- Large Stokes Shift
- Unique Spectrum
CoralHue® dKeima570, originally cloned from the stony coral Montipora sp.(Komon-sango in Japanese), absorbs light maximally at 440 nm and emits orange-red light at 570 nm. Because of the extremely large Stokes shift (130 nm) of CoralHue® dKeima570, the maximum fluorescence can be obtained by the maximum excitation without sacrificing either excitation or fluorescence.
Although several fluorescent proteins have a large Stokes shift, they have green fluorescence as a result of excitation with UV light at around 380 nm. However, the use of such toxic UV light is not suitable for observation in living organisms. Keima is the first red fluorescent protein having a large Stokes shift.
The combination of orange-red emission, a large Stokes shift, stability at 37°C in eukaryotic cells, and being dimeric make CoralHue® dKeima570 a superb reporter protein for labeling subcellular structures in multicolor fluorescence analyses. The orange-red fluorescence is stable under normal aerobic conditions.
Note: The file is in a tab-delimited text format. It contains values of the wavelength (1nm spacing) and brightness (fluorescence intensity peak value normalized to 1). Use a spreadsheet program to create a spectrum that will help you in choosing the appropriate excitation filter, dichroic mirror and fluorescence filter.
|Number of amino acid
|Excit./Emiss. maxima (nm)
|Molar extinction coefficient (M-1cm-1)
||14,000 (492 nm)
|Fluorescence quantum yield
*1Brightness: Molar Extinction Coefficient ×Fluorescence Quantum Yield / 1000
*2Toxicity when expressed in HeLa cells
- Kogure T, Karasawa S, Araki T, Saito K, Kinjo M, Miyawaki A. A fluorescent variant of a protein from the stony coral Montipora facilitates dual-color single-laser fluorescence cross-correlation spectroscopy.
Nat Biotechnol. 2006 (5):577-81. PMID: 16648840