S.O.C. Medium
S.O.C. Medium
Invitrogen™

S.O.C. Medium

S.O.C. (Super Optimal broth with Catabolite repression) Medium is used in the final step of bacterial cell transformation to obtainRead more
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Catalog number 15544034
Price (USD)
142.00
Each
Add to cart
Price (USD)
142.00
Each
Add to cart

S.O.C. (Super Optimal broth with Catabolite repression) Medium is used in the final step of bacterial cell transformation to obtain maximal transformation efficiency of E. coli. Catabolite repression is achieved by providing glucose in the medium and thus creating optimal metabolic conditions for E. coli. In addition, high nutrient concentration allows cells to recover after the stress induced by transformation and achieve 2–3 fold higher efficiency as compared to recovery in LB medium.

S.O.C. Medium formulation
Composition: 2% tryptone, 0.5% yeast extract, 10 mM NaCl, 2.5 mM KCl, 10 mM MgCl2, 10 mM MgSO4, and 20 mM glucose.
S.O.C. medium has the same formulation as the rich S.O.B. (Super Optimal Broth) medium with additionally added 10 mM MgCl2 and 20 mM glucose (as published by Hanahan in 1983).

Convenient, ready-to-use format
S.O.C. Medium is supplied as 10 x 10 mL bottles of ready-to-use liquid medium. 

Quality testing
Each lot of S.O.C. Medium is tested to ensure conformance with the most current approved product specifications. This currently consists of tests for pH, osmolality, sterility, and transformation efficiency using TOP10 E. coli.

Find the media format that fits your needs
We offer many ready-to-use media formulations, such as LB Broth and Terrific Broth.
Explore other media formats for bacterial growth.

For Research Use Only. Not for use in diagnostic procedures.
Specifications
SpeciesEscherichia coli
FormatBottle
Media TypeS.O.C (Super Optimal broth with Catabolite repression)
Preparation MethodReady-to-Use
Product TypeRecovery Medium
SterilitySterile
Target Organism ClassColiforms
Packaging Type10 mL/bottle
Quantity10 x 10 mL bottles
Shipping ConditionApproved for shipment at Room Temperature or on Wet or Dry Ice
Unit SizeEach
Contents & Storage
• 10 x 10 mL bottles S.O.C. Medium

Store at room temperature.

Frequently asked questions (FAQs)

How do you recommend that I prepare my DNA for successful electroporation of E. coli?

For best results, DNA used in electroporation must have a very low ionic strength and a high resistance. A high-salt DNA sample may be purified by either ethanol precipitation or dialysis.

The following suggested protocols are for ligation reactions of 20ul. The volumes may be adjusted to suit the amount being prepared.

Purifying DNA by Precipitation: Add 5 to 10 ug of tRNA to a 20ul ligation reaction. Adjust the solution to 2.5 M in ammonium acetate using a 7.5 M ammonium acetate stock solution. Mix well. Add two volumes of 100 % ethanol. Centrifuge at 12,000 x g for 15 min at 4C. Remove the supernatant with a micropipet. Wash the pellet with 60ul of 70% ethanol. Centrifuge at 12,000 x g for 15 min at room temperature. Remove the supernatant with a micropipet. Air dry the pellet. Resuspend the DNA in 0.5X TE buffer [5 mM Tris-HCl, 0.5 mM EDTA (pH 7.5)] to a concentration of 10 ng/ul of DNA. Use 1 ul per transformation of 20 ul of cell suspension.

Purifying DNA by Microdialysis: Float a Millipore filter, type VS 0.025 um, on a pool of 0.5X TE buffer (or 10% glycerol) in a small plastic container. Place 20ul of the DNA solution as a drop on top of the filter. Incubate at room temperature for several hours. Withdraw the DNA drop from the filter and place it in a polypropylene microcentrifuge tube. Use 1ul of this DNA for each electrotransformation reaction.

What is the formulation of the SOC medium that is provided with competent cells?

SOC (Super Optimal Catabolite) Medium Preparation (for 1 Liter):

1) To a 2 Liter flask with stir bar add the following:
- Bacto Tryptone 20 g
- Yeast Extract 5 g
- Sodium Chloride (NaCl) 0.58 g
- Potassium Chloride (KCl) 0.186 g
2) Add sterile water to a final volume of 1 Liter.
3) Mix well on magnetic stir plate for 5-10 minutes or until all of the ingredients are well mixed and completely dissolved.
4) Autoclave 30 minutes.
5) Allow to cool to room temperature.
6) Add 10 ml of sterile 2M Magnesium Solution (1M Magnesium sulfate, 1M Magnesium chloride)and mix well.
7) Add 10 ml of sterile 2M Glucose and mix well. (Final Glucose concentration is 20 mM).

Is S.O.C. medium absolutely required when recovering competent bacterial cells during transformation?

Many media can be used to grow transformed cells, including standard LB, SOB or TB broths. However, S.O.C. is the optimal choice for recovery of the cells before plating. The nutrient-rich formula with added glucose is often important for obtaining maximum transformation efficiencies.

When should DMSO, formamide, glycerol and other cosolvents be used in PCR?

Cosolvents may be used when there is a failure of amplification, either because the template contains stable hairpin-loops or the region of amplification is GC-rich. Keep in mind that all of these cosolvents have the effect of lowering enzyme activity, which will decrease amplification yield. For more information see P Landre et al (1995). The use of co-solvents to enhance amplification by the polymerase chain reaction. In: PCR Strategies, edited by MA Innis, DH Gelfand, JJ Sninsky. Academic Press, San Diego, CA, pp. 3-16.

Additionally, when amplifying very long PCR fragments (greater than 5 kb) the use of cosolvents is often recommended to help compensate for the increased melting temperature of these fragments.

Find additional tips, troubleshooting help, and resources within our PCR and cDNA Synthesis Support Center.