One Shot™ PIR2 Chemically Competent E. coli (Invitrogen™)

One Shot PIR2 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 PIR2 strain contains the wild-type pir gene that maintains the donor at ∼15 copies per cell. This strain is recommended for maintaining constructs that express toxic genes or for libraries. PIR2 is made chemically competent and can achieve high transformation efficiency of >1 x 10⁸ 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 PIR2 Chemically Competent E. coli cells offer:
• Wild-type pir gene to maintain vectors that contain the R6Kγ ori at ∼15 copies per cell
• Transformation efficiencies of >1 x 10⁸ cfu/μg
• endA1 mutation that enables increased plasmid DNA yield and quantity
• recA1 mutation that reduces the occurrence of unwanted recombination in cloned DNA
• hsdR for efficient transformation of unmethylated DNA from PCR applications

Convenient and efficient format
PIR2 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
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 the PIR1 strain that carries mutated pir gene and maintain vectors at ∼250 copies per cell.
MultiShot formats are available for high throughput applications.
Explore bacterial growth media formats.