Which amino acid is considered the rate-limiting precursor for the synthesis of nitric oxide via the arginine-citrulline pathway?

A Glutamine
B Arginine ✓
C Citrulline
D Ornithine

Explanation

Arginine is the primary precursor for the synthesis of nitric oxide, a key signaling molecule involved in many physiological processes.

Mnemonic

'Arg' = 'argument' for nitric oxide synthesis

Source

Berg et al., Biochemistry
Protein Metabolism Biochemistry Amino Acid Metabolism Hard MEDICAL Confidence: high