We are trying to understand the dynamic interactions between molecules within living cells. For biochemical analysis, it can be necessary to use large quantities of recombinant protein. These can be extremely difficult to express in a correctly-folded and functional form.
If a protein was found to be misfolded or insoluble when expressed in bacteria, researchers would either have to resort to mammalian cells, which is expensive and relatively slow, or use synthetic polypeptides. Our protocol allows for high yield expression as well as export of challenging proteins from E.coli. Adding a short cleavable peptide sequence to the amino terminus of the protein not only enhances the production and yield of every protein we have tested to date, but also exports the protein from the cell into the media.
Along with simplifying protein expression, it also simplifies downstream protein purification.