We aimed her mainly to evaluate the contribution of newly employed bromate selection system, in obtaining new Aspergillus niger nitrate/nitrite assimilation defective mutants, through Ultraviolet treatment (UV), 1, 2, 7, 8-Diepoxyoctane (DEO), phenols mixture (Phx)) and spontaneous treatments. The newly employed bromate selection system was able to specify only two putative novel mutant types designated brn (bromate resistant but chlorate sensitive (RS) strain, which may specify nitrite specific transporter) and cbrn mutants (bromate resistant and chlorate resistant strain, which may specify nitrate/nitrite bispecific system). The most relevant and innovative findings of this research work involve the isolation of the RR (cbrn) mutants (a new type of... |