Agrobacterium tumefaciens-mediated transformation of a taxol-producing endophytic fungus, Cladosporium cladosporioides MD2.

In this study, an Agrobacteriurn tumefaciens-mediated transformation (ATMT) protocol was successfully developed for the genetic transformation of a taxol-producing fungus, Cladosporium cladosporioides MD2, and the co-cultivation conditions affecting the transformation efficiency were optimized. The optimal transformation conditions were that 1 ml of C. cladosporioides MD2 spore suspension (108 spores/ml) was mixed with an equal volume of A. tumefaciens cultures, which contained 400 μl of A. tumefaciens LBA4404 (OD660 ≈ 0.6) and 600 μl LB medium that were used to make up difference in volume, and the mix cultures were supplemented with 300 μM acetosyringone (AS) and co-cultivated at 26°C and 50 rpm for 48 h. Stable transformants were obtained through analysis of the mitotic stability of inserted T-DNA and the presence of hygromycin resistance gene (hpt II). This study laid a fine groundwork for development of transgenic C. cladosporioides MD2 strains.