protein reductase
which is involved in elongation of mycolic acid.
It results in the inhibition of cell wall leading to
cell death.
It is an anti tuberculosis drug.

18. ANGIOTENSIN CONVERTING ENZYME
INHIBITORS
ACE inhibitors prevent the conversion of Angiotensin I to Angiotensin
II.
They inhibit the Angiotensin Converting Enzyme.
Angiotensin II is a potent vasoconstrictor.
Drugs like Captopril, Enalapril, Lisinopril, Ramipril and Fosinopril are
ACE inhibitors.
They are used in hypertension acute myocardial infarction.

19. DICOUMAROL
Dicoumarol is a competitive inhibitor of Vitamin K epoxide
reductase.
It inhibits Vitamin K recycling and causes depletion of active
Vitamin K in blood.
Thus, it acts as an anticoagulant.

20. CONCLUSION
•Competitive Inhibition has profound applications
in the field of medicine.
•Hence Competitive Inhibition is a boon to
mankind.
•So as medicos it is our responsibility to explore the
principles the Competitive Inhibition further and
exploit its potential.

21. THANK YOU