
pFC20A HaloTag T7 SP6 Flexi Vector
The following vectors are used for inducible expression of HaloTag fusion proteins in E. coli and cell-free systems using the T7 and SP6 RNA polymerase promoters. Expression levels depend highly on the nature of the protein, but in general the N-terminal HaloTag fusion protein can increase expression level, enhance refolding and boost solubility of the expressed protein. HaloTag vectors are supplied as Flexi System vectors. 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. pFN19A/K HaloTag T7 SP6 Flexi Vectors (Cat.# G1891, G1841) are designed for protein expression with an N-terminal HaloTag in T7 and SP6 cell-free expression systems. These vectors are optimized for cell-free expression systems. pFC20A/K HaloTag T7 SP6 Flexi Vectors (Cat.# G1681, G1691) are designed for protein expression with a C-terminal HaloTag in E. coli and SP6 cell-free expression systems. These vectors are optimized for cell-free expression systems. 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.