Competent Cells
Competent Cells
Thermo Scientific™ DH5α Competent Cells; High Efficiency
High efficiency, chemically competent E. coli cells ideal for construction of gene banks or generation of cDNA libraries using plasmid-derived vectors
Thermo Scientific™ DH5α Competent Cells
Chemically competent E. coli cells recommended for routine subcloning into plasmid vectors. Subcloning efficiency cells are not suitable for the generation of cDNA libraries.
Thermo Scientific™ DH10B Competent Cells; High Efficiency
High efficiency, chemically competent E. coli cells. The DH10B strain is suitable for cloning DNA containing methylcytosine, 5-hydroxymethylcytosine, and methyladenine, allowing both prokaryotic and eukaryotic genomic DNA to be cloned efficiently.
MilliporeSigma™ Novagen™ DE3 Competent Cell Set
For Protein Expressions
MilliporeSigma™ Novagen™ NovaBlue Singles™ Competent Cells
NovaBlue Singles Competent Cells are designed for ultimate convenience and reliability in plasmid transformation.
Invitrogen™ Subcloning Efficiency™ DH5α Competent Cells
Subcloning Efficiency DH5α Competent Cells are a versatile, chemically competent strain for cloning that provides a transformation efficiency of >1 x 106 cfu/µg plasmid DNA.

Promega Bacterial Strain JM109
Useful host for transformation of pGEM Vectors and production of ssDNA from M18 or phagemid vectors. JM109 is recA- and lacks the E. coli K restriction system. Can be used for blue/white screening.
Thermo Scientific™ BL21(DE3) Competent Cells
Suitable for the expression of non-toxic heterologous genes. The strain contains the lambda DE3 prophage that carries the gene for T7 RNA polymerase under control of a lacUV5 promoter, allowing expression of the T7 RNA polymerase to be induced with IPTG.
MilliporeSigma™ Novagen™ BL21(DE3) Competent Cells
Achieve greater efficiency, reproducibility and convenience with Novagen prepared competent cells. BL21(DE3) is a chemically competent E. coli cell suitable for transformation and high-level protein expression using a T7 RNA polymerase-IPTG induction system.
MilliporeSigma™ Novagen™ BL21 Competent Cells
BL21 host strain is the most widely used host background and has the advantage of being deficient in both lon and ompT proteases.
MilliporeSigma™ Novagen™ Tuner™ (DE3) pLacI Competent Cells
Tuner host strains are lacZY deletion mutants of BL21, which enable adjustable levels of protein expression throughout all cells in a culture. Contains the pLacI plasmid producing extra Lac repressor.
MilliporeSigma™ Novagen™ Origami™ B Competent Cells
Origami B host strains carry the same mutations as the original Origami strain, except that they are derived from a lacZY mutant of BL21 to enable precise control of expression levels using IPTG.
MilliporeSigma™ Novagen™ BL21 (DE3) pLysS Singles™ Competent Cells
BL21 strains are the most widely used hosts for protein expression from pET recombinants and have the advantage of being deficient in both lon and ompT proteases.
MilliporeSigma™ Novagen™ NovaBlue Competent Cells
NovaBlue is a K-12 strain ideally suited as an initial cloning host due to its high transformation efficiency, blue/white screening capability (with appropriate plasmids) and recA endA mutations.
Invitrogen™ One Shot™ MAX Efficiency™ DH5α-T1R Competent Cells
One Shot MAX Efficiency DH5α-T1R Competent Cells are derived from the popular DH5α strain and carry the tonA (fhuA) mutation that confers resistance to T1 and T5 phage.
