One Shot TOP10 Chemically Competent E. coli are ideal for high-efficiency cloning and plasmid DNA propagation and are provided at a transformation efficiency of 1 x 10⁹ cfu/μg plasmid DNA. These cells allow stable replication of high-copy number plasmids and are the same competent cells that come with many of our cloning kits. TOP10 E. coli cells are genetically similar to the DH10B strain and have been reported to be more resilient to stress conditions like osmotic shock and acidic pH stress.

One Shot TOP10 cells:
• Maximize cloning efficiency in a single-tube format
• Provide enhanced genomic DNA cloning capabilities

TOP10 Chemically Competent E. coli cells carry mutations in the methylation-dependent restriction system (mcrA, mcrBC, and mrr) allowing the cloning of both prokaryotic and eukaryotic genomic DNA, as well as efficient plasmid rescue from eukaryotic genomes. Similar to other DH strains, TOP10 has the lacZΔM15 genotype, providing for the option of blue-white screening on plates containing either X-Gal or Bluo-Gal. The inclusion of recA1 and endA1 mutations increase insert stability and improve the quality of plasmid DNA prepared from minipreps.

One Shot TOP10 Chemically Competent E. coli cells offer:
• Transformation efficiencies of >1 x 10⁹ cfu/μg
• hsdR for efficient transformation of unmethylated DNA from PCR amplifications
• mcrA for efficient transformation of methylated DNA from genomic preparations
• lacZΔM15 for blue/white color screening of recombinant clones
• endA1 for cleaner DNA preparations and better results in downstream applications due to elimination of nonspecific digestion by Endonuclease I
• recA1 for reduced occurrence of nonspecific recombination in cloned DNA
• Expression from the lac promoter without IPTG

Easy-to-use One Shot format
TOP10 Chemically Competent E. coli cells are supplied in the convenient, single-reaction One Shot format. The single-tube, single-use format accomodates allows all steps of the transformation protocol, up to plating, to take place in the same tube, helping save time and prevent contamination.

Genotype
F^–mcrA Δ(mrr-hsdRMS-mcrBC) φ80lacZΔM15 ΔlacX74 recA1 araD139 Δ(ara-leu)7697 galU galK λ–rpsL(Str^R) endA1 nupG

Find the strain and format that fit your needs 
We offer other DH strains in chemically competent and electrocompetent cell formats.
The TOP10 strain is available in several MultiShot formats for high throughput applications.
Explore bacterial growth media formats.