Because that state will allow obtaining a functional fusion construct or to cleave of the NUMAswitch with a site specific protease. Currently, this is a serious hurdle since either renaturation does not work at all or it is very inefficient (≤ 25% yield). The NUMAswitch offers the solution to that issue and fusion peptides can efficiently be renatured (functionality 2: RENATURATION). After the inclusion bodies of requested peptides fused to the NUMAswitch are solubilized (in chaotropic salts, detergents, organic solvents, bases etc.), they are incubated with NUMAFERM’s proprietary renaturation buffer. The construct is then renatured highly efficient (close to 100% yield) with concentrations in the mg/mL range (ON-state of the switch, see Figure 3, step 3). This enables the utilization of functional, soluble fusion peptides or the application of site-specific proteases (which are non-functional in the environment of solubilization reagents described above) to cleave-off the peptide.
Altogether, the NUMAswitch offers the advantages of IBtags (protection of peptides from proteolysis, high-level expression, good initial purity), solves existent limitations (inefficient renaturation) and serves as reliable, cost-efficient, recombinant production platform for pure peptides aswell as functional fusion peptides.