Product Class: Competent Cell

NEB 5-alpha F'Iq Competent E. coli (High Efficiency)

No dry ice charges with competent cells
Catalog #SizeConcentration
C2992I6 x 0.2 ml/tube
C2992H20 x 0.05 ml/tube

Description

Highlights

  • DH5α™ derivative
  • Free of animal products
  • Transformation efficiency 1-3 x 109 cfu/µg pUC19 DNA
  • Efficient transformation of unmethylated DNA derived from PCR, cDNA and many other sources (hsdR)
  • Tight control of expression by laclq allows potentially toxic genes to be cloned
  • Activity of nonspecific endonuclease I (endA1) eliminated for highest quality plasmid preparations
  • Resistance to phage T1 (fhuA2)
  • Suitable for blue/white screening by α-complementation of the β-galactosidase gene
  • F' allows cells to be infected with bacteriophage M13 for ssDNA production
  • Reduced recombination of cloned DNA (recA1)
  • K12 Strain
Chemically competent E. coli cells suitable for high efficiency transformation in a wide variety of applications.

Features

  • Toxic gene cloning
  • F´ strain with extremely high transformation efficiency

Genotype

proA+B+ lacIq ∆(lacZ)M15 zzf::Tn10 (TetR) / fhuA2∆(argF-lacZ)U169 phoA glnV44 Φ80Δ(lacZ)M15 gyrA96 recA1 relA1 endA1 thi-1 hsdR17

Reagents Supplied

The following reagents are supplied with this product:

Store at (°C)Concentration
pUC19 Transformation Control Plasmid-200.05 ng/μl
SOC Outgrowth Medium41X

Advantages and Features

Applications


DNA Effects on Transformation Efficiency and Colony Output: The optimal amount of DNA to use in a transformation reaction is lower than commonly recognized. Using clean, supercoiled pUC19, the efficiency of transformation is highest in the 100 pg-1 ng range. However, the total colonies which can be obtained from a single transformation reaction increase up to about 100 ng.
Effect of heat shock time on NEB 5-alpha F´Iq 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 NEB 5-alpha F´Iq 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 NEB 5-alpha F´Iq competent E.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.
Effect of Plasmid Size on Transformation Efficiency: NEB 10-beta chemically competent cells are more efficiently transformed with large plasmids than NEB 5-alpha F´Iq cells. The difference in TE between the two cell lines increases with the size of the plasmid being transformed.

Properties and Usage

Antibiotics for Plasmid SelectionWorking Concentration
Ampicillin100 μg/ml
Carbenicillin100 μg/ml
Chloramphenicol33 μg/ml
Kanamycin30 μg/ml
Streptomycin25 μg/ml

Storage Temperature

-80°C

Shipping Notes

  • Ships on dry ice

Quality Control

Quality Control Assays

The 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.

Supporting Documents

Material Safety Datasheets

The following is a list of Material Safety Data Sheets (MSDS) that apply to this product to help you use it safely. The following file naming structure is used to name these document files: [Product Name] MSDS. For international versions please contact us at info@neb.com.

Datacards

The Product Summary Sheet, or Data Card, includes details for how to use the product, as well as details of its formulation and quality controls. The following file naming structure is used to name the majority of these document files: [Catalog Number]Datasheet-Lot[Lot Number]. For those product lots not listed below, please contact NEB at info@neb.com or fill out the Technical Support Form for appropriate document.

Notes

  1. CAUTION: This product contains DMSO, a hazardous material. Review the MSDS before handling.
  2. 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.
  1. Does plasmid size affect transformation efficiency (C2992)?
  2. How long should I incubate cells on ice after DNA has been added (NEB #C2992H and NEB #C2992I)?
  3. How should I calculate the transformation efficiency (C2992)?
  4. What are the solutions/recipes (C2992)?
  5. What are the strain properties (C2992)?
  6. What is the difference between NEB #C2992H and NEB #C2992I?
  7. What is the optimal heat shock time for this strain (NEB #C2992H and NEB #C2992I)?
  8. Which strain of Competent E. coli should I use for general cloning?
  9. Can I store competent cells at -20°C instead of -80°C?
  10. Which kind of transformation tubes should be used?
  11. What volume of DNA can be added into competent cells?
  12. What is the shelf life for this strain (NEB #C2992H and NEB #C2992I)?
  13. Are NEB's competent cells compatible with the "Plate and Go" protocol?
  1. High Efficiency Transformation Protocol (C2992)
  2. 5 Minute Transformation Protocol (C2992)

Selection Tools

Usage Guidelines & Tips

Application Notes