Agrobacterium tumefaciens-mediated transformation of uracil auxotroph Aspergillus fumigatus is an efficient method for target gene knockout / 北京大学学报(医学版)

ABSTRACT

Objective:To investigate the efficiency of Agrobacterium tumefaciensmediated transfor-mation of Aspergillus fumigatus by using pyrG as a recessive selectable marker.Methods: FAP1 and SHO1 genes target sequences,composed of a selectable marker pyrG and the flanking sequences of the FAP1 and the SHO1 genes,were cloned into a binary plasmid pDHt/sk,respectively.The produced plasmids were transformed into A.tumefaciens.The A.tumefaciens and uracil auxotroph A.fumigatus were cocultured in induction medium without uricil and uridine at 24 ℃ for 48 h.To inhibit growth of A.tumefaciens and to select transformants,the cultures were transferred to 37 ℃ and incubated for another 48 h.Results: In this study,A.tumefaciens-medidated transformation of A.fumigatus produced high homologous recombination rates,which was 44%(7 of 16) for FAP1 and 35%(7 of 20) for SHO1.Conclusion: Our study showed that A.tumefaciens-medidated transformation by using pyrG as a recessive selectable marker is an efficient tool for target gene deletion of A.fumigatus.