MCherry Protein – MCherry fluorescent protein(mCherry)

General information on MCherry protein

MCherry protein is a member of mFruits family of proteins which consists of monomeric red fluorescent proteins. These proteins are often used as tags to exploit different organelles using fluorescence spectroscopy. MCherry protein is capable of absorbing light between 540-50 nm and emits light in return in a wavelength range of 550-650 nm. MCherry protein has been used to visualize genes and further analyze their function. One main advantage of using fluorescent proteins such as mCherry and mRFPs, is that, because of their lower molecular weight, that have the tendency to fold fasters than tetramers. This results in monomeric fluorescent proteins that disturb the target less.

The structure of mCherry protein consists of 3 alpha helices and the beta barrel that is made of 13 beta sheets. Its chromophore contains three amino acids, glycine, methionine and tyrosine. These amino acids are post-translationally modified into imidazoline. The red-shifted absorbance and emission of mCherry protein is due to its extended p-electron conjugation.

MCherry protein can be used as an intracellular probe in fluorescence microscopy. However, possible interactions between the tagged protein and the fluorescent protein can disturb the targeting process or the function of the protein of interest. mCherry protein can be used as an acceptor for hetero-FRET (also known as fluorescence resonance energy transfer) and probe for homo-FRET experiments. FRET is a nonradiative phenomenon that consists of energy being transferred from the donor (fluorophore) to the acceptor (chromophore). The efficiency of this lab technique depends of the distance between the donor and the acceptor.
MCherry protein was developed in order to study bacterial gene expression in L.pneumophila, a Gram-negative pathogen responsible for the Legionnaire’s Disease. Because mCherry protein doesn’t interfere with other plasmids and doesn’t alter the intracellular, this protein has been frequently used for constitutive gene expression in a wide range of Gram-negative bacterial species.