Champion™ Competent Cells are chemically competent cells, which were prepared by SMOBIO to make E. coli perform excellent transformation efficiency. Standard transformation protocol is recommended for large plasmids or non-ampicillin selection. Time-saving transformation protocol is recommended for simple and rapid transformation. Champion™ Competent Cells are one of the fastest and simplest ready-to-use competent cell products in the world.
Detail
General information
Champion™ Competent Cells are chemically competent cells, which were prepared by SMOBIO to make E. coli perform excellent transformation efficiency. Standard transformation protocol is recommended for large plasmids or non-ampicillin selection. Time-saving transformation protocol is recommended for simple and rapid transformation. Champion™ Competent Cells are one of the fastest and simplest ready-to-use competent cell products in the world.
Kit contents
Champion™ Competent Cells
pUC19 Control Plasmid (5 μl, 10-4 μg/μl)
Champion™ Transformation Protocol Card
Shipping condition
Throughout the shipping process, the temperature is maintained under -70°C.
Storage and expiration
Champion™ Competent Cells must be stored between -70°C to -80°C. Subsequent freeze-thaw cycles will reduce transformation efficiency. If high efficiency is required for the experiment, do not use aliquots that have gone through several freeze-thaw cycles. The efficiency of Champion™ Competent Cells lasts for 1 year with proper storage.
Escherichia coli is one of many species of bacteria living in the lower intestines of mammals, known as gut flora. When located in the large intestine, it assists with waste processing, vitamin K production, and food absorption. Discovered in 1885 by Theodor Escherich, a German pediatrician and bacteriologist, E. coli are abundant: the number of individual E. coli bacteria in the faeces that a human defecates in one day averages between 100 billion and 10 trillion. However, the bacteria are not confined to the environment, and specimens have also been located, for example, on the edge of hot springs. The E. coli strain O157:H7 is one of hundreds of strains of the bacterium that causes illness in humans.
E. coli are unable to sporulate. Thus, treatments which kill all active bacteria, such as pasteurization or simple boiling, are effective for their eradication, without requiring the more rigorous sterilization which also deactivates spores. As a result of their adaptation to mammalian intestines, E. coli grow best in vivo or at the higher temperatures characteristic of such an environment, rather than the cooler temperatures found in soil and other environments.
The enteric E. coli (EC) are divided on the basis of virulence properties into enterotoxigenic (ETEC – causative agent of diarrhea in humans, pigs, sheep, goats, cattle, dogs, and horses), enteropathogenic (EPEC – causative agent of diarrhea in humans, rabbits, dogs, cats and horses); enteroinvasive (EIEC – found only in humans), verotoxigenic (VTEC – found in pigs, cattle, dogs and cats); enterohaemorrhagic (EHEC – found in humans, cattle, and goats, attacking porcine strains that colonize the gut in a manner similar to human EPEC strains) and enteroaggregative E. coli (EAggEC – found only in humans).
E. coli O157:H7 was first recognized as a pathogen as a result of an outbreak of unusual gastrointestinal illness in 1982. The outbreak was traced to contaminated hamburgers, and the illness was similar to other incidents in the United States and Japan. The etiologic agent of the illness was identified as a rare O157:H7 serotype of Escherichia coli in 1983. This serotype had only been isolated once before, from a sick patient in 1975.
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Exceptional value for money Rapid detection of all clinically relevant subtypes Positive copy number standard curve for quantification Highly specific detection profile High priming efficiency Broad dynamic detection range (>6 logs) Sensitive to < 100 copies of target
Accurate controls to confirm findings
Gel images of different ranges of library size selection. Sheared human genomic DNA was used as input.
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Library size selection is an enrichment of a specific range of library sizes for NGS library preparations. The NGS library preparation is related to the quality of the sequencing data. Precise NGS library size selection can increase sequencing efficiency, improve data quality, and reduce costs.
There are two types of sequencing technologies: short-read sequencing and long-read sequencing. Short-read sequencing uses DNA libraries that contain small insert DNA fragments of similar sizes, usually several hundred base pairs. The sequencing efficiency can be improved if the DNA size selection is in the right range. Cat.# 20104S and 20104L are the best kits for NGS library size selection of illumina paired-end 100 (PE100) sequencing with 100-200 bp library inserts; Cat.# 20105S and 20105L are the best kits for NGS library size selection of illumina paired-end 150 (PE150) sequencing with 150-300 bp library inserts; and Cat.# 20106S and 20106L are the best kits for NGS library size selection of illumina paired-end 300 (PE300) sequencing with 300-600 bp library inserts.
Long-read sequencing uses a large DNA fragment as input and makes very long reads. Usually, library size selection is preferred to remove smaller fragments. Cat.# 20110S and 20110L are the best kits for long-read sequencing size selection with DNA sizes >5 kb, and Cat.# 20111S and 20111L are the best kits for long-read sequencing size selection with DNA sizes >10 kb.
The magnetic beads, or SPRI (Solid Phase Reversible Immobilization) beads, is well used for the purification of DNA due to their reversible DNA binding. The NGS library can be size-selected by the magnetic beads or SPRI beads. The properties of the magnetic beads can be changed for a specific range of DNA binding. The contaminants and other unwanted components in the libraries can also be removed during size selection.
Specific ranges of NGS libraries can be selected using magnetic beads with different buffer compositions. The first DNA-beads binding step, also called the right-side clean-up, removes large NGS library fragments. The large NGS library fragments that bind to the beads are discarded with the beads pellet. The desired NGS library fragments in the supernatant are transferred to a new well, and new beads are added to the supernatant for the second beads-DNA binding, also called the left-side clean-up. After the rinsing step, the NGS library fragments with the dual selection are eluted in water or an appropriate buffer. The magnetic beads method has great advantages over time-consuming column purification and tedious gel-based purification.
NGS library size selection with dual clean-ups.
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Library size selection for long-read sequencing only requires a single clean-up. In this case, only the large library fragments are bound to the beads, while other small library fragments are discarded with the supernatant. The selected larger library fragments are eluted in water or an appropriate buffer after the rinsing step.
NGS library size selection with single clean-up for >5 kb and >10 kb libraries.
Propargyl-PEG7-NHS ester contains a propargyl group and an NHS ester. As an amine reactive reagent, this product can be used for derivatizing peptides, antibodies, amine coated surfaces etc. In the presence of copper catalyst, propargyl group reacts with azide to yield a stable triazole linkage. The PEG units help increase the hydrophilicity of the reagent. Reagent grade, for research purpose. Please contact us for GMP-grade inquiries.
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Propargyl-PEG7-NHS ester contains a propargyl group and an NHS ester. As an amine reactive reagent, this product can be used for derivatizing peptides, antibodies, amine coated surfaces etc. In the presence of copper catalyst, propargyl group reacts with azide to yield a stable triazole linkage. The PEG units help increase the hydrophilicity of the reagent. Reagent grade, for research purpose. Please contact us for GMP-grade inquiries.
