Figure 8. Scheme of the reversible photoswitching mechanism of asFP595 proposed in this work.
The fluorescent state Zcis is highlighted. The green arrows indicate ground state equilibria, whereas the red arrows indicate excited state processes. The major protonation states are the zwitterionic and the anionic chromophores in the trans conformation, and the neutral chromophore in the cis conformation, as indicated in the square brackets.