Phagemid pComb3 XTT vector
pComb3X is the newest of the pComb vectors. Improvements over pComb3 include increased stability and introduction of SfiI cassette for cloning of full Fab, scFv, peptide and other protein for phage display. 6xHis and HA tags allow for purification and detection. An amber stop codon was introduced to turn-off expression of the pIII fusion protein by switching to a non-supressor strain of E. coli allowing production of soluble protein without subcloning. Alternatively, the gene for phage protein pIII can be removed by SpeI/NheI digest. pComb3XSS is the vector we normally ship. The “TT” refers to the human Fab to tetanus toxin from which the kappa light chain constant region and Fd can be amplified.