Mutagenicity of sodium azide and its metabolite azidoalanine in Drosophilamelanogaster

The mutagenic and toxic activities of sodium azide (NaN3) and its organic m etabolite L-azidoalanine [N-3-CH2-CH(NH)(2)-COOH] were examined in the diff erent stages of spermatogenesis in Drosophila melanogaster. Both azide and azidoalanine were toxic to the injected males, but azidoalanine was signifi cantly less toxic than sodium azide. Following the injection with 0.2 mu l of these compounds in the hemocoel of young adult wild-type males, the mini mum concentrations of these compounds with complete toxic effects (zero sur vival) were 40 mM sodium azide and 160 mM azidoalanine. Sex-linked recessiv e lethals were scored by the Muller-5 method in three successive broods, re presenting sperms (brood A), spermatids (brood B), and a compiled group of meiotic and premeiotic germ cell stages (brood C). The results provide stro ng experimental evidence that azidoalanine is significantly (p<0.01) mutage nic to all stages of spermatogenesis in Drosophila melanogaster. Sodium azi de, however, was not significantly (p>0.05) mutagenic and did not increase the rate of sex-linked recessive lethals over those produced by the control group injected with 0.45% NaCl. These results indicate the requirement of metabolic activation of azide in Drosophila as a prerequisite for its mutag enic effects. (C) 2000 Elsevier Science B.V. All rights reserved.