What primary group does glutamine donate in transamination reactions?

In transamination reactions, amino acids undergo a process where they transfer their amino group to a keto acid, forming a new amino acid and a new keto acid in the process. Glutamine, specifically, is known for its amino group donation due to its structural characteristics.

Glutamine has an amide functional group attached to a side chain, where its reactive amino group (-NH2) can be readily transferred to an alpha-keto acid, usually converting it into another amino acid. This reaction is catalyzed by specific enzymes called aminotransferases or transaminases, which facilitate the transfer of the amino group from glutamine to the acceptor molecule.

This process is critical in amino acid metabolism and nitrogen assimilation, highlighting the central role of glutamine as a nitrogen donor in biosynthetic pathways. Thus, the correct answer reflects the fundamental biochemical function of glutamine in transamination reactions.