This document discusses deamination and transamination processes in the liver and other tissues. Deamination is the removal of amino groups from amino acids, producing ammonia (NH3). There are two types - oxidative deamination which is coupled to other reactions, and non-oxidative deamination which directly produces NH3. Transamination is the transfer of amino groups between amino acids and keto acids, catalyzed by transaminase enzymes using pyridoxal phosphate as a cofactor. This allows for interconversion and redistribution of amino acids as well as the production of ketone bodies from amino acids for energy production. Both deamination and transamination play important roles in amino acid catabolism and anabolism.

1. Deamination and
transamination

2. INTRODUCTION
• Liver is the primary site of amino acid
metabolism, but other parts such as kidney,
small intestine, muscles and adipose tissue take
part.
• First step is removal of the amine group
• Transferred/removed by either
TRANSAMINATION or DEAMINATION.

3. WHAT IS TRANSAMINATION
• Transfer of amino group to keto acid
• Interconversion of a pair amino acid and keto
acids
• Catalysed by group of enzymes(transaminase)
•
• Pyridoxal 5' phosphate (PLP) and Pyridoxamine 5'
phosphate (PMP)
•
Reversible reaction

4. • Specific transaminases exist for each pair of amino and
keto acids
• NH3 is not liberated
• Reversible reaction
• Few amino acids do not go through transamination
• Not restricted to a-amino groups

5. SIGNIFICANCE OF TRANSAMINATION
• Involved in both catabolic and anabolic reactions.
• Resultant ɑ-keto acid can be completely oxidized to provide
energy, glucose, fats or ketone bodies
• Keto acid goes through complete metabolism into CO2 and
water in citric cycle
• Diverts excess amino acids toward energy generation
• Important for redistribution of amino groups and production of
non-essential amino acids

6. SIGNIFICANCE OF TRANSAMINATION
• Diverts excess amino acids toward energy generation
• Important for redistribution of amino groups and production of
non-essential amino acids

9. • What is DEAMINATIONandTRANS-
DEAMINATION?
+The removal of amino group from the amino
acids as NH3 is DEAMINATION.
+Transamination and deamination are
simultaneous processes often involving
glutamate as the central molecule , so this is
termed as TRANS-DEAMINATION.

10. PURPOSE :
+Deamination takes place in
the liver. It is the process by
which amino acids are broken
down if there is an excess
protein intake.
+This process allows the
system to convert excess
amino acids into usable
resources.

11. OXIDATIVE DEAMINATION :
Oxidative deamination is
the liberation of free
ammonia from the amino
group of amino acids
coupled with reactions .

12. NON- OXIDATIVE DEAMINATION:
Non-Oxidative deamination is the liberation of
ammonia from amino acids without
undergoing oxidation .
Minor pathways of deamination
[serine-threonine dehydratase]
serine ----> pyruvate + NH4+
threonine ----> alpha ketobutyrate + NH4+

13. Deamination in Ammonia
Deamination of amino acids, mainly serine and threonine, is catalyzed by
either serine dehydratase or threonine dehydratase (these enzymes may also
be referred to as Ser or Thr deaminase, Ser or Thr dehydratase, or Ser or Thr
ammonia lyase). These reactions are nonoxidative. The coenzyme for these
enzymes is pyridoxal phosphate (PLP) and the reactions catalyzed are:
L-serine -> pyruvate + NH3 and L-threonine->alpha- ketobutyrate +NH3
Both enzymes are classified as ammonia lyases.

14. Deamination in Urea
Liberation of ammonia is used for the synthesis of
urea cycle and carbon skeleton of amino acids is
converted to keto acids . It maybe either oxidative .
Both transamination and deamination involve in
using glutamate as central molecule .

15. Hope you might have
Learnt something new...