TransforMaxTM
Competent Cell
TransforMax™ EPI300™ Chemically Competent E. coli
Applications
- Generation of inducible copy-number clones using the CopyControl™ Cloning System.
Benefits
Genotype
F- mcrA Δ(mrr-hsdRMS-mcrBC) Φ80dlacZΔM15 ΔlacX74 recA1 endA1 araD139 Δ(ara, leu)7697 galU galK λ- rpsL (StrR) nupG trfA dhfr
- Copy-number of clones is under tight control of an inducible promoter linked to thetrfA gene.
- High transformation efficiency with clones of all sizes.
- lacZΔM15for blue/white screening of recombinants.
- Restriction-minus [mcrA, Δ(mrr-hsdRMS-mcrBC)] phenotype enables efficient cloning of methylated DNA.
- Endonuclease-minus (endA1), to ensure high yields of DNA.
- Recombination-minus (recA1), for greater stability of large insert clones.
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Figure 1. Copy number of CopyControl™ BAC clones can be induced 10- to 20-fold in TransforMax™ EPI300™ E. coli. The yield of BAC DNA from CopyControl BAC clones of 110-145 kb increased >14-fold following addition of CopyControl Induction Solution. U=uninduced cells; I=induced cells. |
Genotype
F- mcrA Δ(mrr-hsdRMS-mcrBC) Φ80dlacZΔM15 ΔlacX74 recA1 endA1 araD139 Δ(ara, leu)7697 galU galK λ- rpsL (StrR) nupG trfA dhfr
TransforMax EPI300 Chemically Competent E. coli
- Transformation efficiency of >5 x 108 cfu/µg of pUC19.
*Covered by issued and/or pending patents.
TransforMax™ EC100™ Chemically Competent E. coli
Applications
- Routine cloning of DNA up to 200 kb.
Benefits
Genotype
F- mcrA Δ(mrr-hsdRMS-mcrBC) Φ80dlacZΔM15 ΔlacX74 recA1 endA1 araD139 Δ(ara, leu)7697 galU galK λ- rpsL (StrR) nupG
- High transformation efficiency with clones of all sizes, including BAC clones (Table 1).
- lacZΔM15for blue/white screening of recombinants.
- Restriction minus [mcrA, Δ(mrr-hsdRMS-mcrBC)] enables efficient cloning of methylated DNA.
- Endonuclease minus (endA1) to ensure high yields of DNA.
- Recombination minus (recA1) for greater stability of large cloned inserts.
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Table 1. Comparison of the transformation efficiencies of TransforMax™ EC100™ E. coli with a variety of DNAs.Transformations were performed using 50 µl of competent cells and either supercoiled DNAs of the indicated sizes or a 1-µl aliquot from a standard 10-µl ligation reaction. Results shown are in cfu/µg of DNA and are the average transformation efficiencies obtained from several trials. |
Genotype
F- mcrA Δ(mrr-hsdRMS-mcrBC) Φ80dlacZΔM15 ΔlacX74 recA1 endA1 araD139 Δ(ara, leu)7697 galU galK λ- rpsL (StrR) nupG
TransforMax EC100 Chemically Competent E. coli
- Transformation efficiency of >5 x 108 cfu/µg of pUC19.
TransforMax™ EPI300™-T1R Electrocompetent E. coli
Applications
- Construction of inducible-copy-number genomic libraries using the CopyControl™ Cloning System, with clones that are resistant to contaminating phage T1 and T5.
Like the standard TransforMax EPI300 E. coli, this strain has been specially engineered for use with Epicentre's CopyControl™ Cloning Systems.* The cells contain an inducible mutant trfA gene whose gene product is required for initiation of replication from the oriV contained on the CopyControl pCC1™ Vectors or on clones that have been retrofitted with CopyControl capability using the EZ-Tn5™<oriV/KAN-2> Insertion Kit. This process allows TransforMax EPI300-T1R E. coli to maintain CopyControl vectors at single copy until induction occurs immediately before DNA purification.
Benefits
Genotype
F- mcrA Δ(mrr-hsdRMS-mcrBC) Φ80dlacZΔM15 ΔlacX74 recA1 endA1 araD139 Δ(ara, leu)7697 galU galK λ- rpsL (StrR) nupG trfA tonA
- tonAfor resistance to bacteriophages T1 and T5.
- trfAgene under tight control of an inducible promoter for copy-number control of CopyControl clones and clones retrofitted with the EZ-Tn5<oriV/KAN-2> Transposon.
- High transformation efficiency of both large and small clones.
- lacZΔM15for blue/white screening of recombinants.
- Readily accepts large DNAs for construction of large-insert genomic libraries.
- Restriction minus [mcrA, Δ(mrr-hsdRMS-mcrBC)] enables efficient cloning of methylated DNA.
- Endonuclease minus (endA1) to ensure high yields of DNA.
- Recombination minus (recA1) for greater stability of large cloned inserts.
F- mcrA Δ(mrr-hsdRMS-mcrBC) Φ80dlacZΔM15 ΔlacX74 recA1 endA1 araD139 Δ(ara, leu)7697 galU galK λ- rpsL (StrR) nupG trfA tonA
*Covered by issued and/or pending patents.
TransforMax™ EC100™-T1R Electrocompetent E. coli
Applications
Phage T1-resistant TransforMax EC100-T1R E. coli are ideal for most cloning applications. However, the phage T1-resistant TransforMax EC100-T1R E. coli should not be used with Epicentre's CopyControl™ Cloning Systems.
- Routine cloning of DNA from plasmid, fosmid, and BAC vectors, with resistance to phage T1 and T5.
Phage T1-resistant TransforMax EC100-T1R E. coli are ideal for most cloning applications. However, the phage T1-resistant TransforMax EC100-T1R E. coli should not be used with Epicentre's CopyControl™ Cloning Systems.
Benefits
Genotype
F- mcrA Δ(mrr-hsdRMS-mcrBC) Φ80dlacZΔM15 ΔlacX74 recA1 endA1 araD139 Δ(ara, leu)7697 galU galK λ- rpsL (StrR) nupG tonA
- tonAfor resistance to phage T1 and phage T5.
- High transformation efficiency with clones of all sizes–including BAC clones.
- lacZΔM15for blue/white screening of recombinants.
- Readily accepts large DNAs for construction of large-insert genomic libraries.
- Restriction minus [mcrA, Δ(mrr-hsdRMS-mcrBC)] enables efficient cloning of methylated DNA.
- Endonuclease minus (endA1) to ensure high yields of DNA.
- Recombination minus (recA1) for greater stability of large cloned inserts.
F- mcrA Δ(mrr-hsdRMS-mcrBC) Φ80dlacZΔM15 ΔlacX74 recA1 endA1 araD139 Δ(ara, leu)7697 galU galK λ- rpsL (StrR) nupG tonA
TransforMax™ EC100D™ pir+ and pir-116 Electrocompetent E. coli
Applications
- Rescue cloning of transposition mutants created using the EZ-Tn5™
ori/KAN-2> Insertion kit or Transposome™, or the HyperMu™ ori/KAN-1>Tnp Transposome.
- Propagation of plasmids tagged with the EZ-Tn5
ori/KAN-2> Insertion kit.
The TransforMax EC100D pir+ cells will maintain R6Kγori containing plasmids at approximately 15 copies per cell,1 for cloning of potentially toxic or unstable DNA sequences. The TransforMax EC100D pir-116 cells are for high-copy propagation of up to 250 rescue plasmid copies per cell.1
Benefits
Genotypes
- Accepts large clones for unbiased propagation and stability of large rescue clones.
- lacZΔM15for blue/white screening of recombinants.
- Restriction minus [mcrA, Δ(mrr-hsdRMS-mcrBC)] enables efficient cloning of methylated DNA.
- Endonuclease minus (endA1) to ensure high yields of DNA.
- Recombination minus (recA1) for greater stability of large cloned inserts.
TransforMax EC100D pir+ Electrocompetent E. coli:
FF- mcrA Δ(mrr-hsdRMS-mcrBC) φ80dlacZΔM15 ΔlacX74 recA1 endA1 araD139 Δ(ara, leu)7697 galU galK λ- rpsL (StrR) nupG pir+(DHFR)
FF- mcrA Δ(mrr-hsdRMS-mcrBC) φ80dlacZΔM15 ΔlacX74 recA1 endA1 araD139 Δ(ara, leu)7697 galU galK λ- rpsL (StrR) nupG pir+(DHFR)
TransforMax EC100D pir-116 Electrocompetent E. coli:
F- mcrA Δ(mrr-hsdRMS-mcrBC) φ80dlacZΔM15 ΔlacX74 recA1 endA1 araD139 Δ(ara, leu)7697 galU galK λ- rpsL (StrR) nupG pir-116(DHFR)
F- mcrA Δ(mrr-hsdRMS-mcrBC) φ80dlacZΔM15 ΔlacX74 recA1 endA1 araD139 Δ(ara, leu)7697 galU galK λ- rpsL (StrR) nupG pir-116(DHFR)
Transformation Efficiency
Greater than 1 x 109 colony forming units (cfu)/µg with pR6Kan control DNA.
Greater than 1 x 109 colony forming units (cfu)/µg with pR6Kan control DNA.
References
- Metcalf, W.W. et al. (1994) Gene 138, 1