Learn how to use this product The pASG-IBA103 vector is a cytoplasmic vector designed for the expression of recombinant proteins with a C-terminal Twin-Strep-tag® in E. coli. The vector carries an ampicillin resistance cassette for the selection of transformed E. coli cells, an F1 and ColE1 origin for a high plasmid copy number, and the inducible tetracycline promoter/operator for the regulated expression of proteins. The tet-promoter works independently of the genetic background of E. coli, meaning that the vector can be combined with any E. coli strain. Expression of the recombinant protein is induced by the addition of anhydrotetracycline, which does not exhibit antibiotic activity and is a derivative of tetracycline. Furthermore, it should be noted that cloning into pASG-IBA Acceptor Vectors compulsorily requires the restriction enzyme Esp3I, as no other MCS for the integration of a gene of interest is available. In addition to the direct cloning of the gene of interest into pASG-IBA vectors with Esp3I, another option via a so-called Entry Vector is possible.