Invitrogen™

One Shot™ BL21-AI™ Chemically Competent E. coli

One Shot BL21-AI Chemically Competent E. coli cells are designed for applications that require tight regulation and strong expression of자세히 알아보기

One Shot BL21-AI Chemically Competent E. coli cells are designed for applications that require tight regulation and strong expression of toxic proteins from any T7-promoter-based expression systems. A derivative of the E. coli B strain, BL21-AI does not contain the lon protease and is deliberately deficient in the outer membrane protease OmpT.

The lack of two key proteases reduces degradation of heterologous proteins expressed in the strain. Additionally, several other strain features make these cells especially well suited for protein production, namely fast growth in minimal medium, a lower acetate production when grown in high glucose media, and the ability to reach high cell density.

BL21-AI E. coli contain a chromosomal insertion of a cassette containing the T7 RNA polymerase (T7RNAP) into the _ara_B locus of the _ara_BAD operon, placing regulation of T7 RNAP under the control of the arabinose-inducible _ara_BAD promoter. The _ara_B gene is deleted in this strain. The presence of the _tet_A gene confers resistance to tetracycline and permits verification of strain identity using tetracycline. The yield of recombinant protein obtained from BL21-AI is generally similar to that obtained from BL21 (DE3). BL21-AI, due it`s qualities and genomic background, was used to elucidate fundamental steps in the adaptation process of the CRISPR/Cas system. One Shot BL21-AI Chemically Competent cells have a transformation efficiency of >1 x 108 cfu/μg plasmid DNA.

One Shot BL21-AI Chemically Competent E. coli offer:
• Transformation efficiency of >1 x 108 cfu/μg control plasmid DNA
• Ion and OmpT protease deficiency that reduces degradation of recombinant protein
• T7 RNA polymerase controlled by the tightly regulated arabinose-inducible _ara_BAD promoter
• _hsd_S mutation that allows efficient transformation of unmethylated DNA
• Ideal for inducing expression of toxic protein from any T7 promoter-based plasmid

Easy-to-use One Shot format
BL21-AI Chemically Competent E. coli cells are supplied in the convenient, single-reaction One Shot format. The single-tube, single-use format allows all steps of the transformation protocol, up to plating, to take place in the same tube, thereby helping save time and prevent contamination.

Genotype
F–_omp_T _hsd_SB (rB–, mB–) _gal dcm ara_B::T7RNAP-_tet_A

Find the strain and format that fits your needs
We offer several E. coli strains for protein expression.
BL21 Star (DE3) and other strains are available in MultiShot formats for high throughput applications.
Explore bacterial growth media formats.
We offer a variety of systems for the expression of recombinant proteins in E. coli. The Champion pET expression system provides the highest level of protein production available in any expression system.

Notes
• To induce expression from the _ara_BAD promoter, use L-arabinose. To repress basal expression from the _ara_BAD promoter, use glucose. Even if glucose is absent, basal expression from is generally low.
• BL21-AI strain genome sequences available in the NCBI GenBank database under accession number CP047231 (Bhawsinghka et al. 2020).

사양

제품 유형Chemically Competent Cells

에프에피솜 포함No

플라스미드 품질 개선No

메틸화 DNA 클로닝No

형질전환 효율 수준Medium Efficiency (1 x 108 to 1 x 109 cfu/μg)

항생제 내성 박테리아Yes (Tetracycline)

블루/화이트 스크리닝No

고처리량 호환성Low

비메틸화 DNA 준비Yes (dcm)

재조합 감소No

배송 조건Dry Ice

T1 Phage - 저항성(tonA)No

종E. coli (B)

프로모터T7

형식Tube

제품라인One Shot™

수량21 x 50 μL/tube

Toxic ProteinsYes (araB)

Improves RNA StabilityNo

Improves Protein StabilityYes (lon, ompT)

Unit SizeEach