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Competent Cells Support
Explore our “Getting Started” and “Troubleshooting” sections for solutions to top inquiries and common problems. Browse through our "Guides and Tools" section to access a comprehensive portfolio of product-related support resources.
Getting Started
- I need a competent cell strain that is ccdB resistant. The Library Efficiency® DB3.1 cells you offer have been discontinued, as well as the One Shot® ccdB Survival™ T1R chemically competent cells. What do you recommend?
- I’m trying to decide between the TOP10, DH5α™, and Mach1™ strains you have for my TOPO® TA Cloning® reactions. Can you explain the significant differences between these strains?
- You offer Subcloning Efficiency™, Library Efficiency®, and MAX Efficiency® competent cells. How do these differ?
- What are some tips you can give me to obtain the highest transformation efficiency?
- What restriction enzymes are sensitive to dam and dcm methylation?
Troubleshooting
- My competent cells were stored at –20 degrees C instead of –80 degrees C. Can I still use them?
- I’m getting no colonies at all on my plates.
- I’m trying to clone a gene that has multiple repeated sequences into my pCR®2.1-TOPO® vector, followed by transformation into TOP10 cells. My clones contain random rearrangements and deletions.
- I’m trying to transform a large plasmid, 40 kb in size. What strain should I use?
- I’m only getting white colonies, but none of the clones have an insert.
Guides and Tools
- Overview: Common Cloning Applications and Strategies
- Overview: Bacterial Transformation Workflow
- Brochure: Competent Cells
- Selection Table: Competent Cell Selection Guide
- Statement: Statement of Non-pathogenicity
- Table: Recommended Antibiotic Concentrations
- Search our database for Product Documents: Manuals, Vector Maps, Citations and References
- Search our database for Quality and Safety Documents: MSDSs, COAs
- Restriction Enzyme Finder
- Vector Selection Tool
- Vector NTI: a bioinformatics software package
Custom Services
Cloning Services
From custom vector design to high-throughput protein expression, we have a solution to meet your needs
Plasmid Services
GeneArt® Plasmid Services include flexible offerings covering construction of plasmid vectors customized for your needs, and subcloning of your sequence into any vector, including the Gateway® vector system. Concentrate on your research goals and leave your plasmid construction and subcloning work to us.
Protein Expression Services
Have us utilize our extensive suite of expression vectors and host systems to deliver the necessary protein yield for your application. We offer protein expression and production services in baculovirus and mammalian host systems, as well as protein purification and analysis services.
For Research Use Only. Not for use in diagnostic procedures.