Highly efficient gene targeting in the Aspergillus niger kusA mutant.

Gene targeting frequencies in Aspergillus niger are often very low and hamper efficient functional genomics in this biotechnologically important fungus. Deletion of the A. niger kusA gene encoding the ortholog of the Ku70 protein in other eukaryotes, dramatically improved homologous integration efficiency and reached more than 80% compared to 7% in the wild-type background, when 500bp homologous flanks were used.

A Bacillus megaterium plasmid system for the production, export, and one-step purification of affinity-tagged heterologous levansucrase from growth medium.

A multiple vector system for the production and export of recombinant affinity-tagged proteins in Bacillus megaterium was developed. Up to 1 mg/liter of a His6-tagged or Strep-tagged Lactobacillus reuteri levansucrase was directed into the growth medium, using the B. megaterium esterase LipA signal peptide, and recovered by one-step affinity chromatography.