TRANSDEAMINATION AND
DEAMINATION
By:
Minhaz Ahmed
BBI11014
Int msc V sem
Tezpur university
Assam
CONTENT
• TRANSDEAMINATION
• TRANSAMINATION
• DEAMINATION
TRANSDEAMINATION
The amino group of amino acids is released by a
coupled reaction, TRANSDEAMINATION
Transamination followed by oxidative deamination.
Transamination takes place in the cytoplasm of all
the cells of the body : the amino group is transported
to liver as glutamic acid, which is finally oxidatively
deaminated in the mitochondria of hepatocytes.
Thus, the two components of the reaction are
physically far away, but phisiologically they are
coupled. Hence, Transdeamination.
• Transamination is a chemical reaction between two
molecules.
• One is an amino acid, which contains an amine (NH2)
group.
• The other is a keto acid, which contains a keto (=O)
group.
• In transamination, the NH2 group on one molecule is
exchanged with the =O group on the other molecule. The
amino acid becomes a keto acid, and the keto acid
becomes an amino acid.
• Transamination in biochemistry is accomplished by
enzymes called transaminases or aminotransferases.
5
Transamination
transfer of -NH2 group from one substrate to other
• most AA (not Lys, Thr, Pro, His, Trp, Arg, Met)
• amino group is transferred from AA to 2-oxoglutarate
• cofactor – pyridoxal phosphate (→ Schiff bases)
• reversible reaction ⇒ important for synthesis of AA
6
General scheme of transamination
CH2CH2COOH
O
CHOOC+R CH
NH2
COOH
aminokyselina 2-oxoglutarát
HOOC CH CH2CH2COOH
NH2
+R C
O
COOH
glutamát2-oxokyselina
aminotransferasa
pyridoxalfosfát
amino acid
2-oxo acid
2-oxoglutarate
glutamate
aminotransferase
pyridoxal phosphate
DEAMINATION
• Deamination is the removal of an amine group from
a molecule. Enzymes which catalyse this reaction are
called deaminases.
• In the human body, deamination takes place
primarily in the liver, however glutamate is also
deaminated in the kidneys.
• Deamination is the process by which amino acids are
broken down if there is an excess of protein intake.
The amino group is removed from the amino acid
and converted to ammonia.
Deamination of amino acids
•Deamination - elimination of amino group
from amino acid with ammonia formation.
• Four types of deamination:
• - oxidative (the most important for higher
animals),
• - reduction,
• - hydrolytic, and
• - intramolecular
Reduction deamination:
R-CH(NH2)-COOH + 2H+
→ R-CH2-COOH + NH3
amino acid fatty acid
Hydrolytic deamination:
R-CH(NH2)-COOH + H2O → R-CH(OH)-COOH +
NH3
amino acid hydroxyacid
Intramolecular deamination:
R-CH(NH2)-COOH → R-CH-CH-COOH + NH3
amino acid unsaturated fatty acid
 During oxidative deamination, an amino acid is 
converted into the corresponding keto acid by the 
removal of the amine functional group as ammonia.
 The amine functional group is replaced by the ketone 
group. The ammonia eventually goes into the urea 
cycle.
 Oxidative deamination occurs primarily on glutamic 
acid because glutamic acid was the end product of 
many transamination reactions.
 The glutamate dehydrogenase is controlled by ATP and 
ADP. ATP acts as an inhibitor whereas ADP is an 
activator.
12
Proteins
NH3
glutamate
glutamate + urea
(excretion by urine)
2-oxoglutarate +
glutamine
proteolysis
dehydrogenation + deamination
detoxication in liver
deamidation
in kidney
amino acids
transamination
detoxication
in other tissues
NH4
+
(excretion by urine)
NH4
+
(excretion by urine)
deamination
in kidney
Intake, catabolism, and excretion of nitrogen
THANK YOU

TRANSDEAMINATION AND DEAMINATION

  • 1.
  • 2.
  • 3.
    TRANSDEAMINATION The amino groupof amino acids is released by a coupled reaction, TRANSDEAMINATION Transamination followed by oxidative deamination. Transamination takes place in the cytoplasm of all the cells of the body : the amino group is transported to liver as glutamic acid, which is finally oxidatively deaminated in the mitochondria of hepatocytes. Thus, the two components of the reaction are physically far away, but phisiologically they are coupled. Hence, Transdeamination.
  • 4.
    • Transamination isa chemical reaction between two molecules. • One is an amino acid, which contains an amine (NH2) group. • The other is a keto acid, which contains a keto (=O) group. • In transamination, the NH2 group on one molecule is exchanged with the =O group on the other molecule. The amino acid becomes a keto acid, and the keto acid becomes an amino acid. • Transamination in biochemistry is accomplished by enzymes called transaminases or aminotransferases.
  • 5.
    5 Transamination transfer of -NH2group from one substrate to other • most AA (not Lys, Thr, Pro, His, Trp, Arg, Met) • amino group is transferred from AA to 2-oxoglutarate • cofactor – pyridoxal phosphate (→ Schiff bases) • reversible reaction ⇒ important for synthesis of AA
  • 6.
    6 General scheme oftransamination CH2CH2COOH O CHOOC+R CH NH2 COOH aminokyselina 2-oxoglutarát HOOC CH CH2CH2COOH NH2 +R C O COOH glutamát2-oxokyselina aminotransferasa pyridoxalfosfát amino acid 2-oxo acid 2-oxoglutarate glutamate aminotransferase pyridoxal phosphate
  • 7.
    DEAMINATION • Deamination isthe removal of an amine group from a molecule. Enzymes which catalyse this reaction are called deaminases. • In the human body, deamination takes place primarily in the liver, however glutamate is also deaminated in the kidneys. • Deamination is the process by which amino acids are broken down if there is an excess of protein intake. The amino group is removed from the amino acid and converted to ammonia.
  • 8.
    Deamination of aminoacids •Deamination - elimination of amino group from amino acid with ammonia formation. • Four types of deamination: • - oxidative (the most important for higher animals), • - reduction, • - hydrolytic, and • - intramolecular
  • 9.
    Reduction deamination: R-CH(NH2)-COOH +2H+ → R-CH2-COOH + NH3 amino acid fatty acid Hydrolytic deamination: R-CH(NH2)-COOH + H2O → R-CH(OH)-COOH + NH3 amino acid hydroxyacid Intramolecular deamination: R-CH(NH2)-COOH → R-CH-CH-COOH + NH3 amino acid unsaturated fatty acid
  • 10.
     During oxidative deamination, an amino acid is  converted into the corresponding keto acid by the  removal of the amine functional group as ammonia. The amine functional group is replaced by the ketone  group. The ammonia eventually goes into the urea  cycle.  Oxidative deamination occurs primarily on glutamic  acid because glutamic acid was the end product of  many transamination reactions.  The glutamate dehydrogenase is controlled by ATP and  ADP. ATP acts as an inhibitor whereas ADP is an  activator.
  • 12.
    12 Proteins NH3 glutamate glutamate + urea (excretionby urine) 2-oxoglutarate + glutamine proteolysis dehydrogenation + deamination detoxication in liver deamidation in kidney amino acids transamination detoxication in other tissues NH4 + (excretion by urine) NH4 + (excretion by urine) deamination in kidney Intake, catabolism, and excretion of nitrogen
  • 13.