Technical advance in fungal biotechnology: development of a miniaturized culture method and an automated high-throughput screening

Aims: The goal of the study was to develop a reliable, reproducible and rapid method of culture in order to screen a large number of fungal transformants. Methods and Results: The method is based upon miniaturized cell cultures and automated expression screening in microwell plates. For the method development, 50 recombinant Aspergillus vadensis clones producing feruloyl esterase B (FaeB) from Aspergillus niger were screened in 6 days. Then a panel of clones showing various behaviours was checked in flasks in order to demonstrate the reproducibility of the method. Using this method, a transformant of A. vadensis producing 1 center dot 2 g l(-1) of FaeB was selected (12-fold more than the A. niger overproducing strain). Conclusions: This miniaturized culture method allows to obtain reliable and reproducible results. The procedure has the advantages of being efficient, time-saving and more efficient than conventional in-flask culture screening as it can screen 800 clones per day after a culture of 3 days. Significance and Impact of the Study: This method could be applied to any other fungal strain culture, enzyme activity or biodiversity screening.