UV- and EMS- induced mutations affecting synthesis of alkaloids and lipase in Penicillium roquefortii

Abstract

Mutants of a Penicillium roquefortii strain were obtained by ultraviolet irradiation (UV) and ethylmethansulfonate (EMS). Based on alkaloid production, the mutant strains could be divided into four groups: (1) unable to synthesize alkaloids, (2) with a non functional chain of clavin formation, (3) with roquefortine and 3,12-dihydroroquefortine that were not found in the alkaloid fraction and (4) with new compounds, that were not shown in the wild type strain. These data indicate the presence of not less than three different pathways of alkaloids formation in Penicillium roquefortii. On the other hand, all selected mutants produced more lipase than the wild type strain, when using olive oil as a substrate; when cotton seed oil was used many mutant strains produced less lipase activity than the parent strain.