Mustard-gas Mutation in Aspergillus nidulans

Abstract

THE production of ‘biochemical ‘mutants of fungi by means of ultra-violet or X-radiation has been reported by Beadle and Tatum^1,2 (Neurospora spp.), Fries^3,4,5,6 (Ophiostoma spp.) and Pontecorvo⁷ (Aspergillus and Penicillium spp.). Following the use of mustard-gas (β,β'-dichlorodiethyl sulphide) in producing mutations in the vinegar fly (Drosophila melanogaster) by Auerbach and Robson⁸, this reagent has been used by Horowitz et al.⁹ to produce mutations in Neurospora spp. A method for isolating strains of Aspergillus nidulans deficient for a specific amino-acid, cystine, from a mixture of mutants produced by mustard-gas, is now described. These special mutants grow normally in presence of cystine but are unable to grow with sulphate as sole sulphur source.