We are pleased to present you an improved method of labeling proteins by fluorescence, with a new synthetic fluorescent indicator, EpicoccoStab.
The applications are protein quantification assay and protein gel staining in gel electrophoresis, but others are possible, like blots [2] or in cells staining [3].

Epicocconone, a natural compound of EpicoccoStab

Epicocconone is a unique fluorochrome produced by the fungus Epicoccum nigrum,  widely used in biotechnology because of its large Stokes shift and lack of fluorescence in its unconjugated state [1].  However, the low photostability and quantum yields of this natural fluorophore have limited its wider use.

  • The Epicoccone reversibly binds to the protein (specific for lysine, arginine, and histidine) :épicoccone fluoProbes


  •  Reversible attachment of peptide [4]

  • It then has a broad spectral shift, which facilitates measurment of the fluorescent signal.

epicoccone_fluoProbes_Interchim_Blog_0716The EpicoccoStab, adds to the strengths of the decisive advantages to epicocconone

The kit of protein dosage of EpicoccoStab uses an analogue of the epicocconone, modified to increase the photostability and the quantum efficiency compared to the natural product.

  • Increased Sensitivity: the solution assay detects 40pg of proteins with a wide dynamic range (up to + 100 µg/ml). It can also detect peptides, unlike competing methods.
  • The fluorescence signal is stable more than 5 hours. Furthermore, the reagent is perfectly stable in solution.
  • The EpicoccoStab kit uses a simple and fast protocol (60min).
  • The reagent is safe, and biodegradable!
  • The labeled proteins are not modified or degraded by EpicoccoStab dye, and can be retrieved in their native form. The method thus is particularly suitable for the quantification of proteins or digested peptides before N-terminal sequencing.

Staining proteomic gels with synthetic analog showed significant lowering of the detection limit and a 30% increase in the number of detected low-abundance proteins. The EpicoccoStab will substantially improve the discovery rate of biomarker needles in the proteomic haystack.

Know more:

  • [1] Bell PJ et al., Epicocconone, a novel fluorescent compound from the fungus epicoccum nigrum, J Am Chem Soc. 6;125(31):9304-5 (2003)
  • [2] Moritz CP et al., Epicocconone staining: a powerful loading control for Western blots, Proteomics 14(11):1444 (2014)
  • [3] Notice d’application de l’épicocconone
  • [4] Coghlan DR et al., Mechanism of reversible fluorescent staining of protein with epicocconone, Org Lett. 9;7(12):2401-4. (2005)
  • [5] Moritz C.P. et al. Epicocconone staining: a powerful loading control for Western blots, Proteomics, Vol. 14, Issue 2-3, p. 162–8, (2014)
  • [6] Peixoto P. et al., Design and Synthesis of Epicocconone Analogues with Improved Fluorescence Properties, J. Am. Chem. Soc., 136 (43), pp 15248–15256 (2014)