Cyan-to-green photoswitchable fluorescent protein PS-CFP2

- Irreversible photoconversion from a cyan to a green fluorescent form
- High contrast of photoconversion
- High pH stability allowing labeling of acidic organelles
- Recommended for tracking cell, organelle, and protein movement, and for determination of protein half-life

Main properties

Normalized excitation (thin line) and emission (thick line) for non-activated (cyan) and activated (green) spectra. Download PS-CFP2 spectra (xls)

CHARACTERISTIC before  /  after photoactivation *Brightness is a product of extinction coefficient and quantum yield, divided by 1000. Fluorescence color cyan   /   green Excitation maximum, nm 400   /   490 Emission maximum, nm 468   /   511 Quantum yield 0.2   /   0.23 Extinction coefficient, M-1cm-1 43 000   /   47 000 Brightness* 8.6   /   10.81 pKa 4.3   /   6.1 Activating light UV-violet (e.g. 405 nm) Calculated contrast, fold up to 2000 Structure monomer Cell toxicity not observed Aggregation no Maturation rate at 37°C fast Molecular weight, kDa 27 Polypeptide length, aa 238 Main advantages Bright and pH stable routin cyan label, monomeric high-contrast irreversibly photoswitchable tag suitable for protein tracking