Epicocconone is a long
Stokes' shift fluorogenic Fluorogenic describes a property of chemical compounds which are initially not fluorescent, but become fluorescent through a chemical reaction, typically through an intermolecular covalent reaction which binds the now fluorescent compound to a targe ...
natural product
A natural product is a natural compound or substance produced by a living organism—that is, found in nature. In the broadest sense, natural products include any substance produced by life. Natural products can also be prepared by chemical s ...
found in the fungus ''
Epicoccum nigrum''. Though weakly fluorescent in water (green emission, 520
nm) it reacts
covalently
A covalent bond is a chemical bond that involves the sharing of electrons to form electron pairs between atoms. These electron pairs are known as shared pairs or bonding pairs. The stable balance of attractive and repulsive forces between atoms ...
yet
reversibly with
primary amines
In chemistry, amines (, ) are organic compounds that contain carbon-nitrogen bonds. Amines are formed when one or more hydrogen atoms in ammonia are replaced by alkyl or aryl groups. The nitrogen atom in an amine possesses a lone pair of elec ...
such as those in
protein
Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residue (biochemistry), residues. Proteins perform a vast array of functions within organisms, including Enzyme catalysis, catalysing metab ...
s to yield a product with a strong
orange-red emission (610 nm).
Epicoconone is notable because it the first covalent/
reversible/turn-on fluorophore to be discovered and is a natural product with a new fluorescent scaffold. It is also cell membrane permeable, unlike many other fluorophores, and subsequently can be used in ''
in vivo
Studies that are ''in vivo'' (Latin for "within the living"; often not italicized in English) are those in which the effects of various biological entities are tested on whole, living organisms or cells, usually animals, including humans, an ...
'' (live cell) applications.
Additionally, this dye can be used as a sensitive total protein stain for 1D and
2D electrophoresis,
quantitative determination of protein concentration, making it a powerful loading control for
Western blot
The western blot (sometimes called the protein immunoblot), or western blotting, is a widely used analytical technique in molecular biology and immunogenetics to detect specific proteins in a sample of tissue homogenate or extract. Besides detect ...
s.
Synthetic variant
In addition to the natural variant from the fungus, there are several synthetic analogs.
With respect to protein staining properties there are few differences between natural and synthetic analogs.
Reaction
References
{{Reflist
Fluorescent dyes