Zero Blunt™ TOPO™ PCR Cloning Kit for Sequencing, with One Shot™ TOP10 Chemically Competent E. coli
Zero Blunt&trade; TOPO&trade; PCR Cloning Kit for Sequencing, with One Shot&trade; TOP10 Chemically Competent <i>E. coli</i>
Invitrogen™

Zero Blunt™ TOPO™ PCR Cloning Kit for Sequencing, with One Shot™ TOP10 Chemically Competent E. coli

The Zero Blunt™ TOPO™ PCR Cloning Kit for Sequencing provides a highly efficient, 5-minute, one-step cloning strategy for the directRead more
Have Questions?
Change viewbuttonViewtableView
Catalog NumberQuantity
K28752025 Reactions
K2875J1010 Reactions
K28754050 Reactions
Catalog number K287520
Price (MXN)
-
Quantity:
25 Reactions
The Zero Blunt™ TOPO™ PCR Cloning Kit for Sequencing provides a highly efficient, 5-minute, one-step cloning strategy for the direct insertion of proofreading-polymerase–amplified, blunt-ended PCR products into a plasmid vector for sequencing. Each kit uses the pCR™4Blunt-TOPO™ vector (see figure) 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.

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, which saves you 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 Kit for Sequencing—kit formats
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 cells (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)

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 StrainTOP10
Cell TypeChemically Competent
Cloning MethodBlunt TOPO™
For Use With (Application)Chromatin Biology
Product LineOne Shot
Product TypePCR Cloning Kit
PromoterT7, T3
Quantity25 Reactions
VectorBlunt DNA Cloning Vectors
FormatKit
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.)

Citations & References (7)

Citations & References
Abstract
Expression of human NAA11 (ARD1B) gene is tissue-specific and is regulated by DNA methylation.
Authors:Pang AL, Clark J, Chan WY, Rennert OM
Journal:Epigenetics
PubMed ID:22048246
'NAA10 gene encodes the catalytic subunit of N(alpha)-acetyltransferase NatA that catalyzes the acetylation of the N-termini of many eukaryotic proteins. A homologous gene called NAA11 is also present in mammalian cells. hNaa10p and hNaa11p are reported to be co-expressed in human cell cultures. In mouse tissues, however, Naa11 transcripts can ... More
The plant biotin synthase reaction. Identification and characterization of essential mitochondrial accessory protein components.
Authors:Picciocchi A, Douce R, Alban C,
Journal:J Biol Chem
PubMed ID:12714594
In plants, the last step of the biotin biosynthetic pathway is localized in mitochondria. This chemically complex reaction is catalyzed by the biotin synthase protein, encoded by the bio2 gene in Arabidopsis thaliana. Unidentified mitochondrial proteins in addition to the bio2 gene product are obligatory for the reaction to occur. ... More
Construction and testing of engineered zinc-finger proteins for sequence-specific modification of mtDNA.
Authors:Minczuk M, Kolasinska-Zwierz P, Murphy MP, Papworth MA
Journal:Nat Protoc
PubMed ID:20134433
Engineered zinc-finger proteins (ZFPs) are hybrid proteins developed to direct various effector domains (EDs) of choice to predetermined DNA sequences. They are used to alter gene expression and to modify DNA in a sequence-specific manner in vivo and in vitro. Until now, ZFPs have mostly been used to target DNA ... More
Quantification of adenosine-to-inosine editing of microRNAs using a conventional method.
Authors:Kawahara Y
Journal:Nat Protoc
PubMed ID:22743833
In this protocol, I describe a method for measuring the frequency of adenosine-to-inosine RNA editing of primary, precursor and mature forms of specific microRNAs (miRNAs) derived from the same source. The procedure involves reverse transcription (RT)-PCR amplification of regions containing the editing sites followed by subcloning of the PCR products ... More
Assembling the glycopeptide antibiotic scaffold: The biosynthesis of A47934 from Streptomyces toyocaensis NRRL15009.
Authors: Pootoolal Jeff; Thomas Michael G; Marshall C Gary; Neu John M; Hubbard Brian K; Walsh Christopher T; Wright Gerard D;
Journal:Proc Natl Acad Sci U S A
PubMed ID:12060705
The glycopeptide antibiotics vancomycin and teicoplanin are vital components of modern anti-infective chemotherapy exhibiting outstanding activity against Gram-positive pathogens including members of the genera Streptococcus, Staphylococcus, and Enterococcus. These antibiotics also provide fascinating examples of the chemical and associated biosynthetic complexity exploitable in the synthesis of natural products by actinomycetes ... More