Home Competent Cells Products NEB^® 5-alpha Competent E. coli (High Efficiency)

NEB^® 5-alpha Competent E. coli (High Efficiency)

NEB 5-alpha Competent E. coli is a derivative of the popular DH5α. It is T1 phage resistant and endA deficient for high-quality plasmid preparations.

High efficiency strain ideal for a wide variety of applications
Available in a wide variety of sizes, including single-use vials, 200 μl vials, 96- and 384- well plate and 12 x 8 tube strips
No dry ice surcharge on competent cell shipments
Outgrowth medium included
Free of animal products

Catalog #	Concentration	Size	List Price	Your Price
C2987H	Not Applicable	20 x 0.05 ml	$207.00	Sign In Sign In
C2987I	Not Applicable	6 x 0.2 ml	$159.00	Sign In Sign In
C2987P	Not Applicable	1 96-well plate (20 μl/well)	$523.00	Sign In Sign In
C2987R	Not Applicable	1 384-well plate (10 μl/well)	$1,144.00	Sign In Sign In
C2987U	Not Applicable	96 x 0.05 ml (12 8-well strip)	$778.00	Sign In Sign In

Please enter a quantity for at least one size

Product Information

Chemically competent E. coli cells suitable for high efficiency transformation in a wide variety of applications. Available in 5 convenient formats:

Single-use 50 μl vials
200 μl vials
96-well plate
384-well plate
12 x 8-tube strips: packed in 12 x 8-Strip Microplate Cluster Tube (Costar™ Cluster Tube System)

For C2987H, C2987I, C2987P and C2987U, SOC Outgrowth Medium is provided.
For C2987R, Outgrowth Medium 1.5 is provided.

Highlights

DH5α™ derivative
Free of animal products
Efficient transformation of unmethylated DNA derived from PCR, cDNA and many other sources (hsdR)
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
Reduced recombination of cloned DNA (recA1)
K12 Strain

Transformation Efficiency

For C2987H, C2987I, C2987P and C2987U: 1 - 3 x 10⁹ cfu/μg pUC19 DNA
For C2987R: 1 - 5 x 10⁸ cfu/μg pUC19 DNA

Genotype

fhuA2Δ(argF-lacZ)U169 phoA glnV44 Φ80Δ(lacZ)M15 gyrA96 recA1 relA1 endA1 thi-1 hsdR17

This product is related to the following categories:: Cloning Competent Cell Strains Products

This product can be used in the following applications:: USER^® Cloning,; Applications of USER® and Thermolabile USER II Enzymes,; High-throughput cloning and automation solutions,

Reagents Supplied

The following reagents are supplied with this product:

NEB # Component Name Component # Stored at (°C) Amount Concentration

C2987H

-80

pUC19 Vector	N3041AVIAL	-20	1 x 0.025 ml	50 pg/µl
SOC Outgrowth Medium	B9020SVIAL	4	1 x 25 ml	Not Applicable
NEB^® 5-alpha Competent E. coli (High Efficiency)	C2987HVIAL	-80	20 x 0.05 ml	Not Applicable

C2987I

-80

pUC19 Vector	N3041AVIAL	-20	1 x 0.025 ml	50 pg/µl
SOC Outgrowth Medium	B9020SVIAL	4	1 x 25 ml	Not Applicable
NEB^® 5-alpha Competent E. coli (High Efficiency)	C2987IVIAL	-80	6 x 0.2 ml	Not Applicable

C2987P

-80

pUC19 Vector	N3041AVIAL	-20	1 x 0.025 ml	50 pg/µl
SOC Outgrowth Medium	B9020SVIAL	4	1 x 25 ml	Not Applicable
NEB^® 5-alpha Competent E. coli (High Efficiency)	C2987PVIAL	-80	1 x 96-well plate (20 μl/well)	Not Applicable

C2987R

-80

NEB^® 5-alpha Competent E. coli (High Efficiency)	C2987RVIAL	-80	1 x 384-well plate (10 μl/well)	Not Applicable
Outgrowth Medium 1.5	B9040AVIAL	4	1 x 10 ml	Not Applicable
pUC19 Vector	N3041AVIAL	-20	1 x 0.025 ml	50 pg/µl

C2987U

-80

SOC Outgrowth Medium	B9020SVIAL	4	2 x 25 ml	Not Applicable
NEB^® 5-alpha Competent E. coli (High Efficiency)	C2987UVIAL	-80	1 x 96 x 0.05 ml (12 8-well strip)	Not Applicable
pUC19 Vector	N3041AVIAL	-20	1 x 0.025 ml	50 pg/µl

Properties & Usage

Antibiotic for Plasmid Selection

Antibiotics for Plasmid Selection	Working Concentration
Ampicillin	100 µg/ml
Carbenicillin	100 µg/ml
Chloramphenicol	33 µg/ml
Kanamycin	30 µg/ml
Streptomycin	25 µg/ml
Tetracycline	15 µg/ml

Shipping Notes

Ships on dry ice

Antibiotic Resistance

none

Advantages and Features
Features
- Versatile cloning strain
- DH5α™ derivative
Application Features

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 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 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 competent E.coli was transformed with 100 pg of pUC19control 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.

Benefit from the high transformation efficiencies of NEB 5-alpha
The transformation efficiencies of NEB 5-alpha and DH5α were compared using each manufacturers' recommended protocols. Values shown are the average of triplicate experiments.
Related Products
Companion Products
- NEB® 5-alpha Competent E. coli (Subcloning Efficiency)
- NEB® 5-alpha F' I^q Competent E. coli (High Efficiency)
Materials Sold Separately
- SOC Outgrowth Medium
Product Notes
1. For C2987H, C2987I, C2987P and C2987U, SOC Outgrowth Medium is provided.
  For C2987R, Outgrowth Medium 1.5 is provided.
2. CAUTION: This product contains DMSO, a hazardous material. Review the MSDS before handling.
3. 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.
  
  SOC medium can be stored at either 4°C or Room Temperature depending on how fast it will be used. Storing at Room Temperature is convenient and adequate for short term usage (weeks to a couple of months). For long term storage, we recommend storing at 4°C. Please note that Outgrowth Medium 1.5 supplied with C2987R (1 x 384 well plate format) must only be stored at Room Temperature or crystals will form.