Activation of carcinogenic arylhydroxamic acids by human tissues

Incubation of the carcinogenic arylhydroxamic acids N-hydroxy-N-2-fluorenylacetamide or N-hydroxy-N-4-biphenylacetamide and tRNA with 105,000 times g supernatants of homogenates of human small intestine, liver, or colon led to formation of arylamine-substituted nucleic acid adducts. These data indicated that enzymes of human tissues could activate arylhydroxamic acids by N leads to O acyl transfer. The unstable N-acetoxyarylamines formed by these enzymes reacted spontaneously with the tRNA to give covalently linked adducts with the nucleic acid.