Takara-brand pCold Expression Vectors offer cold shock expression technology for high purity and high yield recombinant protein expression. Each vector contains the cold shock protein A (cspA) promoter for expression of high purity and high yield recombinant protein in E. coli. These vectors selectively induce target protein synthesis at low temperatures (15°C) while the bacterial cell is in a state of suppressed host protein expression and decreased protease activity. This results in a higher yield of target protein (at up to 60% of the intracellular protein). In addition to the cspA promoter, all three vectors contain a lac operon (for expression control), ampicillin resistance gene (ampr), ColE1 origin of replication, M13 IG fragment and multiple cloning site (MCS). Two of the vectors also contain a translation enhancing element (TEE). pCold II contains a His tag sequence. These vectors work equally well for non-labeled and radiolabeled recombinant protein expression and can be used in conjunction with the Chaperone Plasmid Set.