What is indicated by the feedback inhibition of glutamine synthetase as tryptophan concentration increases?

What is indicated by the feedback inhibition of glutamine synthetase as tryptophan concentration increases?

• A. Translational control
• B. Glutamine degradation
• C. Transcriptional control
• D. Feedback inhibition

Answer: (D)

Feedback inhibition refers to a regulatory mechanism in which the accumulation of an end product inhibits an earlier step in the metabolic pathway, effectively preventing overproduction when sufficient amounts of that product are available. In this case, the increase of tryptophan concentration serves as a signal for feedback inhibition of glutamine synthetase. When the concentration of tryptophan rises, it indicates that there is an abundant supply of this amino acid. To maintain homeostasis and prevent the overproduction of tryptophan, the activity of glutamine synthetase is inhibited. This inhibition acts at the enzyme level, directly affecting its catalytic functionality and reducing the produced levels of glutamine, an important nitrogen donor in various biosynthetic pathways, including that of tryptophan itself. Understanding this process highlights the importance of maintaining balance in metabolic pathways, ensuring that resources are used efficiently and that excess intermediates do not accumulate.

Feedback inhibition refers to a regulatory mechanism in which the accumulation of an end product inhibits an earlier step in the metabolic pathway, effectively preventing overproduction when sufficient amounts of that product are available. In this case, the increase of tryptophan concentration serves as a signal for feedback inhibition of glutamine synthetase.

When the concentration of tryptophan rises, it indicates that there is an abundant supply of this amino acid. To maintain homeostasis and prevent the overproduction of tryptophan, the activity of glutamine synthetase is inhibited. This inhibition acts at the enzyme level, directly affecting its catalytic functionality and reducing the produced levels of glutamine, an important nitrogen donor in various biosynthetic pathways, including that of tryptophan itself.

Understanding this process highlights the importance of maintaining balance in metabolic pathways, ensuring that resources are used efficiently and that excess intermediates do not accumulate.