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.
Highlights
Grow plasmids free of Dam and Dcm methylation
Free of animal products
Phage T1 resistant (fhuA31)
Activity of nonspecific endonuclease I (endA1) eliminated for highest quality plasmid preparations
Effect of heat shock time on dam-/dcm-competent E. coli transformation efficiency:
50 μl of competent cells were transformed with 100 pg of pUC19 control DNA following the provided High Efficiency Transformation Protocol except heat shock time varied from 0 to 80 seconds.Effect of DNA incubation time on dam-/dcm- competent E. coli transformation efficiency: 50 μl of competent cells were transformed with 100 pg of pUC19 control DNA following the provided High Efficiency Transformation Protocol except DNA incubation time varied from 0 to 40 minutes.Effect of outgrowth medium on transformation efficiency: 50 μl of -/dcm-competentE.coli was transformed with 100 pg of pUC19 control DNA following the provided High Efficiency Transformation Protocol with the exception of varying the outgrowth medium. NEB SOC outgrowth medium delivers the highest transformation efficiency.
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.
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The Certificate of Analysis (COA) is a signed document that includes the storage temperature, expiration date and quality controls for an individual lot. The following file naming structure is used to name these document files: [Product Number]_[Size]_[Version]_[Lot Number]
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