Reactions of methylnitrosourea, epichlorohydrin, styrene oxide and acetoxyacetylaminofluorene with polyamino acids

Radioactive methylnitrosourea, epichlorohydrin, styrene oxide, and N-acetoxy-2-acetylaminofluorene were reacted with 14 different polyamino acids in vitro, to determine the relative reactivity of the functional groups in amino acids. All the carcinogens reacted preferentially with polycysteine and much less with polyhistidine. Reaction was also noted with polylysine, polymethionine and polyarginine, as well as with DNA. Epichlorohydrin and styrene oxide reacted also with polyserine. Methylnitrosourea and N-acetoxy-2-acetylamino-fluorene reacted relatively more with polyhistidine as compared with the epoxides. Polycysteine, polyhistidine and polylysine were more reactive towards styrene oxide at pH 8 than at pH 6.