启动子：Lac/lac promoter

复制子：pUC ori

质粒大小：4991 bp

质粒标签：C-6×HIS，C-HA

原核抗性：Amp+

克隆菌株：TG1

培养条件：37℃

pComb3X is the newest of the pComb vectors. Improvements over pComb3 include increased stability and introduction of an asymmetric SfiI cassette for directional 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 recommended for preparation of vector for library cloning. The “SS” refers to the double stuffer, a 1200bp stuffer in the Fab light chain cloning region bounded by SacI and XbaI restriction sites and a 300bp stuffer in Fab heavy chain cloning region bound by XhoI and SpeI restriction sites. Also, the 1600bp double stuffer (both stuffers plus the leader sequence between the Fab light chain and heavy chain cloning regions) can be removed by SfiI digest so that non-Fab genes of interest can be cloned. Also available on Addgene: pComb3XTT and pComb3XLambda are only needed at templates for the construction of chimeric Fab libraries as described in Phage Display: A Laboratory Manual. pComb3XTT can also be used as an Fab expression control. 3rd generation plasmid for phage display on modified geneIII, contains stuffer fragment.