QconCAT technology

In many applications, protein quantification is essential; however, it can be a challenge…

• varied assay environments make it difficult to compare results
• customized synthetic peptides are expensive
• assays are likely to contain potential artifacts, for example, adsorption of synthetic reference peptides to vessel walls
• assay development takes too much time, especially when new antibodies have to be raised

QconCAT technology will allow you to avoid those obstacles, save time and expenses

Advatanges

Absolute quantification
Multiplex simultaneous quantification up to 100 proteins
Low cost, fast, antibody free assay
High sensitivity (up to 25 pg of protein)
Applied to samples of any nature (blood, urine, cell culture extracts, tissue samples)

Technology concept

Synthetic gene is designed to encode all
proteotypic peptides of the sample protein mixture

Gene is synthesized, subcloned into vector and
expressed in the medium with isotope
labeled amino acids

QconCAT* synthetic polypeptide labeled with stable
isotopes is purified

When mixed with the sample proteins it serves
as an internal control in mass spectrometry analysis

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*QconCAT stands for ‘Quantification concatamer’

References

[1]	Beynon R. J., Doherty M. K., Pratt J. M., Gaskell S. J., Nature Methods Vol. 2 (8), August 2005, 587-589: “Multiplexed absolute quantification in proteomics using artificial QCAT proteins of concatenated signature peptides”
[2]	Pratt J. M., Simpson D. M., Doherty M. K., Rivers J., Gaskell S. J., Beynon R. J., Nature Protocols Vol. 1 (2), 2006, 1029-1043: “Multiplexed absolute quantification for proteomics using concatenated signature peptides encoded by QconCAT genes”

Technical information for researchers and mass spectrometry experts:

Designing a QconCAT
The importance of complete proteolysis
Gene optimisation and protein expression
Isotope labelling strategies for QconCATs
Determining protein stoichiometry
Designer proteins: versatile research tools
QconCATs or synthetic/AQUA peptides?
QconCAT – Frequently asked questions