BL21(DE3) Competent E. coli

• 产品编号：C2527I      品牌：New England Biolabs       原厂货号：C2527I
• 产品分类：克隆 > 克隆载体和克隆试剂盒 > 细菌菌株和感受态细胞 > 感受态细胞
• 应用分类：

描述：

• Transformation efficiency: 1–5 x 10⁷ cfu/µg pUC19 DNA
• T7 Expression Strain
• Deficient in proteases Lon and OmpT
• Resistant to phage T1 (fhuA2)
• B Strain
• Free of animal products

Description:
Chemically competent E. coli cells suitable for transformation and protein expression.

Reagents Supplied:
C2527H
20 x 0.05 ml/tube of chemically competent BL21(DE3) Competent E.coli cells (Store at -80°C)
20 ml of SOC Outgrowth Medium (Store at room temperature)
0.025 ml of 50 pg/µl pUC19 Control DNA (Store at -20°C)

C2527I
6 x 0.2 ml/tube of chemically competent BL21(DE3) Competent E. coli cells (Store at -80°C)
25 ml of SOC Outgrowth Medium (Store at room temperature)
0.025 ml of 50 pg/µl pUC19 Control DNA (Store at -20°C)

Genotype:
fhuA2 [lon] ompT gal (λ DE3) [dcm] ∆hsdS
λ DE3 = λ sBamHIo ∆EcoRI-B int::(lacI::PlacUV5::T7 gene1) i21 ∆nin5

Transformation Protocol Variables:
Thawing: Cells are best thawed on ice and DNA added as soon as the last bit of ice in the tube disappears. Cells can also be thawed by hand, but warming above 0°C will decrease the transformation efficiency.

Incubation of DNA with Cells on Ice: For maximum transformation efficiency, cells and DNA should be incubated together on ice for 30 minutes. Expect a 2-fold loss in transformation efficiency for every 10 minutes you shorten this step.

Heat Shock: Both the temperature and the timing of the heat shock step are important and specific to the transformation volume and vessel. Using the transformation tube provided, 10 seconds at 42°C is optimal.

Outgrowth: Outgrowth at 37°C for 1 hour is best for cell recovery and for expression of antibiotic resistance. Expect a 2-fold loss in transformation efficiency for every 15 minutes you shorten this step. SOC gives 2-fold higher transformation efficiency than LB medium; and incubation with shaking or rotating the tube gives 2-fold higher transformation efficiency than incubation without shaking.

Plating: Selection plates can be used warm or cold, wet or dry without significantly affecting the transformation efficiency. However, warm, dry plates are easier to spread and allow for the most rapid colony formation.

原厂资料：

注意事项：

CAUTION: This product contains DMSO, a hazardous material. Review the MSDS before handling.

General notes:

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