Competent Cells Selection Guide

All Epicentre Competent Cells have the following features:

Endonuclease minus (endA 1)	Endonuclease A is a DNase that can survive boiling lysis and can degrade plasmid DNA, reducing the DNA yield from plasmid purifications.
lacZΔM15	A deletion in the lacZ gene which codes for part of the amino-terminal of the β-galactosidase enzyme. A plasmid containing sequences of the amino terminus can complement this deletion to give functional β-galactosidase. When X-gal is used as the substrate, β-galactosidase produces a blue product; the colonies of these cells appear blue. When the complimentary sequence on the vector is disrupted by inserting a cloned fragment of DNA, the enzyme is no longer functional and cannot produce a blue product; the colonies of these cells are white. On a plate of mixed blue and white colonies, the white colonies should contain the cloned DNA.
Recombination minus (recA 1)	The recA gene codes for a DNA-dependent ATPase that is essential for genetic recombination in E. coli. Bacterial strains deficient in recA are defective in recombination. Plasmids in these strains are maintained as monomers (do not form multimeric circles) and are less likely to incur deletions.
Restriction minus (mcrA, Δ[mrr-hsdRMS-mcrBC])	Restriction systems are designed to protect bacterial cells from foreign DNA. Deleting the host cells’ restriction system allows efficient cloning of DNA with different methylation patterns, such as DNA found in mammals, higher plants, and many prokaryotes.

 

Electrocompetent E. coli

Strain Name	T1 & T5 Phage Resistant	Catalog Number	Transformation Efficiency (cfu/µg pUC19)	Used with Specific Vector Ori	Accepts Large DNA	Applications
TransforMax™ EC100™	No	EC10005 5 x 100µlEC10010 10 x 100µl	>1 X 1010	No	145 kb	General Purpose
TransforMax™ EC100™-T1R	Yes	EC0205T1 5 x 100 µl	>1 X 1010	No	145 kb	General Purpose
TransforMax™ EC100D™ pir+	No	ECP09500 5 x 100 µl	>5 X 109	R6Kγori 15 copies/cell	Up to 100 kb	Rescue cloning using EZ-Tn5™ or HyperMu™ Transposome™ Complexes
TransforMax™ EC100D™ pir-116	No	EC6P095H 5 x 100 µl	>5 X 109	R6Kγori 250 copies/cell	Up to 50 kb	Rescue cloning using EZ-Tn5™ or HyperMu™ Transposome™ Complexes
TransforMax™ EPI300™	No	EC300110 10 x 100µlEC300150 50 x 100µl	>1 X 1010	Vectors containing both F-factor and oriV replicons	At least 145 kbGood for Libraries	Use with CopyControl™ Vectors for inducible single to multiple copies/cellClone toxic genes and unstable DNA
TransforMax™ EPI300™-T1R	Yes	EC02T15 5 x 100µlEC02T110 10 x 100µl	>1 X 1010	Vectors containing both F-factor and oriV replicons	At least 145 kbGood for Libraries	Use with CopyControl™ Vectors for inducible single to multiple copies/cellClone toxic genes and unstable DNA
CopyCutter™ EPI400™	Yes	C400EL10 10 x 50 µl	>1 X 1010	ColE1-type replicons	145 kb	Controls copy number of common vectorsClone toxic genes and unstable DNA

Note: Catalogue number EC10005, EC0205T1 and EC02T15 have been discontinued, effective from August 2014. These products are available only until stocks last.

 

Chemically Competent E. coli

Strain Name	T1 & T5 Phage Resistant	Catalog Number	Transformation Efficiency (cfu/µg pUC19)	Used with Specific Vector Ori	Accepts Large DNA	Applications
TransforMax™ EC100™	No	CC02810 10 x 50 µl	>1 X 108	No	At least 23 kb	General Purpose
TransforMax™ EC100™-T1R	Yes	CCT10210 10 x 50 µl	>5 X 107	No	At least 23 kb	General Purpose
TransforMax™ EPI300™	No	C300C105 10 x 50 µl	>5 X 108	Vectors containing both F-factor and oriV replicons	At least 23 kb	Use with CopyControl™ Vectors for inducible single to multiple copies/cellClone toxic genes and unstable DNA
TransforMax™ EPI300™-T1R	Yes	CT1C0210 10 x 50 µl	>5 X 108	Vectors containing both F-factor and oriV replicons	At least 23 kb	Use with CopyControl™ Vectors for inducible single to multiple copies/cellClone toxic genes and unstable DNA
CopyCutter™ EPI400™	Yes	C400CH10 10 x 50 µl	>1 X 107	ColE1-type replicons	At least 23 kb	Controls copy number of common vectorsClone toxic genes and unstable DNA

Note: Catalogue number CT1C0210 has been discontinued, effective from August 2014. This product will be available only until stocks last.