Attempt at gene reversion of a desired phenotype as a rescue against strain degeneration

Mutagenesis may lead to the production of antibiotic producer revertant derivatives from a non-producer degenerate originally active against skin pathogens. All of the producer revertants examined in the present study were phenotypically different from the producer parental mutant. Most of the revertants were active against plant pathogens, the test fungus used for screening being a plant pathogen. The selective pressure of the test fungus for isolation of revertants may prove very useful in producing a revertant derivative of a desired phenotype.