| http://www.reactome.org/bio... | biopax3:comment | Xenobiotics that contain either a carboxylic group or an aromatic hydroxylamine group are possible substrates for amino acid conjugation. Xenobiotics with a <i>carboxylic group</i> conjugate with an <i>amino group</i> of amino acids such as glycine, taurine and glutamine. The <i>hydroxylamine group</i> conjugates with the <i>carboxylic group</i> of amino acids such as proline and serine. The amino acid is first activated by an aminoacyl-tRNA-synthetase which then reacts with the hydroxylamine group to form a reactive N-ester. N-esters can degrade to form electrophilic nitrenium (R-N<sup>+</sup>-R') and carbonium (R-C<sup>+</sup>H<sub>2</sub>) ions. The pyrolysis product of tryptophan, an N-hydroxy intermediate, can potentially form these reactive electrophilic ions. | lld:biopax3 |
