Electrotransformation of the human pathogenic fungus Scedosporium prolificans mediated by repetitive rDNA sequences

The regions encoding the 5.8S rRNA and the nanking internal transcribed spa cers (ITSI and ITSII) from two isolates of the human pathogenic Fungus Sced osporium prolificans and one isolate of the taxonomically related species P seudallescheria boydii (S. apiospermum) were sequenced. The sequences of th e two S. prolificans isolates were identical. However, there were minor dif ferences between both species. Phylogenetic analysis of known fungal sequen ces confirmed a close relationship between S. prolificans and P. boydii. An attempt was made to transform S. prolificans by electroporation using a pl asmid vector, pMLF2, bearing the Escherichia coil hygromycin B phosphotrans ferase gene (hph) under the control of Aspergillus nidulans promoter and te rminator sequences. To increase transformation efficiency, the sequenced ri bosomal cluster of S. prolificans was used to construct a new vector for ho mologous recombination. (C) 1999 Federation of European Microbiological Soc ieties. Published by Elsevier Science B.V. All rights reserved.