ElectroMAX™ DH10B T1 Phage-Resistant Competent Cells

Citations & References (4)

Invitrogen™

ElectroMAX™ DH10B T1 Phage-Resistant Competent Cells

ElectroMAX DH10B T1 Phage-Resistant Competent Cells offer transformation efficiencies that are among the highest we offer and can exceed 1Read more

Catalog Number	Quantity
12033015	5 x 100 μL

Catalog number 12033015

Price (CLP)

443.290

Add to cart

Quantity:

5 x 100 μL

Price (CLP)

443.290

Add to cart

ElectroMAX DH10B T1 Phage-Resistant Competent Cells offer transformation efficiencies that are among the highest we offer and can exceed 1 x 10¹⁰ cfu/μg plasmid DNA in efficiency. They are ideal for applications requiring high-efficiency transformation, including cDNA and gDNA library construction.

ElectroMAX DH10B cells:
• Maximize yield of transformants from limited cloning products
• Permit efficient cloning of methylated DNA
• Are resistant to T1 and T5 bacteriophages
• Support blue/white screening by α-complementation on plates containing X-Gal or Bluo-Gal
• Deliver high-yield plasmid preparations for downstream applications

Phage-resistant representative libraries from a single transformation
The tonA mutation in DH10B cells confers resistance to bacteriophages T1 and T5, safeguarding valuable libraries against contamination. Additionally, mutations in the methylation-dependent restriction system (mcrA, mcrBC, and mrr) make ElectroMAX DH10B T1 Phage-Resistant Cells ideal for construction of genomic libraries of both prokaryotic and eukaryotic genomic DNA and allow for efficient plasmid rescue from eukaryotic genomes. ElectroMAX DH10B T1 Phage-Resistant Cells are suitable for construction of gene banks, for the generation of cDNA libraries using plasmid-derived vectors, and for situations when DNA is limiting. This strain also has the Φ80lacZΔM15 genotype, providing for the option of blue/white screening on plates containing either X-Gal or Bluo-Gal. Finally, the endA1 mutation makes DH10B an excellent vehicle for amplifying plasmid DNA for subsequent extraction and purification.

Genotype
F^-mcrA Δ(mrr-hsdRMS-mcrBC) Φ80lacZΔM15 ΔlacX74 recA1 endA1 araD139Δ(ara, leu)7697 galU galK λ^-rpsL nupG tonA

Find the strain and format that fits your needs
DH10B cells are available in both electrocompetent and chemically competent formats.
ElectroMAX DH10B cells are suitable for cDNA or gDNA library construction but are not resistant to T1 and T5 phage infection.
MegaX DH10B T1^R Electrocomp Cells have the highest transformation efficiency (>3 x 10¹⁰ cfu/μg plasmid DNA) and also offer the benefit of T1 and T5 phage resistance.

For Research Use Only. Not for use in diagnostic procedures.

Specifications

Antibiotic Resistance BacterialYes (Streptomycin)

Blue/White ScreeningYes (lacZΔM15)

Cloning Methylated DNAYes (mcrA)

Cloning Unstable DNANot suitable for cloning unstable DNA

Contains F' EpisomeNo

High-throughput CompatibilityLow

Improves Plasmid QualityYes (endA1)

PlasmidMay be used for plasmids >20 kb

Preparing Unmethylated DNANo

Product LineElectroMAX

Product TypeElectrocompetent Cells

Quantity5 x 100 μL

Reduces RecombinationYes (recA1)

Shipping ConditionDry Ice

T1 Phage - Resistant (tonA)Yes

Transformation Efficiency LevelHigh Efficiency (>1 x 10⁹ cfu/μg)

FormatTube

SpeciesE. coli (K12)

Unit SizeEach

Contents & Storage

• ElectroMAX DH10B T1 Phage-Resistant Cells (5 x 100 μL)
Store Competent Cells at –80°C.

• pUC19 DNA (50 μL at 10 pg/μL)
Store pUC19 DNA at –20°C.

• S.O.C. Medium (2 x 6 mL)
Store S.O.C. Medium at 4°C or room temperature.

.

Frequently asked questions (FAQs)

How do you recommend that I prepare my DNA for successful electroporation of E. coli?

For best results, DNA used in electroporation must have a very low ionic strength and a high resistance. A high-salt DNA sample may be purified by either ethanol precipitation or dialysis.

The following suggested protocols are for ligation reactions of 20ul. The volumes may be adjusted to suit the amount being prepared.

Purifying DNA by Precipitation: Add 5 to 10 ug of tRNA to a 20ul ligation reaction. Adjust the solution to 2.5 M in ammonium acetate using a 7.5 M ammonium acetate stock solution. Mix well. Add two volumes of 100 % ethanol. Centrifuge at 12,000 x g for 15 min at 4C. Remove the supernatant with a micropipet. Wash the pellet with 60ul of 70% ethanol. Centrifuge at 12,000 x g for 15 min at room temperature. Remove the supernatant with a micropipet. Air dry the pellet. Resuspend the DNA in 0.5X TE buffer [5 mM Tris-HCl, 0.5 mM EDTA (pH 7.5)] to a concentration of 10 ng/ul of DNA. Use 1 ul per transformation of 20 ul of cell suspension.

Purifying DNA by Microdialysis: Float a Millipore filter, type VS 0.025 um, on a pool of 0.5X TE buffer (or 10% glycerol) in a small plastic container. Place 20ul of the DNA solution as a drop on top of the filter. Incubate at room temperature for several hours. Withdraw the DNA drop from the filter and place it in a polypropylene microcentrifuge tube. Use 1ul of this DNA for each electrotransformation reaction.

When should DMSO, formamide, glycerol and other cosolvents be used in PCR?

Cosolvents may be used when there is a failure of amplification, either because the template contains stable hairpin-loops or the region of amplification is GC-rich. Keep in mind that all of these cosolvents have the effect of lowering enzyme activity, which will decrease amplification yield. For more information see P Landre et al (1995). The use of co-solvents to enhance amplification by the polymerase chain reaction. In: PCR Strategies, edited by MA Innis, DH Gelfand, JJ Sninsky. Academic Press, San Diego, CA, pp. 3-16.

Additionally, when amplifying very long PCR fragments (greater than 5 kb) the use of cosolvents is often recommended to help compensate for the increased melting temperature of these fragments.

Find additional tips, troubleshooting help, and resources within our PCR and cDNA Synthesis Support Center.

Citations & References (4)

Citations & References

Abstract

McrA and McrB restriction phenotypes of some E. coli strains and implications for gene cloning.

Authors:Raleigh EA, Murray NE, Revel H, Blumenthal RM, Westaway D, Reith AD, Rigby PW, Elhai J, Hanahan D,

Journal:Nucleic Acids Res

PubMed ID:2831502

'The McrA and McrB (modified cytosine restriction) systems of E. coli interfere with incoming DNA containing methylcytosine. DNA from many organisms, including all mammalian and plant DNA, is expected to be sensitive, and this could interfere with cloning experiments. The McrA and B phenotypes of a few strains have been ... More

Quantitative evaluation of Escherichia coli host strains for tolerance to cytosine methylation in plasmid and phage recombinants.

Authors:Woodcock DM, Crowther PJ, Doherty J, Jefferson S, DeCruz E, Noyer-Weidner M, Smith SS, Michael MZ, Graham MW,

Journal:Nucleic Acids Res

PubMed ID:2657660

Many strains of E. coli K12 restrict DNA containing cytosine methylation such as that present in plant and animal genomes. Such restriction can severely inhibit the efficiency of cloning genomic DNAs. We have quantitatively evaluated a total of 39 E. coli strains for their tolerance to cytosine methylation in phage ... More

Properties of the FhuA channel in the Escherichia coli outer membrane after deletion of FhuA portions within and outside the predicted gating loop.

Authors:Killmann H, Benz R, Braun V,

Journal:J Bacteriol

PubMed ID:8955314

Escherichia coli transports Fe3+ as a ferrichrome complex through the outer membrane in an energy-dependent process mediated by the FhuA protein. A FhuA deletion derivative lacking residues 322 to 355 (FhuA delta322-355) forms a permanently open channel through which ferrichrome diffused. This finding led to the concept that the FhuA ... More

Differential plasmid rescue from transgenic mouse DNAs into Escherichia coli methylation-restriction mutants.

Authors:Grant SG, Jessee J, Bloom FR, Hanahan D,

Journal:Proc Natl Acad Sci U S A

PubMed ID:2162051

Plasmids comprising transgene insertions in four lines of transgenic mice have been retrieved by plasmid rescue into a set of Escherichia coli strains with mutations in different members of the methylation-dependent restriction system (MDRS). Statistical analysis of plasmid rescue frequencies has revealed that the MDRS loci detect differential modifications of ... More