Stellar chemically competent cells for cloning

Our Stellar Competent Cells can be used in a wide variety of applications—from preparation of cDNA and genomic libraries to construction of longer-length genomic libraries, subcloning, and even methylated DNA cloning. This E. coli HST08 strain provides high transformation efficiency and since these cells lack the gene cluster for cutting foreign methylated DNA (mrr-hsdRMS-mcrBC and mcrA), they are very useful for cloning methylated DNA. The cells can also be used for blue/white screening (i.e., alpha-complementation) when transformed with vectors containing the lacZ alpha gene.

Our Stellar Competent Cells can be used in a wide variety of applications-from preparation of cDNA and genomic libraries to construction of longer-length genomic libraries, subcloning, and even methylated DNA cloning. This E. coli HST08 strain provides high transformation efficiency and since these cells lack the gene cluster for cutting foreign methylated DNA (mrr-hsdRMS-mcrBC and mcrA), they are very useful for cloning methylated DNA. The cells can also be used for blue/white screening (i.e., alpha-complementation) when transformed with vectors containing the lacZ alpha gene.

Our Stellar Competent Cells (dam−/dcm−) are generated from an E. coli HST04 strain that lacks the genetic factors (dam and dcm) necessary for the methylation of DNA. Plasmids prepared using this product can be cut by restriction enzymes which are normally blocked by dam or dcm methylation. A dam/recA double mutation is lethal, so the parent strain is recA+. Therefore, it follows that transformation of extracellular DNA with repeat sequences can result in recombination by recA. This product is not a suitable cloning host, so for transformation, it is highly recommended to use this product for constructing plasmids as mentioned above. Stellar Competent Cells are ideal for use with our In-Fusion Snap Assembly products.

More Less

Cat. #	Product	Size	Price
636763	Stellar™ Competent Cells	20 Transformations	USD $233.00
Stellar Competent Cells are an E. coli HST08 strain that provides high transformation efficiency. These cells can be used in a wide variety of applications—from preparation of cDNA and genomic libraries, to construction of longer-length genomic libraries, to subcloning, and even methylated DNA cloning. Stellar Competent Cells lack the gene cluster for cutting foreign methylated DNA (mrr-hsdRMS-mcrBC and mcrA), and are therefore useful for cloning methylated DNA. The cells can also be used for blue/white screening (i.e., α-complementation) when transformed with vectors containing the lacZα gene. A pUC19 vector is provided as well as SOC Medium. Stellar Competent Cells are recommended for use with Clontech's In-Fusion PCR Cloning Kits. Notice to purchaser Our products are to be used for Research Use Only. They may not be used for any other purpose, including, but not limited to, use in humans, therapeutic or diagnostic use, or commercial use of any kind. Our products may not be transferred to third parties, resold, modified for resale, or used to manufacture commercial products or to provide a service to third parties without our prior written approval. Documents Components Image Data Back 636763: Stellar Competent Cells Back Stellar Competent Cells provided transformation efficiencies equivalent to or better than those obtained using DH5α or DH10B competent cells The high efficiency of Stellar Competent Cells was especially noticeable in the transformation of 10 kb and 20 kb plasmids. Using DNA plasmids of 2 kb (100 pg), 10 kb (1 ng), and 20 kb (1 ng), each strain of competent cells was transformed and plated on ampicillin-containing LB agar plates. Transformation efficiencies were determined based on the colony counts obtained. Back Stellar Competent Cells provided the highest transformation efficiencies for all the ligation reaction mixtures tested. The difference in transformation efficiencies of the competent cells was particularly prominent when cloning 20 kb fragments. Ligation reactions were set up with either 100 ng of a 2 kb, Hind III-cut DNA fragment + 50 ng of Hind III/BAP-cut pUC118 vector, or 75 ng of a 20 kb, Hind III-cut DNA fragment + 25 ng of Hind III/BAP-cut pUC118 vector. All reactions were performed at 16℃ for 6 hours using the Takara DNA Ligation Kit (Cat# 6023 or 6024). Each strain of competent cells was transformed using portions of these reaction mixtures and plated on ampicillin-containing LB agar (+ X-gal). Transformation efficiencies were determined based on the white colony counts obtained. Back Stellar Competent Cell colonies showed a faster growth rate than DH10B colonies Stellar colonies transformed with larger plasmid clearly showed a faster growth rate. DNA plasmids of 2 kb (Panel A) and 10 kb (Panel B) were each used to transform Stellar and DH10B competent cells with similar genetic characteristics, including methylation requiring restriction. This experiment used the same method as in Figure 1. Photographs of colonies on agar were taken after 15 hours of incubation.
636766	Stellar™ Competent Cells	100 Transformations	USD $808.00
Stellar Competent Cells are an E. coli HST08 strain that provides high transformation efficiency. These cells can be used in a wide variety of applications-from preparation of cDNA and genomic libraries, to construction of longer-length genomic libraries, to subcloning, and even methylated DNA cloning. Stellar Competent Cells lack the gene cluster for cutting foreign methylated DNA (mrr-hsdRMS-mcrBC and mcrA), and are therefore useful for cloning methylated DNA. The cells can also be used for blue/white screening (i.e., α-complementation) when transformed with vectors containing the lacZα gene. This package includes 50 tubes of competent cells (100 μl/tube), SOC Medium and a pUC19 vector. Notice to purchaser Our products are to be used for Research Use Only. They may not be used for any other purpose, including, but not limited to, use in humans, therapeutic or diagnostic use, or commercial use of any kind. Our products may not be transferred to third parties, resold, modified for resale, or used to manufacture commercial products or to provide a service to third parties without our prior written approval. Documents Components Image Data Back 636766: Stellar Competent Cells Back Stellar Competent Cells provided transformation efficiencies equivalent to or better than those obtained using DH5α or DH10B competent cells The high efficiency of Stellar Competent Cells was especially noticeable in the transformation of 10 kb and 20 kb plasmids. Using DNA plasmids of 2 kb (100 pg), 10 kb (1 ng), and 20 kb (1 ng), each strain of competent cells was transformed and plated on ampicillin-containing LB agar plates. Transformation efficiencies were determined based on the colony counts obtained. Back Stellar Competent Cells provided the highest transformation efficiencies for all the ligation reaction mixtures tested. The difference in transformation efficiencies of the competent cells was particularly prominent when cloning 20 kb fragments. Ligation reactions were set up with either 100 ng of a 2 kb, Hind III-cut DNA fragment + 50 ng of Hind III/BAP-cut pUC118 vector, or 75 ng of a 20 kb, Hind III-cut DNA fragment + 25 ng of Hind III/BAP-cut pUC118 vector. All reactions were performed at 16℃ for 6 hours using the Takara DNA Ligation Kit (Cat# 6023 or 6024). Each strain of competent cells was transformed using portions of these reaction mixtures and plated on ampicillin-containing LB agar (+ X-gal). Transformation efficiencies were determined based on the white colony counts obtained. Back Stellar Competent Cell colonies showed a faster growth rate than DH10B colonies Stellar colonies transformed with larger plasmid clearly showed a faster growth rate. DNA plasmids of 2 kb (Panel A) and 10 kb (Panel B) were each used to transform Stellar and DH10B competent cells with similar genetic characteristics, including methylation requiring restriction. This experiment used the same method as in Figure 1. Photographs of colonies on agar were taken after 15 hours of incubation.
636767	Stellar™ Competent Cells (96-well plate)	96 x 20 uL	USD $558.00
Stellar Competent Cells arranged in a 96-well plate for high-throughput transformation. Stellar Cells are an E. coli HST08 strain that provides high transformation efficiency. These cells can be used in a wide variety of applications: from preparation of cDNA and genomic libraries, to construction of longer-length genomic libraries, to subcloning, and even methylated DNA cloning. Stellar Competent Cells lack the gene cluster for cutting foreign methylated DNA (mrr-hsdRMS-mcrBC and mcrA), and are therefore useful for cloning methylated DNA. The cells can also be used for blue/white screening (i.e., α-complementation) when transformed with vectors containing the lacZα gene. A pUC19 vector, SOC Medium, 8-Cap Strips, and a Plate Lid are included. These competent cells are recommended for use with Takara Bio's In-Fusion PCR Cloning Kits. Notice to purchaser Our products are to be used for Research Use Only. They may not be used for any other purpose, including, but not limited to, use in humans, therapeutic or diagnostic use, or commercial use of any kind. Our products may not be transferred to third parties, resold, modified for resale, or used to manufacture commercial products or to provide a service to third parties without our prior written approval. Documents Components Image Data Back Stellar Competent Cells provided transformation efficiencies equivalent to or better than those obtained using DH5α or DH10B competent cells The high efficiency of Stellar Competent Cells was especially noticeable in the transformation of 10 kb and 20 kb plasmids. Using DNA plasmids of 2 kb (100 pg), 10 kb (1 ng), and 20 kb (1 ng), each strain of competent cells was transformed and plated on ampicillin-containing LB agar plates. Transformation efficiencies were determined based on the colony counts obtained. Back Stellar Competent Cells provided the highest transformation efficiencies for all the ligation reaction mixtures tested. The difference in transformation efficiencies of the competent cells was particularly prominent when cloning 20 kb fragments. Ligation reactions were set up with either 100 ng of a 2 kb, Hind III-cut DNA fragment + 50 ng of Hind III/BAP-cut pUC118 vector, or 75 ng of a 20 kb, Hind III-cut DNA fragment + 25 ng of Hind III/BAP-cut pUC118 vector. All reactions were performed at 16℃ for 6 hours using the Takara DNA Ligation Kit (Cat# 6023 or 6024). Each strain of competent cells was transformed using portions of these reaction mixtures and plated on ampicillin-containing LB agar (+ X-gal). Transformation efficiencies were determined based on the white colony counts obtained. Back Stellar Competent Cell colonies showed a faster growth rate than DH10B colonies Stellar colonies transformed with larger plasmid clearly showed a faster growth rate. DNA plasmids of 2 kb (Panel A) and 10 kb (Panel B) were each used to transform Stellar and DH10B competent cells with similar genetic characteristics, including methylation requiring restriction. This experiment used the same method as in Figure 1. Photographs of colonies on agar were taken after 15 hours of incubation. Back Stellar Competent Cells (96-well plate)Catalog No.636767
636764	Stellar™ Competent Cells (dam-/dcm-)	10 Transformations	USD $233.00
Stellar Competent Cells (dam-/dcm-) are an E. coli HST04 strain that lacks the genetic factors (dam and dcm) necessary for the methylation of DNA. Plasmids prepared using this product can be cut by restriction enzymes which are normally blocked by dam or dcm methylation. A dam/recA double mutation is lethal, so the parent strain is recA+. Therefore, it follows that transformation of extracellular DNA with repeat sequences can result in recombination by recA. This product is not a suitable cloning host. For transformation, it is highly recommended to use this product for constructing plasmids as mentioned above. A pUC19 vector is provided as well as SOC Medium. Notice to purchaser Our products are to be used for Research Use Only. They may not be used for any other purpose, including, but not limited to, use in humans, therapeutic or diagnostic use, or commercial use of any kind. Our products may not be transferred to third parties, resold, modified for resale, or used to manufacture commercial products or to provide a service to third parties without our prior written approval. Documents Components Image Data Back 636764: Stellar Competent Cells (dam-/dcm-) Back Stellar Competent Cells provided transformation efficiencies equivalent to or better than those obtained using DH5α or DH10B competent cells The high efficiency of Stellar Competent Cells was especially noticeable in the transformation of 10 kb and 20 kb plasmids. Using DNA plasmids of 2 kb (100 pg), 10 kb (1 ng), and 20 kb (1 ng), each strain of competent cells was transformed and plated on ampicillin-containing LB agar plates. Transformation efficiencies were determined based on the colony counts obtained. Back Stellar Competent Cells provided the highest transformation efficiencies for all the ligation reaction mixtures tested. The difference in transformation efficiencies of the competent cells was particularly prominent when cloning 20 kb fragments. Ligation reactions were set up with either 100 ng of a 2 kb, Hind III-cut DNA fragment + 50 ng of Hind III/BAP-cut pUC118 vector, or 75 ng of a 20 kb, Hind III-cut DNA fragment + 25 ng of Hind III/BAP-cut pUC118 vector. All reactions were performed at 16℃ for 6 hours using the Takara DNA Ligation Kit (Cat# 6023 or 6024). Each strain of competent cells was transformed using portions of these reaction mixtures and plated on ampicillin-containing LB agar (+ X-gal). Transformation efficiencies were determined based on the white colony counts obtained. Back Stellar Competent Cell colonies showed a faster growth rate than DH10B colonies Stellar colonies transformed with larger plasmid clearly showed a faster growth rate. DNA plasmids of 2 kb (Panel A) and 10 kb (Panel B) were each used to transform Stellar and DH10B competent cells with similar genetic characteristics, including methylation requiring restriction. This experiment used the same method as in Figure 1. Photographs of colonies on agar were taken after 15 hours of incubation.

Overview

Stellar Competent Cells

Transformation efficiency: >5 × 10⁸ cfu/µg (may improve with reduced heat-shock time)
Genotype: F-, endA1, supE44, thi-1, recA1, relA1, gyrA96, phoA, Φ80d lacZΔ M15, Δ(lacZYA-argF) U169, Δ(mrr-hsdRMS-mcrBC), ΔmcrA, λ-

Stellar Competent Cells (dam⁻/dcm⁻)

Transformation efficiency: >1 × 10⁶ cfu/µg (may improve with reduced heat-shock time)
Genotype: F-, ara,Δ(lac-proAB) [Φ80d lacZΔM15], rpsL(str), thi, Δ(mrr-hsdRMS-mcrBC), ΔmcrA, dam, dcm

More Information

Applications

Cloning, subcloning
Methylated DNA cloning
cDNA and genomic library construction
Longer-length cDNA library construction

Additional product information

Please see the product's Certificate of Analysis for information about storage conditions, product components, and technical specifications. Please see the Kit Components List to determine kit components. Certificates of Analysis and Kit Components Lists are located under the Documents tab.

Takara Bio USA, Inc.
United States/Canada: +1.800.662.2566 • Asia Pacific: +1.650.919.7300 • Europe: +33.(0)1.3904.6880 • Japan: +81.(0)77.565.6999
FOR RESEARCH USE ONLY. NOT FOR USE IN DIAGNOSTIC PROCEDURES. © 2023 Takara Bio Inc. All Rights Reserved. All trademarks are the property of Takara Bio Inc. or its affiliate(s) in the U.S. and/or other countries or their respective owners. Certain trademarks may not be registered in all jurisdictions. Additional product, intellectual property, and restricted use information is available at takarabio.com.

Stellar chemically competent cells for cloning

Notice to purchaser

636763: Stellar Competent Cells

Stellar Competent Cells provided transformation efficiencies equivalent to or better than those obtained using DH5α or DH10B competent cells

Stellar Competent Cells provided the highest transformation efficiencies for all the ligation reaction mixtures tested.

Stellar Competent Cell colonies showed a faster growth rate than DH10B colonies

Notice to purchaser

636766: Stellar Competent Cells

Stellar Competent Cells provided transformation efficiencies equivalent to or better than those obtained using DH5α or DH10B competent cells

Stellar Competent Cells provided the highest transformation efficiencies for all the ligation reaction mixtures tested.

Stellar Competent Cell colonies showed a faster growth rate than DH10B colonies

Notice to purchaser

Stellar Competent Cells provided transformation efficiencies equivalent to or better than those obtained using DH5α or DH10B competent cells

Stellar Competent Cells provided the highest transformation efficiencies for all the ligation reaction mixtures tested.

Stellar Competent Cell colonies showed a faster growth rate than DH10B colonies

Stellar Competent Cells (96-well plate)Catalog No.636767

Notice to purchaser

636764: Stellar Competent Cells (dam-/dcm-)

Stellar Competent Cells provided transformation efficiencies equivalent to or better than those obtained using DH5α or DH10B competent cells

Stellar Competent Cells provided the highest transformation efficiencies for all the ligation reaction mixtures tested.

Stellar Competent Cell colonies showed a faster growth rate than DH10B colonies

Overview

Stellar Competent Cells

Stellar Competent Cells (dam−/dcm−)

More Information

Applications

Additional product information

Stellar Competent Cells (dam⁻/dcm⁻)