[{"from": "human", "value": "Could you give me a brief overview of this molecule? [C][Branch1][O][C][C@@H1][Branch1][=Branch1][C][=Branch1][C][=O][O][N][C][N][C][=Branch1][C][=O][N]"}, {"from": "gpt", "value": "The molecule is a non-essential amino acid. In hepatocytes, L-citrulline is synthesized in the urea cycle by the addition of carbon dioxide and ammonia to ornithine. L-citrulline is converted into L-arginine by the enzymes argininosuccinate synthetase and argininosuccinate lyase in the presence of L-aspartate and ATP. Subsequently, L-arginine is converted to nitric oxide by nitric oxide synthase and L-citrulline is regenerated as a by-product."}]