pBAD/TOPO™ ThioFusion™ Expression Kit
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Invitrogen™

pBAD/TOPO™ ThioFusion™ Expression Kit

The pBAD/TOPO™ ThioFusion™ Expression Kit is designed for one-step cloning and regulated expression of thioredoxin fusion proteins in E. coli(FigureRead more
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Catalog NumberQuantity
K3700120 reactions
Catalog number K37001
Price (USD)
1,406.00
Each
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Quantity:
20 reactions
Price (USD)
1,406.00
Each
Add to cart
The pBAD/TOPO™ ThioFusion™ Expression Kit is designed for one-step cloning and regulated expression of thioredoxin fusion proteins in E. coli(Figure 1). The pBAD/Thio-TOPO™ vector encodes His-Patch thioredoxin as an N-terminal fusion partner. The thioredoxin fusion can significantly increase the solubility of many difficult-to-express proteins and improve the yield of protein production. The vector includes the following additional features (Figure 2):

• The araBAD promoter for tightly regulated expression in E. coli I-activated vector for 5-minute TOPO™ Cloning of Taq-amplified PCR products
• C-terminal polyhistidine (6xHis) tag for purification with nickel-chelating resin and detection with an Anti-His(C-term) Antibody
• C-terminal V5 epitope for detection with an Anti-V5 Antibody
• Enterokinase cleavage site for efficient cleavage of N-terminal fusion tag with EKMax™ Enterokinase
For Research Use Only. Not for use in diagnostic procedures.
Specifications
Antibiotic Resistance BacterialAmpicillin (AmpR)
Bacterial or Yeast StrainTOP10
CleavageEK (Enterokinase) Recognition Site
Constitutive or Inducible SystemInducible
Expression MechanismCell-Based Expression
Expression SystemE. coli
Inducing AgentArabinose
Product TypeLentiviral Expression Kit
Quantity20 reactions
Selection Agent (Eukaryotic)None
VectorpBAD
Cloning MethodTOPO-TA
Product LineTOPO, ThioFusion
PromoteraraBAD
Protein TagHis Tag (6x), V5 Epitope Tag, Thioredoxin
Unit SizeEach
Contents & Storage
Each pBAD/TOPO™ ThioFusion™ Expression Kit contains two boxes and the LMG194 E. coli stab. The pBAD/TOPO™ ThioFusion™ Expression box contains all of the reagents necessary for PCR (except Taq polymerase) including 200 ng of topoisomerase I-activated pBAD/Thio-TOPO™ vector, sterile water, dNTPs, 10X PCR buffer, salt solution, control template and primers, 20% L-arabinose, primers for sequencing or PCR screening, and an expression control plasmid. Store at -20°C. The One Shot™ box contains all of the reagents necessary for transformation including 21 single-use 50 μl aliquots of chemically competent TOP10 E. coli, S.O.C. medium, and pUC19 supercoiled control plasmid. Store the One Shot™ box at -80°C. Store the LMG194 E. coli stab at 2 - 8°C. All components are guaranteed stable for 6 months when properly stored.

Frequently asked questions (FAQs)

How much L-arabinose should I use to induce expression with the pBAD expression system?

While the amount of L-arabinose can vary depending on your expression experiment, we suggest performing a pilot expression experiment with varying amounts of L-arabinose from 0.00002% to 0.2%.

Should I use TOP10 cells or the LMG194 E. coli strain you offer for expression with my pBAD system?

Top10

Advantages:
- Saves time, can go directly from cloning to expression.
- The glycerol stock is more stable because these strains are endA- and recA-.

Disdvantages:
- This strain is not protease-deficient. Therefore, the protein may be degraded.

LMG194

Advantages:
- Grows well in minimal media, except M9.
-Have to transform the plasmid into the cells just for expression.
-RM medium with glucose to ensure low basal level of protein.

Disadvantages:
- Not protease-deficient. Therefore, the protein may be degraded.
- The glycerol stock may not be stable because this cell strain is not recA- or endA-.

What competent cells do you recommend I use for expression with my pBAD expression system?

We recommend using a competent cell strain that is araBADC- and araEFGH+, allowing transportation of L-arabinose, but not metabolizing it. This is important for expression studies, as the level of L-arabinose will be constant inside the cell and will not decrease over time. We offer our TOP10 competent cells, or our LMG194 E. coli strain.

Can you tell me the sequence of primers that can be used in pBAD vectors to sequence my gene of interest?

The pBAD vectors contain a forward and reverse pBAD primer flanking the gene of interest. The sequences are as follows:

pBAD forward primer: 5'-ATGCCATAGCATTTTTATCC-3'

pBAD reverse primer: 5'-GATTTAATCTGTATCAGG-3'

Do you have a list of the cap colors for the pBAD vectors?

Here are the cap colors:

- pBAD/His A: Red

- pBAD/His B: Orange

- pBAD/His C: Yellow

- pBAD/His LacZ: Green

- pBad/gIII A: Yellow

- pBad/gIII B: Green

- pBad/gIII C: Blue

- pBAD/gIII/calmodulin: Purple

Citations & References (7)

Citations & References
Abstract
A protein kinase encoded by the t complex responder gene causes non-mendelian inheritance
Authors:BERNHARD G. HERRMANN, BIRGIT KOSCHORZ, KARIN WERTZ, K. JOHN MCLAUGHLIN* & ANDREAS KISPERT
Journal:Nature
PubMed ID:10647005
'Males heterozygous for the t-haplotype form of mouse chromosome 17 preferentially transmit the t-chromosome to their progeny. Several distorter/sterility loci carried on the t-haplotype together impair flagellar function in all spermatozoa whereas the responder, Tcr, rescues t-sperm but not wild-type sperm. Thus, t-sperm have anadvantage over wild-type sperm in fertilizing ... More
The cathepsin B of Toxoplasma gondii, toxopain-1, is critical for parasite invasion and rhoptry protein processing.
Authors: Que Xuchu; Ngo Huân; Lawton Jeffrey; Gray Mary; Liu Qing; Engel Juan; Brinen Linda; Ghosh Partho; Joiner Keith A; Reed Sharon L;
Journal:J Biol Chem
PubMed ID:12000756
'Cysteine proteinases play a major role in invasion and intracellular survival of a number of pathogenic parasites. We cloned a single copy gene, tgcp1, from Toxoplasma gondii and refolded recombinant enzyme to yield active proteinase. Substrate specificity of the enzyme and homology modeling identified the proteinase as a cathepsin B. ... More
Bacterial cell killing mediated by topoisomerase I DNA cleavage activity.
Authors:Cheng B, Shukla S, Vasunilashorn S, Mukhopadhyay S, Tse-Dinh YC,
Journal:J Biol Chem
PubMed ID:16159875
'DNA topoisomerases are important clinical targets for antibacterial and anticancer therapy. At least one type IA DNA topoisomerase can be found in every bacterium, making it a logical target for antibacterial agents that can convert the enzyme into poison by trapping its covalent complex with DNA. However, it has not ... More
Degradation of corn fiber by Clostridium cellulovorans cellulases and hemicellulases and contribution of scaffolding protein CbpA.
Authors:Koukiekolo R, Cho HY, Kosugi A, Inui M, Yukawa H, Doi RH,
Journal:Appl Environ Microbiol
PubMed ID:16000754
'Clostridium cellulovorans, an anaerobic bacterium, degrades native substrates efficiently by producing an extracellular enzyme complex called the cellulosome. All cellulosomal enzyme subunits contain dockerin domains that can bind to hydrophobic domains termed cohesins which are repeated nine times in CbpA, the nonenzymatic scaffolding protein of C. cellulovorans cellulosomes. In this ... More
Factor B and the mitochondrial ATP synthase complex.
Authors: Belogrudov Grigory I; Hatefi Youssef;
Journal:J Biol Chem
PubMed ID:11744738
Factor B is a subunit of the mammalian ATP synthase complex, whose existence has been controversial. This paper describes the molecular and functional properties of a recombinant human factor B, which when added to bovine submitochondrial particles depleted of their factor B restores the energy coupling activity of the ATP ... More