Covalent Regulation of Glutamine Synthetase

The video explains the covalent regulation of glutamine synthetase, an enzyme that converts glutamate to glutamine. This regulation is crucial due to the enzyme's interaction with toxic ammonia. The enzyme is regulated by adenylation and deadenylation, controlled by adenyl transferase and uridyl transferase. High energy states activate glutamine synthetase, promoting biosynthesis, while low energy states favor catabolism. The video also highlights the role of P2 protein in this regulatory mechanism.

What is the primary function of glutamine synthetase?

• To synthesize ATP

• To degrade ammonia

• To convert glutamate to glutamine

• To convert glutamine to glutamate

How is glutamine synthetase inactivated?

• By acetylation

• By methylation

• By adenylylation

• By phosphorylation

What role does adenylyl transferase play in the regulation of glutamine synthetase?

• It adds an AMP group to glutamine synthetase

• It degrades glutamine synthetase

• It removes the AMP group from glutamine synthetase

• It phosphorylates glutamine synthetase

Which protein must be uridylated to activate glutamine synthetase?

• P4 protein

• P3 protein

• P2 protein

• P1 protein

What effect do high levels of ATP and alpha-ketoglutarate have on uridyl transferase?

• They activate uridyl transferase

• They inhibit uridyl transferase

• They degrade uridyl transferase

• They have no effect

What happens to glutamine synthetase when P2 is not uridylated?

• It becomes active

• It becomes inactive

• It is phosphorylated

• It is degraded

In a low energy state, what is the fate of glutamine?

• It is used for nucleic acid synthesis

• It is converted to glutamate

• It is synthesized into proteins

• It is stored as glycogen