SUMO Technology and Difficult to Express Proteins

Production of recombinant proteins routinely encounters problems, including formation of inclusion bodies, incorrect protein conformation, toxicity to the host cell, and low protein yield. These issues are most often addressed by using an alternative host or genetically fusing the protein of interest (POI) to a carrier protein (fusion tag).  Attachment of the C-terminus of SUMO (Small Ubiquitin Like Modifier) to the N-terminus of a protein of interest can dramatically improve protein solubility, achieve native protein folding, and increase total yield by improving expression and decreasing degradation. LifeSensors has pioneered SUMO fusion technology, which increases the quantity and quality of numerous recombinant proteins in both prokaryotic and eukaryotic expression hosts.

Our SUMO-tag expression systems maximize the yield of soluble, functional proteins in E. coli. SUMO functions as both a chaperonin and initiator of protein folding, improving the solubility and yield of your POI. De-sumoylases remove the SUMO tags, releasing your protein with the desired N-terminal amino acid. Both SUMO tags and de-sumoylases contain 6xHis tags allowing efficient subsequent removal, leaving pure protein.

The SUMO Pro system is designed for expression and purification of proteins from E. coli. Since all eukaryotic cells contain SUMO and SUMO proteases, the latter of which will cleave SUMO-fusion proteins immediately following expression, LifeSensors has engineered SUMOstar, a SUMO tag for use in eukaryotic hosts, which is resistant to endogenous proteases, thus preserving enhanced expression, increased solubility and native folding.  SUMOstar fusion proteins can be cleaved only with SUMOstar protease.