title: Interaction of N-ethyl-N'-nitro-n-nitrosoguanidine with nucleic acids and proteins in comparison with N-methyl-N'-nitro-N-nitrosoguanidine.
abstract: Reactivity of N-ethyl-N'-nitro-N-nitrosoguanidine (ENNG) was studied in comparison with N-methyl-N'-nitro-N-nitrosoguanidine (MNNG). The radioactivity of [guanidino-14C]-ENNG was incorporated only into the protein fraction and that of [ethyl-14C]ENNG was incorporated into DNA, RNA and protein fractions in ascites hepatoma AH7974 cells, as were those of [guanidino-14C]- and [methyl-14C]MNNG, respectively. The amounts of the binding of ENNG were less than those of MNNG, especially in the corporation of the ethyl moiety of ENNG into nucleic acid fractions. In a non-cellular system, the radioactivity of [guanidino-14C]ENNG was incorporated into proteins, preferentially into basic proteins such as cytochrome c, but was not incorporated into nucleic acids. This behavior is similar to that of [guanidino-14C]MNNG, while the amount of binding of the former was about half of that of the latter. The radioactivity of [ethyl-14C]ENNG was also incorporated into basic proteins to almost the same extent as that of [methyl-14C]MNNG. However, the binding of the ethyl moiety of ENNG to nucleic acids was much lower than that of the methyl moiety of MNNG. Horse heart cytochrome c, bovine pancreatic RNase A and regenerating rat liver chromatin had altered their biological activities to various degrees after modification by ENNG or MNNG.
mesh_terms: D000818:Animals; D002417:Cattle; D002460:Cell Line; D003574:Cytochrome c Group / Q000378:metabolism; D004247:DNA / Q000378:metabolism; D004720:Endonucleases / Q000378:metabolism; D006736:Horses; D008114:Liver Neoplasms, Experimental / Q000378:metabolism*; D008297:Male; D008769:Methylnitronitrosoguanidine / Q000031:analogs & derivatives* / Q000378:metabolism*; D009696:Nucleic Acids / Q000378:metabolism*; D011506:Proteins / Q000378:metabolism*; D012313:RNA / Q000378:metabolism; D051381:Rats; D012259:Ribonuclease, Pancreatic; D012260:Ribonucleases / Q000378:metabolism
chemical_list: D003574:Cytochrome c Group; D009696:Nucleic Acids; D011506:Proteins; D008769:Methylnitronitrosoguanidine; C013525:ENNG; D012313:RNA; D004247:DNA; D004720:Endonucleases; D012260:Ribonucleases; D012259:Ribonuclease, Pancreatic