Redirecting photosynthetic electron flux in the cyanobacterium Synechocystis sp. PCC 6803 by the deletion of flavodiiron protein Flv3.

Oxygen-evolving photoautotrophic organisms， like cyanobacteria， protect their photosynthetic machinery by a number of regulatory mechanisms， including alternative electron transfer pathways. Despite the importance in modulating the electron flux distribution between the photosystems， alternative electron transfer routes may compete with the solar-driven production of CO-derived target chemicals in biotechnological systems under development. This work focused on engineered cyanobacterial Synechocystis sp. PCC 6803 strains， to explore possibilities to rescue excited electrons that would normally be lost to molecular oxygen by an alternative acceptor flavodiiron protein Flv1/3-an enzyme that is natively associated with transfer of electrons from PSI to O， as part of an acclimation strategy towards varying environmental conditions.