Tools for advanced and targeted genetic manipulation of the β-lactam antibiotic producer Acremonium chrysogenum

Cephalosporins

“…The use of this approach recently resulted in the generation of an A. chrysogenum ∆Acku70 strain. Subsequent gene deletion experiments using this strain as a recipient have shown recombination rates of between 50 and 89 %, 1 in contrast to the 0.6 % rate observed for the deletion of the Acku70 gene itself [ 75 ].…”

“…After induction, the recombinase gene is expressed and the recombinase subsequently excises the complete fl ipper cassette, thus leaving only one 34-bp FRT site in the genome. This approach was recently used to generate a marker-free strain lacking the Acku70 gene, representing a good recipient strain for further gene deletion experiments [ 75 ].…”

“…For this, the heterologous xylose-inducible promoter Smxyl from Sordaria macrospora was used [ 75 ]. This promoter is a valuable tool for the recombination system as well as for other applications in which controlled gene expression is desirable.…”

Inducible promoters and functional genomic approaches for the genetic engineering of filamentous fungi

“…Interestingly, the latter was proven to be functional in other filamentous fungi from the order Sordariomycetes (Bloemendal et al 2014; Kopke et al 2010). This includes the well-established β-lactam producer Acremonium chrysogenum for which three controllable promoter systems were developed in recent years.…”

“…Both promoters are very effective in A. chrysogenum and contribute to the rather limited number of molecular tools for this highly important industrial fungus. Furthermore, the Smxyl promoter was successfully used for the application of a one-step FLP/ FRT recombination system in order to construct marker-free transgenic strains (Blatzer et al 2014; Bloemendal et al 2014). …”