Transamination is a reversible biochemical reaction pivotal in amino acid metabolism.
It facilitates the interconversion of amino acids and the synthesis of non-essential amino acids within the body.
This process is mediated by enzymes known as transaminases or aminotransferases, which rely on a cofactor, pyridoxal phosphate (PLP)—a vitamin B6 derivative, for activity.
The essence of transamination lies in transferring an amino group (-NH2) from an amino acid to an α-keto acid, thereby reshuffling amino groups among amino acids and α-keto acids.
Mechanism of Transamination
1) Amino Group Donation
An amino acid, referred to as Amino Acid 1, donates its amino group to the PLP cofactor, creating a Schiff base intermediate.
2) Amino Group Transfer
This amino group is transferred from the Schiff base to an α-keto acid. This results in the formation of a new amino acid, termed Amino Acid 2, while transforming the original amino acid into an α-keto acid.
3) Formation of New Compounds
Consequently, the amino group from Amino Acid 1 is relocated to an α-keto acid, yielding Amino Acid 2, and converting Amino Acid 1 into an α-keto acid.
Significance of Transamination
Transamination underpins several critical physiological functions. It is essential for:
Synthesizing non-essential amino acids.
Facilitating the interconversion of amino acids, which is crucial for metabolic adaptation.
Producing metabolic intermediates that are utilized in other pathways, such as gluconeogenesis and the citric acid cycle.
Clinical Relevance
The activity of transaminases is not only integral to normal metabolic processes but also serves as a biomarker for health conditions.
Aberrations in transaminase levels can indicate liver damage or specific metabolic disorders, making them important diagnostic markers.