In the body, aspirin (acetylsalicylic acid) is hydrolyzed to salicylate (ST). ST can then be hydroxylated to yield gentisic acid, conjugated with glucuronate, or conjugated with glycine to yield molecules that are excreted by the kidneys. The third of these conjugation processes is annotated here. It is the major route of ST catabolism and accounts for 20–65% of the products (Hutt et al, 1986). The conjugation proceeds in two steps. First, ST and ATP react with coenzyme A to form salicylate-CoA (ST-CoA), AMP, and pyrophosphate in a reaction catalyzed by xenobiotic/medium-chain fatty acid:CoA ligase (Vessey et al. 2003). Second, ST-CoA and glycine react to form salicyluric acid and Coenzyme A (Mawal and Qureshi 1994).