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

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

The TOPO™ TA Cloning™ Kits for Sequencing provide a highly efficient, 5-minute, one-step cloning strategy ('TOPO™ Cloning') for the directRead more
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Catalog NumberQuantity
K4575J1010 Reactions
K45750125 Reactions
K45754050 Reactions
Catalog number K4575J10
Price (USD)
433.65
Online Exclusive
448.00
Save 14.35 (3%)
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Quantity:
10 Reactions
Price (USD)
433.65
Online Exclusive
448.00
Save 14.35 (3%)
Each
Add to cart
The TOPO™ TA Cloning™ Kits for Sequencing provide a highly efficient, 5-minute, one-step cloning strategy ('TOPO™ Cloning') for the direct insertion of Taq polymerase–amplified PCR products into a plasmid vector for sequencing. Each kit uses the pCR™4-TOPO™ TA vector with specially designed sequencing primer sites that return more insert sequence and less vector sequence from each reaction, and are available with a variety of competent cells, or no competent cells, depending on your needs and budget. These kits include everything necessary to clone and select recombinant vectors containing your PCR fragment of choice. Features of TOPO™ TA Cloning™ Kits for Sequencing:

Get more sequence—allows for more insert sequence and less vector seuquence 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—obtain up to 95% clones with correct insert
Proven—reliable performance for over a decade with over 4,000 citations

TOPO™ TA Cloning™ Kits for Sequencing—overview

Vector: pCR™4-TOPO™ TA vector—optimized cloning vector for improved sequencing results

Cloning method: TOPO™ TA Cloning™—Topoisomerase I–based, 5-minute ligation of PCR products with 3´A overhangs (Taq-amplified) to the vector

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

pCR™4-TOPO™ TA vectoroptimized for sequencing
We have removed much of the multiple cloning site from the pCR™4-TOPO™ TA 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™4-TOPO™ TA vector has sites for 4 common sequencing primers: M13 forward, M13 reverse, T7, and T3. The kits include an aliquot of each.

pCR™4-TOPO™ TA clone selection and manipulation
The pCR™4-TOPO™ TA vector contains both ampicillin and kanamycin resistance markers and a LacZα-ccdB gene fusion for positive selection and blue/white screening. 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 with the providedE. coli competent cells.

Efficient cloning
With up to 95% of clones carrying the desired insert, you can screen less clones and save time and money. The pCR™4-TOPO™ TA vector used in this kit comes with 3´T overhangs for efficient ligation of Taq-amplified PCR products, which contain 3´A overhangs.

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.

TOPO™ TA Cloning™ Kits for Sequencing—kit options
The TOPO™ TA Cloning™ Kit for Sequencing can be purchased with a variety of competent cells that deliver different advantages depending upon your needs:

• General cloning: TOP10 (Cat. No. K4575-J10, K4575-01, K4575-40)
• High-efficiency cloning: TOP10 Electrocomp™ Cells (Cat. No. K4580-01, K4580-40)
• General cloning, bacteriophage T1 resistance: DH5α-T1R (Cat. No. K4595-01, K4595-40)
• Fast growth: Mach1™-T1R Chemically Competent E. Coli (Cat. No. K4530-20)
• Provide your own: for flexibility and to save money (Cat. No. 450030)

We also offer a version of the kit that includes a PureLink™ Quick Plasmid Miniprep Kit (Cat. No. K4575-02) for use in isolation of clean, sequencing-ready, recombinant plasmid.

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 MethodTOPO™-TA
For Use With (Application)Chromatin Biology
Product LineOne Shot
Product TypeCloning Kit
Quantity10 Reactions
VectorTOPO-TA Cloning Vectors
FormatKit
PromoterT7, T3
Unit SizeEach
Contents & Storage
Each TOPO™ Cloning Kit for Sequencing contains pCR™4-TOPO™ or pCR™4Blunt-TOPO™ Vector, Salt Solution, dNTPs, Control Template and Primers, T3, T7, M13 (-20) Forward and M13 Reverse Primers, One Shot™ Chemically Competent or Electrocomp™ E. coli, S.O.C. Medium, and pUC19 Control Plasmid. Store the One Shot™ E. coli at -80°C. Store all other components at -20°C. All reagents are guaranteed stable for 6 months when properly stored.

Frequently asked questions (FAQs)

Can I store my competent E. coli in liquid nitrogen?

We do not recommend storing competent E. coli strains in liquid nitrogen as the extreme temperature can be harmful to the cells. Also, the plastic storage vials are not intended to withstand the extreme temperature and may crack or break.

How should I store my competent E. coli?

We recommend storing our competent E. coli strains at -80°C. Storage at warmer temperatures, even for a brief period of time, will significantly decrease transformation efficiency.

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

Does Platinum Taq DNA Polymerase High Fidelity enzyme mix leave 3' A-overhangs on the PCR product for subsequent cloning into a TOPO TA or original TA vector?

Yes, the enzyme mix leaves 3' A-overhangs on a portion of the PCR products. However, the cloning efficiency is greatly decreased compared to that obtained with Taq polymerase alone. It is recommended to add 3' A-overhangs to the product for TA cloning.

Citations & References (8)

Citations & References
Abstract
Molecular cloning and characterization of Foxp3 in Atlantic salmon (Salmo salar).
Authors:Zhang Z, Chi H, Niu C, Bøgwald J, Dalmo RA,
Journal:Fish Shellfish Immunol
PubMed ID:21276855
'Foxp3 is a T cell-specific transcription factor and plays a key role in the development of Treg cells and in the immune regulatory process during inflammation. Here we report cloning and characterization of the full-length cDNA of Atlantic salmon Foxp3, which possesses a Forkhead domain, a zinc finger domain and ... More
Diversity and functionality of arbuscular mycorrhizal fungi in three plant communities in semiarid Grasslands National Park, Canada.
Authors:Yang C, Hamel C, Schellenberg MP, Perez JC, Berbara RL
Journal:Microb Ecol
PubMed ID:20082070
'Septate endophytes proliferating in the roots of grasslands'' plants shed doubts on the importance of arbuscular mycorrhizal (AM) symbioses in dry soils. The functionality and diversity of the AM symbioses formed in four replicates of three adjacent plant communities (agricultural, native, and restored) in Grasslands National Park, Canada were assessed ... More
Detection of cytosine methylation in RNA using bisulfite sequencing.
Authors:Pollex T, Hanna K, Schaefer M
Journal:Cold Spring Harb Protoc
PubMed ID:20889702
'Post-transcriptional RNA modifications are a characteristic feature of noncoding RNAs and have been described for ribosomal RNAs (rRNAs), transfer RNAs (tRNAs), and various other small RNAs. However, the biological function of most of these modifications remains uncharacterized. Cytosine-5 methylation (5mC) has been detected in abundant and long-lived RNA molecules such ... More
Unique DNA methylome profiles in CpG island methylator phenotype colon cancers.
Authors:Xu Y, Hu B, Choi AJ, Gopalan B, Lee BH, Kalady MF, Church JM, Ting AH
Journal:Genome Res
PubMed ID:21990380
'A subset of colorectal cancers was postulated to have the CpG island methylator phenotype (CIMP), a higher propensity for CpG island DNA methylation. The validity of CIMP, its molecular basis, and its prognostic value remain highly controversial. Using MBD-isolated genome sequencing, we mapped and compared genome-wide DNA methylation profiles of ... More
Evolution of major milk proteins in Mus musculus and Mus spretus mouse species: a genoproteomic analysis.
Authors:Boumahrou N, Bevilacqua C, Beauvallet C, Miranda G, Andrei S, Rebours E, Panthier JJ, Bellier S, Martin P
Journal:BMC Genomics
PubMed ID:21276224
'Due to their high level of genotypic and phenotypic variability, Mus spretus strains were introduced in laboratories to investigate the genetic determinism of complex phenotypes including quantitative trait loci. Mus spretus diverged from Mus musculus around 2.5 million years ago and exhibits on average a single nucleotide polymorphism (SNP) in ... More