The small CAB-like proteins of the cyanobacterium Synechocystis sp. PCC 6803: Transcriptomic, proteomic and metabolomic analyses reveal new insights into their function
(English)Manuscript (preprint) (Other academic)
The five small CAB-like proteins (ScpA-E) of the cyanobacterium Synechocystis sp. PCC 6803 consist of one transmembrane helix and belong to the light-harvesting like family. While in wild type they are induced by various stresses, in cells with Photosystem I (PSI) -less background the SCPs are constitutively expressed. Here we performed a detailed comparison of a PSI-less control strain with a strain depleted of PSI and all SCPs, with the aim to elucidate the function of the SCPs within Photosystem II. Electron microscopical immages showed a drastic alteration of the cellular organization, visible by a rough surface and few thylakoid membranes in the PSI-less/ScpABCDE- strain. Immunoblots pointed to a decreased amount of PSII per cell volume. Deletion of the scp genes also affected the carbon- and nitrogen-balance and thereby the carbohydrate accumulation at the expenses of protein- and chlorophyll-synthesis as judged by transcriptomic and metabolomic analyses. Our results show that SCPs ensure a correct assembly/repair of PSII and therefore are important for the adaptation to environmental stresses - especially during the generation of reactive oxygen species.
Photosystem II, Synechocystis sp. PCC 6803, small CAB-like proteins, carbon/nitrogen balance, stress adaptation
IdentifiersURN: urn:nbn:se:umu:diva-59784OAI: oai:DiVA.org:umu-59784DiVA: diva2:556614