Arginine attenuator peptide (AAP) that has a regulatory role in the production of arginine-specific carbamoyl phosphate synthetase. Encoded by an upstream open reading frame (uORF) within the 5'-leader region of arginine-specific carbamoyl phosphate synthetase small chain (CPA1) mRNA, it attenuates the translation of the downstream CPA1 ORF. In the presence of high concentrations of arginine, ribosomes translating the uORF encoding AAP stall at the termination codon, resulting in reduced translation from the downstream CPA1 initiation codon. Belongs to the arginine attenuator peptide family.