For simple, high efficiency transformations without heat shock and lengthy incubations.


  • Simple 20 Second Transformation: No heat shock! Just add DNA and spread on plate.
  • High Transformation Efficiencies: Achieve 108 – 109 per µg of plasmid DNA.
  • Versatile: Excellent for general cloning, blue-white screening, and plasmid isolation.


The Mix & Go! E. coli strains are premade, chemically competent cells for simple and highly efficient DNA transformation. Mix & Go! E. coli cells are made chemically competent by a method that completely eliminates the need for heat shocking and related procedures. For transformation, simply mix DNA with cells and then spread onto solid medium – Mix & Go! The premade Mix & Go! competent cells are highly efficient (> 108 transformants/ µg pUC19) and can be used for cloning, sub-cloning, PCR fragment cloning, library construction, etc.

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Technical Specifications

Additional Info Partly restriction-deficient; good strain for cloning repetitive DNA (recA-). Suppresses many amber mutations when glutamine is available but not the S100 or S7 mutation of ?, e.g.,?gt11. Can be used for M13 cloning/sequencing and blue/white screening.
Genotype F`[traD36 proA+B+ laclq ?(lacZ)M15] ?(lac-proAB) glnV44 (supE44) e14- (McrA-) thi gyrA96 (NalR) endA1 hsdR17(rk- mk+) relA1 recA1
Processing Time 20 Seconds
Product Storage -70°C to -80°C
Transformation Efficiency 108 – 109 transformants per µg of plasmid DNA

Product FAQ:

Product FAQ

Q1: Are competent cells GMOs?

All our competent cells are classified into Biosafety level 1 and are not genetic modified organisms. Only when transformed with a plasmid they become GMOs.

Q2: Are the Mix & Go! strains dam+ and dcm+?

Most cloning strains will be dam+/dcm+ unless specifically noted in the genotype.

Q3: Do the Mix & Go! strains methylate DNA?


Q4: Which strains are equivalent to the Zymo strains?

DH5a is equivalent to Zymo 5a. DH10B, Top10, and One Shot Top10 are equivalent to Zymo 10B. For XL-21 Blue, JM109 is the closest match and for Stbl3, HB101 is the closest match.

Q5: How to reduce satellite colonies on agar plates?

– Prepare fresh agar plates
– Use more antibiotics in plates
– Incubate plates for a shorter time after plating cells

Q6: Is it possible to dilute the competent cells?

We do not recommend diluting the competent cells. We recommend using less DNA to transform cells, or aliquot cells in smaller volumes before transformation. If absolutely necessary, cold 1X Competent Buffer (Mix & Go Transformation Kit, T3001 & T3002) should be used in the dilution.

Q7: Which antibiotics can be used with the Mix & Go! procedure?

No outgrowth is necessary when using Ampicillin or Carbenicillin for selection. However, an outgrowth step is required when using Chloramphenicol, Kanamycin, and Tetracycline because of the mode of action of the antibiotic itself.

We recommend the following procedure for the outgrowth step:

1. Incubate cells on ice for 5-10 min after addition of plasmid

2. Add 4 volumes of SOC media

3. Incubate at 37°C for 60 min with gentle shaking at 200-300 rpm

4. Spread on a pre-warmed culture plate containing the appropriate antibiotic

Q8: Which Plasmid Size can be used for transformation?

For Zymo 5a and Zymo 10B up to 20kb. However, transformation efficiency decreases proportionally from 10-20kb. Above 20kb, cells are difficult to transform. JM109, HB101, XJa, XJa (DE3), XJb, XJb (DE3) and TG1 can handle constructs up to 10kb.

Q9: Which is the recommended DNA concentration and volume for transformation?

There really is no maximum or minimum recommended DNA concentration, but we use 10 pg for quality control. However, the volume of DNA added should not exceed 5% of the cells total volume; the efficiency can decrease several fold as the volume of DNA used increases. If the DNA sample is too diluted, use our DNA Clean & Concentrator.

Q10: What are some tips to improve transformation efficiency?

1. Thaw cells on ice, not room temperature.

2. Incubate cells and DNA mixture on ice, not at room temperature.
However, do not incubate longer then 1 hour.

3. Ensure cells are still frozen when received.

4. Pre-warm the culture plates at 37°C for at least 30 minutes.

5. Prepare fresh LB agar plates containing the appropriate antibiotic.

6. Prepare a new DNA sample.

7. Store the cells at -80°C (not 4°C or -20°C). If the freezer breaks, the cells should be OK as long as the temp does not go higher than -50°C.

8. Avoid freeze/thaw cycles.

Q11: How will a heat-shock affect my Transformation Efficiency?

Heat shock is not necessary, however sometimes it can be beneficiary when preparing libraries or transforming XJb Autolysis E. coli strains.

We recommend the following protocol for Heat Shock with Outgrowth:

1. Incubate cells on ice for 5-10 min after addition of plasmid.

2. Incubate cells at 42°C for 45 seconds.

3. Add 450 ml of SOC to the cells.

4. Incubate at 37°C for 60 min with gentle shaking at 200-300 rpm.

5. Spread on a pre-warmed culture plate containing the appropriate antibiotic.


Mix & Go! Competent Cells -JM109

Cat # Name Size
T3003 Mix and Go! Competent Cells -JM109 10 x 100 µl
T3005 Mix and Go! Competent Cells -JM109 96 x 50 µl