- Grow plasmids free of Dam and Dcm methylation
- Free of animal products
- Phage T1 resistant (fhuA31)
- Transformation efficiency: 1-3 x 106 cfu/μg pUC19 DNA
- Activity of nonspecific endonuclease I (endA1) eliminated for highest quality plasmid preparations
- K12 Strain
Methyltransferase deficient chemically competent E. coli cells suitable for growth of plasmids free of Dam and Dcm methylation. Note that dam- strains are not recommended as a host for primary cloning/ligation. The dam mutation can result in an increased mutation rate in the cell and a reduction in the transformation efficiency. DNA should be maintained in a dam+ strain unless there is a specific need for DNA free of Dam or Dcm methylation.
- Dam/Dcm methyltransferase free plasmid growth
Genotypeara-14 leuB6 fhuA31 lacY1 tsx78 glnV44 galK2 galT22 mcrA dcm-6 hisG4 rfbD1 R(zgb210::Tn10) TetS endA1 rspL136 (StrR) dam13::Tn9 (CamR) xylA-5 mtl-1 thi-1 mcrB1 hsdR2
The following reagents are supplied with this product:
|pUC19 Transformation Control Plasmid||0.05 ng/μl|
|SOC Outgrowth Medium||1X|
Advantages and Features
Properties and Usage
|Antibiotics for Plasmid Selection||Working Concentration|
- Ships on dry ice
Quality Control AssaysThe following Quality Control Tests are performed on each new lot and meet the specifications designated for the product. Individual lot data can be found on the Product Summary Sheet/Datacard or Manual which can be found in the Supporting Documents section of this page.
- Transformation Efficiency:
The competent cells are tested for transformation efficiency and pass minimum release criteria. Transformation efficiency is defined as the number of colony forming units (cfu) which would be produced by transforming 1 μg of plasmid into a given volume of competent cells.
Material Safety Datasheets
- CAUTION: This product contains DMSO, a hazardous material. Review the MSDS before handling.
- STORAGE AND HANDLING: Competent cells should be stored at -80°C. Storage at -20°C will result in a significant decrease in transformation efficiency. Cells lose efficiency whenever they are warmed above -80°C, even if they do not thaw.
- Can I transform unmethylated DNA into dam-/dcm- competent E.coli (C2925)?
- Does New England Biolabs offer a methyltransferase free strain of Competent E.coli?
- How long should I incubate cells on ice after DNA has been added (NEB #C2925H and NEB #C2925I)?
- Is dam-/dcm- (NEB #C2925H/C2925I) resistant to kanamycin?
- Is the DNA yield lower using dam-/dcm- strain (C2925)?
- What are the solutions/recipes (C2925)?
- What are the strain properties (C2925)?
- What is the difference between NEB #C2925H and NEB #C2925I?
- What is the optimal heat shock time for this strain (NEB #C2925H and NEB #C2925I)?
- Which strain of Competent E. coli should I use for general cloning?
- Why were the colonies at different size after transformation of dam-/dcm- competent E.coli (C2925)?
- How should I calculate the transformation efficiency (C2925)?
- Can I store competent cells at -20°C instead of -80°C?
- Which kind of transformation tubes should be used?
- What volume of DNA can be added into competent cells?
- What is the shelf life for this strain (NEB #C2925H and NEB #C2925I)?
- Are NEB's competent cells compatible with the "Plate and Go" protocol?