Which process is NOT directly linked to the action of glutamine synthetase?

Glutamine synthetase is an important enzyme primarily involved in the assimilation of ammonia into the amino acid glutamine, which plays a critical role in nitrogen metabolism and various biosynthetic pathways. The enzyme catalyzes the reaction where ammonia and glutamate are converted into glutamine, allowing for the safe transport and incorporation of nitrogen into organic molecules.

The processes directly linked to the action of glutamine synthetase include:

• Ammonia assimilation: This is the primary function of glutamine synthetase, as it helps incorporate free ammonia into biological systems by forming glutamine.

• Nucleotide synthesis: Glutamine is a key nitrogen source for the synthesis of nucleotides, which are essential components of DNA and RNA. The transfer of nitrogen from glutamine is utilized in the biosynthesis of purines and pyrimidines.

• Detoxification of excess nitrogen: Excess ammonia can be toxic to cells, and glutamine synthetase helps convert ammonia into glutamine, thereby detoxifying it and facilitating safer nitrogen handling in metabolic processes.

In contrast, ketogenesis is the metabolic pathway that produces ketone bodies from fatty acids and occurs primarily in the liver during periods of low carbohydrate availability. It does not directly involve glutamine synthetase nor