ADVANCES IN THE USE OF PICHIA-PASTORIS FOR HIGH-LEVEL GENE-EXPRESSION

The Pichia pastoris system has the potential for very high level production of foreign proteins. This, together with the recent availability of this system in kit form, has changed Pichia from being an expression system with only specialized biotechnological applications to one that is widely used for rapid expression in the laboratory. The development of G418 selection protocols has simplified the rapid isolation of multicopy transformants efficiently expressing intracellular proteins. In addition, several strategies are now also available for optimizing secretion, such as the generation of clones with progressively increasing vector copy number, expression screening in microtitre plates, and minimizing proteolysis by a number of techniques.