Zero Blunt™ TOPO™ PCR Cloning Kit, without competent cells
Zero Blunt™ TOPO™ PCR Cloning Kit, without competent cells
Invitrogen™

Zero Blunt™ TOPO™ PCR Cloning Kit, without competent cells

Zero Blunt™ TOPO™ PCR Cloning Kit provides a highly efficient, 5-minute, one-step cloning strategy ("TOPO™ Cloning") for the direct insertionRead more
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Catalog NumberQuantity
45024525 Reactions
45124510 Reactions
Catalog number 450245
Price (USD)
335.40
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Online exclusive
Ends: 17-Jul-2025
516.00
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Quantity:
25 Reactions
Price (USD)
335.40
Special offer
Online exclusive
Ends: 17-Jul-2025
516.00
Save 180.60 (35%)
Each
Add to cart
Zero Blunt™ TOPO™ PCR Cloning Kit provides a highly efficient, 5-minute, one-step cloning strategy ("TOPO™ Cloning") for the direct insertion of blunt-ended PCR products amplified with proofreading thermostable polymerases into a plasmid vector. Each kit has the Zero Blunt™ TOPO™ vector (see figure) containing the ccdB gene for positive selection, only permitting growth of plasmid vectors with recombinants. Zero™ Blunt™ TOPO™ kits are available with a variety of competent cells, or without competent cells, depending on your needs and budget. Features of the Zero™ Blunt™ TOPO™ PCR Cloning Kits:

Fast and easy—go from PCR to clones in just 3 steps and in as little as 5 minutes hands-on time
Efficient—obtain up to 95% clones with correct insert
Proven—reliable performance for over a decade with over 4,000 citations
Simple —no ligase, post-PCR procedures, or PCR primers containing specific sequences are required.

Zero Blunt™ TOPO™ Cloning Kits—overview

Vector: pCR™Blunt II-TOPO™ vector—contains the ccdB gene, allowing for direct selection of recombinants

Cloning method: TOPO™ cloning—Topoisomerase I–based, 5-minute ligation of blunt-ended PCR products amplified with proofreading thermostable polymerases

Competent cells: Various options—choose from kits with either general, high-efficiency, bacteriophage T1-resistant, fast-growing competent cells, or use your own.

pCR™Blunt II-TOPO™ vector—designed for proofreading polymerases
The pCR™Blunt II-TOPO™ vector is designed to clone blunt-ended PCR products generated by thermostable proofreading polymerases such as Platinum™ Pfx DNA Polymerase. The pCR™Blunt II-TOPO™ vector contains:

• EcoRI sites flanking the PCR product insertion site for easy excision of inserts
• Kanamycin and Zeocin™ resistance genes for your choice of selection in E. coli
• SP6 promoter/primer site for in vitro RNA transcription and sequencing
• M13 forward and reverse primer sites for sequencing or PCR screening

pCR™Blunt II-TOPO™ clone selection
pCR™-Blunt II-TOPO™ allows for direct selection of recombinants via disruption of the lethal E. coli gene, ccdB. The vector contains the ccdB gene fused to the C-terminus of the LacZα fragment. Ligation of a blunt-end PCR product disrupts expression of the LacZα-ccdB gene fusion, permitting growth of only positive recombinants upon transformation. Cells that contain non-recombinant vector are killed upon plating. Therefore, blue/white screening is not required.

Simplified TOPO™-based cloning
Using TOPO™ cloning technology, there is no need for PCR primers containing specific sequences, post-PCR procedures, vector preparation, or other time-intensive DNA manipulation steps. Just add your PCR reaction straight to the provided topoisomerase-charged vector, incubate 5 minutes, and transform E. coli competent cells.

Efficient cloning
With up to 95% of clones carrying the desired insert, you can screen less clones, saving you time and money. The pCR™Blunt II-TOPO™ vector used in this kit comes with lethal ccdB gene for efficient selection of blunt-ended PCR recombinants products generated bythermostable proofreading polymerases.

The standard in cloning
When it comes to cloning, TOPO™ cloning technology has been a reliable partner for thousands of scientists for over ten years. Fast, simple-to-use, and efficient, TOPO™ cloning has been applied to many different vectors for a wide array of applications.

Zero Blunt™ TOPO™ PCR Cloning™ Kit options
The Zero Blunt™ TOPO™ PCR Cloning Kit for direct insertion of blunt-ended PCR products into a plasmid vector can be purchased with a variety of competent cells that deliver different advantages depending upon your needs:

General cloning: TOP10 cells (Cat. No. K2800-20, K2800-40)
High-efficiency cloning: TOP10 Electrocomp™ Cells (Cat. No. K2860-01, K2860-40)
General cloning, bacteriophage T1 resistance: DH5α-T1R (Cat. No. K2820-20, K2820-40)
Fast growth: Mach1™-T1R Chemically Competent E. Coli (Cat. No. K2830-20)
Provide your own: for flexibility and to save money (Cat. No. 450254)

We also offer a version of the kit that includes a PureLink™ Quick Plasmid Miniprep Kit (Cat. No. K2800-02) for use in isolation of clean, sequencing-ready, recombinant plasmid.
For Research Use Only. Not for use in diagnostic procedures.
Specifications
Antibiotic Resistance BacterialKanamycin (KanR), Zeocin™ (ZeoR)
Bacterial or Yeast StrainNot Included
Cloning MethodBlunt TOPO™
Product LineTOPO™, Zero Blunt™
Product TypePCR Cloning Kit
PromoterSP6
Quantity25 Reactions
Shipping ConditionDry Ice
VectorBlunt DNA Cloning Vectors, TOPO Cloning Vectors, pCR
FormatKit
Unit SizeEach
Contents & Storage
Box 1:
• Linearized and topoisomerase I-activated pCR™Blunt II-TOPO™ vector
• Salt solution
• dNTPs
• Control template
• M13 forward and reverse primers
• Sterile water

Store at -5 to -30°C.
All reagents are stable for 6 months when properly stored.

Frequently asked questions (FAQs)

What is the difference between the pCR2.1-TOPO and pCR4-TOPO vectors?

The vector backbones for both of these vectors are very similar. The main difference is that the pCR4-TOPO vector has sequencing primer sites located as close as 33 base pairs from the PCR product insertion site. This minimizes the amount of vector DNA sequence that needs to be read before reaching the sequence of the insert, making the pCR4-TOPO vector very useful for sequencing applications.

What is the difference between the pCR2.1-TOPO and pCRII-TOPO vectors?

The vector backbones for both of these vectors are very similar. The main difference is that the pCRII-TOPO vector is a dual promoter vector, containing the SP6 and T7 promoters for in vitro transcription/sequencing, whereas the pCR2.1-TOPO vector contains only the T7 promoter for in vitro transcription/sequencing. Both vectors contain the M13 Forward and Reverse primer sites for sequencing or PCR screening.

Your TOPO cloning kits contain a control template and control primers. Can I obtain the sequence of the control template?

The sequence of the control template is proprietary.

I'm seeing a lot of vector-only colonies when I try to perform a negative control reaction using vector only (no insert) for a TOPO reaction. Is my TOPO vector re-ligating?

Using the vector only for transformation is not a recommended negative control. The process of TOPO-adaptation is not a 100% process, therefore, there will be “vector only” present in your mix, and colonies will be obtained.

I'm trying to clone in my phosphorylated PCR product into a TOPO vector, and I'm getting no colonies. However, when I clone the same product into a TA vector, everything works perfectly. Why is this?

Phosphorylated products can be TA cloned but not TOPO cloned. This is because the necessary phosphate group is contained within the topoisomerase-DNA intermediate complex of the vector. TOPO vectors have a 3' phosphate to which topoisomerase is covalently bound and a 5' phosphate. Non-TOPO linear vectors (TA and Blunt) have a 3' OH and a 5' phosphate. Phosphorylated products should be phosphatased (CIP) before TOPO cloning.

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