Inducible expression systems are essential molecular tools for production of recombinant proteins. Although there are currently a number of protein expression systems available, there is a need to develop new systems that allow for tighter regulation and higher yield. This invention provides compositions and methods for an inducible protein expression system in E. coli based on a novel propionate inducible promoter.
Expression of recombinant protein in E. coli is highly-regulated by the inducer.
High level of expression can be achieved in the presence of inducer (maximal induction 1500 fold).
The inducer propionate is non-toxic and inexpensive; therefore allowing for large-scale industrial production. In contrast, some commonly used inducers such as IPTG are expensive and toxic to cells.
Uniform expression: cells are uniformly induced to express recombinant protein in the presence of inducer whereas in many other inducible systems, the induction level varies among individual cells in the whole population.
The basal level of expression in the absence of inducer is negligible.
The combined gains in inducibility and yield present many opportunities for the propionate inducible expression system in laboratory and industrial applications.
|United States Of America||Issued Patent||8,178,338||05/15/2012||2005-107|