Abstract

The PsbM (3.9 kDa) and PsbY (4.2 kDa) proteins are membrane-spanning, single-helix, subunits associated with the chlorophyll-binding CP47 pre-complex of photosystem II (PSII). Removal of PsbM resulted in accumulation of PSII pre-assembly complexes and impaired electron transfer between the primary (QA) and secondary (QB) plastoquinone electron acceptors of PSII indicating that the QB-binding site and bicarbonate binding to the non-heme iron were altered in this strain. Removal of PsbY alone had only a minor impact on PSII activity but deleting PsbY in the ΔPsbM background led to additional modification of the acceptor side resulting in ΔPsbM:ΔPsbY cells being susceptible to photodamage and this required protein synthesis for recovery. Addition of bicarbonate was able to compensate for the light-induced damage in ΔPsbM:ΔPsbY cells potentially re-occupying the modified bicarbonate-binding site in the ΔPsbM:ΔPsbY strain and complementation of ΔPsbM:ΔPsbY cells with the psbY gene restored the ΔPsbM phenotype.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.