Characterization of the Synechocystis PCC 6803 Fluorescence Recovery Protein involved in photoprotection

► The Fluorescence Recovery Protein (FRP) switches off OCP-related photoprotection. ► It was proposed that Synechocystis FRP has a 25 amino-acid N-terminal prolongation. ► Our work shows that FRP has no such prolongation and starts at Met26. ► Short FRP-starting at Met26 can be isolated from Synechocystis and is active. ► High FRP to OCP ratio inhibits photoprotection.