Our Pichia pastoris recombinant protein vector system is a powerful and efficient system for expressing recombinant proteins in this yeast species. P. pastoris is methylotrophic yeast widely used for protein production for research and industrial applications.
In this vector system, the gene of interest is typically cloned under the control of either the glyceraldehyde-3-phosphate dehydrogenase (GAP) promoter or the alcohol oxidase 1 (AOX1) promoter, depending on whether constitutive or inducible expression is desired. The GAP promoter is a strong, constitutive promoter, while the AOX1 promoter is tightly regulated, and strongly inducible by methanol. Both promoters are capable of driving very high-level gene expression, often with the protein of interest accumulating to more than 30% of total cellular soluble protein. In general, the GAP promoter is slightly stronger than the AOX1 promoter in its induced state. We recommend that you perform a time course experiment to optimize expression of your recombinant protein and to determine the best promoter to drive its expression.
Unlike S. cerevisiae, P. pastoris metabolizes methanol as its sole carbon source (a.k.a. methylotrophic), and achieves much higher levels of recombinant protein expression than S. cerevisiae (often 10- to 100-fold higher). In addition, many techniques commonly used with S. cerevisiae can be employed with P. pastoris (e.g. complementation), and common gene annotations and genetic nomenclature simplify research using both species.
For further information about this vector system, please refer to the papers below.