The ESP system provides high-yield protein production in a eukaryotic organism
Quinn Lu * Bruce Jerpseth * Tim Sanchez * John C. Bauer * Alan
Stratagene Cloning Systems, Inc.
Stratagene's EPS yeast protein expression and purification systemllll provides novel opportunities for rapid, inexpensive and high-yield production of proteins in a eukaryotic organism. This system retains many eukaryotic posttranslational modifications of proteins that can be critical for the biological activity of expressed proteins. By using the yeast Schizosaccharomyces pombe as the host and glutathione-S-transferase (GST) as the protein purification tag, the ESP system expresses a protein of interest in yeast as a fusion protein with GST. The fusion protein is then purified using glutathione-agarose beads, and the GST tag can be removed from the protein by proteolytic cleavage with either bovine enterokinase or thrombin.
As numerous genes that are involved in transcriptional regulation and developmental control have been cloned and identified, the demand for homogeneously purified proteins for structural and functional analyses has increased. Although this demand can be partially fulfilled by prokaryotic expression systems, the analysis of eukaryotic proteins, whose functions are determined or influenced by posttranslational modifications, would require expression of the protein in a eukaryotic organism. Stratagene's ESP yeast protein expression and purification system has been created to meet this demand.
The yeast S. pombe is a unicellular eukaryotic organism, with properties that
closely resemble higher eukaryotic organisms regarding chromosome structure and
function, cell cycle control and RNA splicing.1 Stratagene's ESP
system contains a cloning vector with both yeast and Escherichia coli
replication origins, competent cell