QIAexpress pQE vectors and constructs can be maintained in any E. coli strain that is ampicillin-sensitive and carries the pREP4 repressor plasmid, or harbors the lacIq gene on the F-factor episome. Alternatively, the pQE-80L series of expression vectors which encodes a lacIq repression module, allows use of any E. coli host strain. Promoter primer: 5'-CCCGA AAAGT GCCAC CTG-3'; Type III/IV primer: 5'-CGGAT AACAA TTTCA CACAG-3'; Reverse primer: 3'-GGTCA TTACT GGAGT CTTG-5'