One Shot PIR1 Chemically Competent E. coli cells are for use with vectors that contain the R6Kγ origin of replication (e.g., pUni/V5-His-TOPO for recombination with an Echo cloning system). The pir gene encodes the replication protein π, which is required to replicate and maintain plasmids containing the R6Kγ origin. The PIR1 strain contains a mutant allele of the pir gene that maintains the donor vector construct at ∼250 copies per cell. PIR1 cells are competent and can achieve high transformation efficiency of >1 x 10⁹ cfu/μg supercoiled plasmid.

R6Kγ allows tight control and selection and has been used in various applications including genome engineering, mutagenesis studies, bacterial artificial chromosome (BAC) construction, high-capacity extrachromosomal vector systems, and suicide plasmid construction.

One Shot PIR1 Chemically Competent E. coli cells offer:
• pir gene to maintain vectors that contain the R6Kγ ori at ∼250 copies per cell
• Transformation efficiencies of >1 x 10⁹ cfu/μg
• endA1 mutation enables increased plasmid DNA yield and quantity
• recA1 mutation reduce occurrence of unwanted recombination in cloned DNA
• hsdR for efficient transformation of unmethylated DNA from PCR applications

Convenient and efficient format 
PIR1 Chemically Competent E. coli cells are supplied in the convenient, single-reaction One Shot format. Each tube contains enough cells for one transformation, reducing freeze-thaw cycles and money wasted on unused cells.

Genotype
F^–∆lac169 rpoS(Am) robA1 creC510 hsdR514 endA recA1 uidA(∆MluI)::pir-116
Genetic marker descriptions

Find the strain and format that fit your needs
Multiple DH strains are available in chemically competent and electrocompetent cell formats.
We offer PIR2 strain that carries wild-type pir gene and maintain vectors at ∼15 copies per cell.
MultiShot formats are available for high throughput applications.
Explore bacterial growth media formats.