Escherichia coli is one of the most widely used hosts for recombinant protein production. In most cases, especially when high levels of target proteins are required, plasmid-borne expression is the method of choice for this purpose. The availability of a plethora of E. coli plasmid expression vectors with various promoters, selection markers, purification tags, fusion partners and auxiliary proteins has greatly simplified the process of cloning and expression in this microorganism...