Intact Genomics (ig®) Stable 2 chemically competent E. coli cells are suitable for high efficiency transformation in a wide variety of applications such as cloning and sub-cloning. Stable 2 cells are capable of cloning methylated genomic sequences, retroviral sequences and direct repeat sequences. Intact Genomics Stable 2 cells provide superb transformation efficiency, allowing for increased opportunity for experimental success.
CUSTOM ALIQUOTS AVAILABLE
Specifications
Competent cell type: Chemically competentSpecies: E. coliFormat: TubesTransformation efficiency: ≥1.0 x 109 cfu/µg pUC19 DNABlue/white screening: NoShipping condition: Dry ice
Reagents Needed for One Reaction
ig® Stable 2 chemically competent cells: 50 µlDNA (or pUC19 Control, 10 pg/µl): 1 µlRecovery medium: 1 ml
Product Includes & Storage
ig® Stable 2 chemically competent cells: -80 ºCpUC19 control DNA: -20 ºCRecovery medium: 4 ºC
Product Benefits
ig® Stable 2 chemically competent cells have the following features:
- Stable 2 allows for cloning of methylated genomic sequences
- Stabilizes retroviral and direct repeat sequences including HIV
- High transformation efficiency allows aids in cloning rare sequences
- May be used for plasmids > 20 kb
- endA1 mutation increases plasmid yield significantly
Genotype
F- mcrA Δ(mcrBC-hsdRMS-mrr) recA1 endA1lon gyrA96 thi supE44 relA1 λ- Δ(lac-proAB)
Quality Control
Transformation efficiency is tested by using the pUC19 control DNA supplied with the kit and the high efficiency transformation protocol listed below. Transformation efficiency should be ≥1 x 109 CFU/µg pUC19 DNA.
Untransformed cells are tested for appropriate antibiotic sensitivity.
General Guidelines
Follow these guidelines when using ig® Stable 2 chemically competent E. coli.
- Handle competent cells gently as they are highly sensitive to changes in temperature or mechanical lysis caused by pipetting.
- Thaw competent cells on ice, and transform cells immediately following thawing. After adding DNA, mix by tapping the tube gently. Do not mix cells by pipetting or vortexing.
Example Calculation of Transformation EfficiencyTransformation Efficiency (TE) is defined as the number of colony forming units (cfu) produced by transforming 1µg of plasmid into a given volume of competent cells.
TE = Colonies/µg/Dilution
Transform 1 µl of (10 pg/µl) pUC19 control plasmid into 50 µl of cells, add 950 µl of Recovery Medium. Dilute 10 µl of this in 990 µl of Recovery Medium and plate 50 µl. Count the colonies on the plate the next day. If you count 100 colonies, the TE is calculated as follows:
Colonies = 100µg of DNA = 0.00001Dilution = 50/1000 x 10/1000 = 0.0005TE = 100/.00001/.0005 = 2.0×10101016-12 1016-24
