Abstract
SUMMARY: A method for the selection of auxotrophic mutants in Aspergillus nidulans using N-glycosyl-polifungin has been developed. The method results in about 9000-fold enrichment. All types of auxotrophs were obtained. Under certain conditions preferential selection of nucleic acid hydrolysate-requiring auxotrophs was observed. The frequency of occurrence of these mutants was about 50% of all colonies tested. Cysteine auxotrophs of A. nidulans were obtained for the first time by means of this method.