The methylotrophic yeast, Pichia pastoris, has been used as a protein expression system to express over 500 heterologous proteins. P. pastoris provides many advantages over other organisms that have been utilized for this purpose. In this project, we developed a new host/selectable marker and auxotrophic strains of P. pastoris based on methionine biosynthesis to increase P. pastoris's versatility as a host for homologous protein expression. This was accomplished by selecting for a yeast that is deficient in methionine biosynthesis, P. pastoris (yJC239), and gene complementation through transformation with a genomic DNA library.
Bioinformatics show that the P. pastor is MET gene has 54% amino acid identity with 68% similarity to the S. cerevisiae MET2 gene, which codes for homoserine O-transacetylase. We have constructed expression vectors for intracellular and extracellular expression of proteins with the MET2 marker and have also constructed strains with various auxotrophs including me/2.
| Identifer | oai:union.ndltd.org:pacific.edu/oai:scholarlycommons.pacific.edu:uop_etds-1569 |
| Date | 01 January 2002 |
| Creators | Thor, Der |
| Publisher | Scholarly Commons |
| Source Sets | University of the Pacific |
| Detected Language | English |
| Type | text |
| Format | application/pdf |
| Source | University of the Pacific Theses and Dissertations |
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