Establishing an Efficient Genetic Manipulation System for Sulfated Echinocandin Producing Fungus .

Micafungin is an important echinocandin antifungal agent for the treatment of invasive fungal infections. In industry, micafungin is derived from the natural product FR901379, which is a non-ribosomal cyclic hexapeptide produced by the filamentous fungus . The difficulty of genetic manipulation in restricts the clarification of FR901379 biosynthetic mechanism. In this work, we developed an efficient genetic manipulation system in the industrial FR901379-producing strain MEFC009. Firstly, a convenient protoplast-mediated transformation (PMT) method was developed. Secondly, with this transformation method, the essential genetic elements were verified. Selectable markers , , and can be used for the transformation, and promotors , , and are functional in MEFC009. Thirdly, the frequency of homologous recombination was improved from 4 to 100% by deleting the gene, resulting in an excellent chassis cell for gene-targeting. Additionally, the advantage of this genetic manipulation system was demonstrated in the identification of the polyketide synthase (PKS) responsible for the biosynthesis of dihydroxynapthalene (DHN)-melanin. This genetic manipulation system will be a useful platform for the research of FR901379 and further genome mining of secondary metabolites in .