Zero Blunt™ TOPO™ PCR Cloning Kit for Sequencing, with One Shot™ Mach1™ T1 Phage-Resistant Chemically Competent E. coli
Zero Blunt&trade; TOPO&trade; PCR Cloning Kit for Sequencing, with One Shot&trade; Mach1&trade; T1 Phage-Resistant Chemically Competent <i>E. coli</i>
Invitrogen™

Zero Blunt™ TOPO™ PCR Cloning Kit for Sequencing, with One Shot™ Mach1™ T1 Phage-Resistant Chemically Competent E. coli

The Zero Blunt™ TOPO™ PCR Cloning Kits for Sequencing provide a highly efficient, 5 minute, one-step cloning strategy ('TOPO™ Cloning')Read more
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Catalog number K283520
Price (USD)
804.00
Each
Add to cart
Price (USD)
804.00
Each
Add to cart
The Zero Blunt™ TOPO™ PCR Cloning Kits for Sequencing provide a highly efficient, 5 minute, one-step cloning strategy ('TOPO™ Cloning') for the direct insertion of proofreading-polymerase–amplified blunt-end PCR products into a plasmid vector for sequencing. Each kit uses the pCR™4Blunt-TOPO™ vector with specially designed sequencing primer sites that return more insert sequence and less vector sequence from each reaction. These kits include everything necessary to clone and select recombinant vectors containing your PCR fragment of choice.

Get More Sequence—Allows for more insert sequence and less vector sequence when using standard sequencing primers

Fast and Easy—Go from PCR-to-clones in just 3 steps and in as little as 5 minutes hands-on time
Efficient—Achieve up to 95% clones with correct insert
Proven—Reliable performance for over a decade with over 4000 citations

Zero Blunt™ TOPO™ Cloning Kits for Sequencing Kit Overview
VECTOR: pCR™4Blunt-TOPO™ Vector—Optimized cloning vector for improved sequencing results
CLONING METHOD: TOPO™ Cloning —Topoisomerase I based 5 minute ligation of proofreading-polymerase-amplified PCR products with blunt ends to the vector
COMPETENT CELLS: Various Options —Choose from kits with either general, high-efficiency, bacteriophage T1-resistant, or fast-growing competent cells

pCR™4Blunt-TOPO™ VectorOptimized for Sequencing
We have removed much of the multiple cloning site from the pCR™4Blunt-TOPO™ vector to shorten the distance between sequencing primer sites and the insert site to as little as 33 bp. This means sequencing reactions give less vector sequence and more insert sequence. The pCR™4Blunt TOPO™ vector has sites for 4 common sequencing primers: M13 forward, M13 reverse, T7, and T3. The kits include an aliquot of each.

pCR™4Blunt-TOPO™ Clone Selection and Manipulation
The pCR™4Blunt-TOPO™ vector contains both ampicillin and kanamycin resistance markers and a LacZα-ccdB gene fusion for positive selection. The vector’s minimized multiple cloning site still includes flanking EcoRI sites for simplified excision of cloned PCR products and a unique Sse8387I site for generation of nested deletions prior to sequencing. T7 and T3 promoters are also present for in vitro transcription.

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 the provided E. coli competent cells.

Efficient Cloning
With up to 95% of clones carrying the desired insert, you can screen fewer clones to help you save time and money. The pCR™4Blunt-TOPO™ vector used in this kit comes with no overhangs for efficient ligation of PCR products created by proofreading, thermostable polymerases that leave blunt-ended PCR products.

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 Kits for Sequencing Kit Options
The Zero Blunt™ TOPO™ PCR Cloning Kit for Sequencing can be purchased with a variety of competent cells that deliver different advantages depending on what your needs are:

• General cloning: TOP10 (Cat. No. K2875-J10, K2875-20, K2875-40)
• High efficiency cloning: TOP10 Electrocomp™ Cells (Cat. No. K2880-20, K2880-40)
• General cloning, bacteriophage T1 resistance: DH5α-T1R (Cat. No. K2895-20)
• Fast growth: Mach1™-T1R Chemically Competent E. Coli (Cat. No. K2835-20)

TOPO™ products are For Research Use Only. Not intended for any animal or human therapeutic of diagnostic use.

Related Links
Custom Vector Construction and Cloning Services
Plasmid DNA Purification Kit Selection Guide
PCR Reagents, Instruments, and Supplies
For Research Use Only. Not for use in diagnostic procedures.
Specifications
Bacterial or Yeast StrainMach1™
Cell TypeChemically Competent
Cloning MethodBlunt TOPO™
FormatKit
For Use With (Application)Chromatin Biology
Product LineOne Shot™
Product TypePCR Cloning Kit
PromoterT7, T3
Quantity25 Reactions
VectorBlunt DNA Cloning Vectors
Unit SizeEach
Contents & Storage
Box 1:
• Topoisomerase I-activated pCR™4Blunt-TOPO™ vector
• Salt solution
• dNTPs
• Control template
• T3, T7, M13 forward, and M13 reverse primers
• Control PCR primers
• Sterile water

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

Box 2:
• One Shot™ Chemically Competent or Electrocomp™ E. coli
• S.O.C. medium
• Supercoiled pUC19 control plasmid

Store at -68 to -85°C.

Frequently asked questions (FAQs)

What is the best molar ratio of PCR product:vector to use for TOPO TA cloning? Is there an equation to calculate the quantity to use?

We suggest starting with a molar ratio of 1:1 (insert:vector), with a range of 0.5:1 to 2:1. The quantity used in a TOPO cloning reaction is typically 5-10 ng of a 2 kb PCR product.

Equation:

length of insert (bp)/length of vector (bp) x ng of vector = ng of insert needed for 1:1 (insert:vector ratio)

What is the best ratio of insert:vector to use for cloning? Is there an equation to calculate this?

The optimal ratio is 1:1 insert to vector. Optimization can be done using a ratio of 0.5-2 molecules of insert for every molecule of the vector.

Equation:

length of insert (bp)/length of vector (bp) x ng of vector = ng of insert needed for 1:1 insert:vector ratio

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.

I'm able to get a lot of colonies, however, none contain my insert of interest. What should I do?

You may be cloning in an artifact. TA and TOPO Cloning are very efficient for small fragments (< 100 bp) present in certain PCR reactions. Gel-purify your PCR product using either a silica-based DNA purification system or electroelution. Be sure that all solutions are free of nucleases (avoid communal ethidium bromide baths, for example.)