These untagged vectors are used for inducible expression of proteins in E. coli and cell-free systems using the T7 RNA polymerase promoter. Supplied as vectors used with the Flexi Cloning System.

• Untagged Bacterial Expression Vectors
• Generate protein from T7 promoter in E. coli and cell-free expression systems
• Options for Kanamycin and Ampicillin resistance
• Starting vector for transferring ORFs into other Flexi(R) Vectors

The following vectors are used for inducible expression of proteins in E. coli and cell-free systems using the T7 RNA polymerase promoter. The Flexi Vector System is a simple, directional cloning method for protein-coding sequences. It is based on two rare-cutting restriction enzymes, SgfI and PmeI, and provides a rapid, efficient and high-fidelity way to transfer protein-coding regions between a variety of Flexi Vectors without the need to resequence. Direct transfers can only occur between two N-terminal tagged vectors or from an N-terminal to a C-terminal vector. pF1A/K T7 Flexi Vectors (Cat.# C8441, C8451) are designed for untagged protein expression. Note: Flexi Vectors contain the lethal barnase gene to reduce background colonies without inserts during the subcloning procedure. Using the Flexi Vector Cloning System replaces the barnase gene with your insert. These vectors, as purchased, cannot be cultured in normal laboratory strains of E. coli without an insert.

C-terminal vectors allow expression of C-terminal-tagged proteins. The vectors can act as acceptors of protein-coding regions flanked by SgfI and PmeI, but they lack a PmeI site and have an EcoICRI blunt-ended site that can’t be removed from the C-terminal Flexi vectors and transferred to other Flexi vectors.

Researchers can choose between various initial applications and transfer to others as needed. Systems can adapt to high throughput formats for larger screening projects. They’re based on two rare-cutting restriction enzymes, SgfI and PmeI, to provide an efficient and high-fidelity way to transfer protein-coding regions between a variety of Flexi vectors without needing to resequence. All Flexi vectors carry the lethal barnase gene, which is replaced by the DNA fragment of interest and acts as a positive selection for successful ligation of the insert.