High-Throughput Screening and Selection of Pichia pastoris Strains.

Clone screening procedures for Pichia pastoris expression strain comparison rely on the availability of a cultivation environment that ensures equal growth and production capabilities for all assessed transformants. As clonal variation in such experiments is caused by diverging numbers and possibly also genomic locations of integrated (linearized) expression constructs, the productivity assessment of a larger number of strains is mandatory for selecting a set of strains for follow-up bioreactor cultivations in order to define the best-producing clone. Microscale cultivation provides the means to reliably compare growth and productivity of a large number of transformants and by that narrows down the amount of selected strains for scaling up.