Development of a modified positive selection medium that allows to isolate Aspergillus oryzae strains cured of the integrated niaD-based plasmid.


Journal Article

The nitrate reductase gene (niaD) is the most frequently utilized as a selectable marker for homologous integration at the niaD locus of Aspergillus oryzae. In this study we developed a method for curing of the niaD-based plasmid integrated on the A. oryzae genome. Positive selection using a modified chlorate medium containing leucine as a nitrogen source enabled efficient isolation of the strains deficient in nitrate assimilation from the niaD(+) transformant. PCR analysis of the strains confirmed that the homologously integrated plasmid carrying the h2b-egfp fusion gene was cured by intrachromosomal recombination which was accompanied by the loss of the EGFP-fluorescence.

Full Text

Duke Authors

Cited Authors

  • Ishi, K; Watanabe, T; Juvvadi, PR; Maruyama, J-I; Kitamoto, K

Published Date

  • December 2005

Published In

Volume / Issue

  • 69 / 12

Start / End Page

  • 2463 - 2465

PubMed ID

  • 16377911

Pubmed Central ID

  • 16377911

International Standard Serial Number (ISSN)

  • 0916-8451

Digital Object Identifier (DOI)

  • 10.1271/bbb.69.2463


  • eng

Conference Location

  • England