Search Thermo Fisher Scientific
Thermo Scientific Competent Cells
Confidently competent
Thermo Scientific DH10B, DH5α, and BL21(DE3) competent cells are produced with stringent quality control to enable reliable, consistent performance in cloning workflows. Thermo Scientific DH10B competent cells are also included in the Thermo Scientific CloneJET PCR Cloning Kit and in the Thermo Scientific Phusion Site-Directed Mutagenesis Kit.
Which Thermo Scientific competent cells should I choose?
 Thermo Scientific DH10B Competent Cells |  Thermo Scientific DH5α Competent Cells |  Thermo Scientific DH5α Competent Cells for Subcloning |  Thermo Scientific BL21(DE3) Competent Cells | |
| Quantity | 20 reactions 10 x 100 µL | 20 reactions 10 x 100 µL | 40 reactions 4 x 500 µL | 20 reactions 10 x 100 µL |
| Primary applications |
|
|
|
|
| Transformation efficiency (cfu/µg pUC19 DNA) | > 1x109 | > 1x109 | > 1x106 | > 1x107 |
| Notes | Not suitable for preparing unmethylated DNA | Not suitable for preparing unmethylated DNA | Not suitable for preparing unmethylated DNA | Not suitable for maintenance of expression plasmids |
| Genotype | F– mcrA Δ(mrr-hsdRMS-mcrBC) φ80lacZΔM15 ΔlacX74 recA1 endA1 araD139 Δ (ara-leu)7697 galU galK λ– rpsL(StrR) nupG | F– φ80lacZDM15 D(lacZYA-argF) U169 recA1 endA1 hsdR17 (rk–, mk+) phoA supE44 l– thi–1 gyrA96 relA1 | F– φ80lacZDM15 D(lacZYA-argF) U169 recA1 endA1 hsdR17 (rk–, mk+) phoA supE44 l– thi–1 gyrA96 relA1 | F– ompT hsdSB (rB-mB-) gal dcm (DE3) |
For competent bacteria with even higher transformation efficiencies and more convenient formats, explore Invitrogen competent cells
Thermo Scientific competent cell cloning and mutagenesis kits
Thermo Scientific CloneJET PCR Cloning Kit with DH10B
20 or 40 reactions
Order
Achieve high transformation efficiencies with Thermo Scientific competent cells
Thermo Scientific DH10B competent cells
The transformation efficiencies of DH10B competent cells (Thermo Fisher Scientific), 10-beta competent E. coli I (NEB), and
Thermo Scientific DH5α competent cells
The transformation efficiencies of DH5α competent cells and 5-alpha competent
Thermo Scientific DH10B competent cell transformation efficiency in the CloneJET PCR cloning workflow
A 976 bp PCR product was generated using either Thermo Scientific DreamTaq Green PCR Master Mix (2X) (represented by grey bar) or Thermo Scientific Phusion Hot Start II DNA Polymerase (represented by blue bar) and ligated into a cloning vector according to the manufacturers’ protocols. The transformation efficiency obtained with the control fragment provided with the CloneJET PCR Cloning Kit is represented by the yellow bar. Ligation mixtures were used to transform Thermo Scientific DH10B cells. The expected transformation efficiency of competent cells is >1 x 107 CFU/µg DNA. The transformation efficiency specification of DH10B competent cells with pUC19 DNA is 1 x 109 CFU/µg DNA. The values shown are the average of five transformations. Error bars represent standard deviations.
Efficient recovery of mutants using Thermo Scientific DH10B competent cells
The Thermo Scientific Phusion Site-Directed Mutagenesis Kit has been tested using the control plasmid and control primer mix provided in the kit, in conjunction with Thermo Scientific DH10B competent cells. The primer mix reverts the mutated internal stop codon to a functional codon; a successful mutagenesis reaction results in blue colonies on ampicillin agar plates containing X-Gal and IPTG. A high rate of mutagenesis and high transformation efficiency means that numerous mutants can be directly subjected to sequencing, eliminating additional analysis steps.
Resources
Manuals
Molecular cloning articles
Flyer
Support
Have any questions on competent cells or transformation? Click below to access overviews, videos, genotype guides and educational resources.
Cloning Support Center
Find tips, troubleshooting help, and resources for you cloning applications
Molecular Biology Product Discontinuations
Find an alternate to a discontinued molecular biology product using our discontinuation database.
Product support documentation
Search for manuals, protocols, Material Safety Data Sheets, product literature and certificates by catalog number or product name.
Contact Us
Email or call our technical application scientists for additional questions regarding competent cells.