N-acetyl glutamate

The rate of urea formation is mainly controlled by reaction [1]. N-acetyl glutamate, as an allosteric effector, activates carbamoyl-phosphate synthase. In turn, the concentration of acetyl glutamate depends on arginine and ATP levels, as well as other factors. 

Regulators Activator N-acetyl- glutamate Inhibitor UTP Activator ATPiWfi ... 

Relative decrease in N-acetyl aspartate, N-acetyl glutamate, creatine... 

Lund, R, and Wiggins, D. (1984). Is N-acetyl-glutamate a short-term regulator of urea synthesis Biochem J. 218, 991-994. 

Synonyms L-N-Acetylglutamic acid N-Acetylglutamic acid N-Acetyl-L-glutamic acid L-Glutamic acid, N-acetyl- Glutamic acid, N-acetyl-, L-... 

The precursor for ornithine synthesis is N-acetylglutamate, which is also an obligatory activator of carbamyl phosphate synthetase. This provides a regulatory mechanism — if N-acetylglutamate is not available for ornithine synthesis (and hence there would be impaired activity of the urea synthesis cycle), then ammonium is not incorporated into carbamyl phosphate. This can be a cause of hyperammonaemia in a variety of metabolic disturbances that lead to either a lack of acetyl CoA for N-acetyl glutamate synthesis or an accumulation of propionyl CoA, which is a poor substrate for, and hence an inhibitor of, N-acetylglutamate synthetase. 

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