The pGEM®-T Vector Systems are convenient systems to clone PCR products generated by certain thermostable polymerases. These polymerases often add a single deoxyadenosine, in a template-independent fashion, to the 3´-ends of the amplified fragments. The pGEM®-T Vector is ready to use in ligation reactions, prepared by cutting the pGEM®-5Zf(+) Vector with EcoRV and adding a 3´ terminal thymidine to both ends. These single 3´-T overhangs at the insertion site greatly improve the efficiency of ligation of a PCR product into the plasmid by preventing recircularization of the vector and providing a compatible overhang for ligation of PCR products with A overhangs.
T7 and SP6 RNA polymerase promoters flank a multiple cloning region within the α-peptide coding region for β-galactosidase. Insertional inactivation of the α-peptide allows recombinant clones to be directly identified by Blue/White Screening on indicator plates. The vector allows preparation of single-stranded DNA due to its f1 Origin of Replication.
The multiple cloning site is flanked by recognition sites for the restriction enzyme BstZI, allowing release of the insert by a single-enzyme digestion. Alternatively, a double digestion may be used to release the insert from the vector.
The pGEM®-T Vector System II contains JM109 Competent Cells in addition to all of the pGEM®-T Vector System I components.
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