6lrs
Cryo-EM structure of RbcL8-RbcS4 from Anabaena sp. PCC 7120Cryo-EM structure of RbcL8-RbcS4 from Anabaena sp. PCC 7120
Structural highlights
FunctionRBS_NOSS1 RuBisCO catalyzes two reactions: the carboxylation of D-ribulose 1,5-bisphosphate, the primary event in carbon dioxide fixation, as well as the oxidative fragmentation of the pentose substrate. Both reactions occur simultaneously and in competition at the same active site (By similarity). Publication Abstract from PubMedThe folding and assembly of RuBisCO, the most abundant enzyme in nature, needs a series of chaperones, including the RuBisCO accumulation factor Raf1, which is highly conserved in cyanobacteria and plants. Here, we report the crystal structures of Raf1 from cyanobacteria Anabaena sp. PCC 7120 and its complex with RuBisCO large subunit RbcL. Structural analyses and biochemical assays reveal that each Raf1 dimer captures an RbcL dimer, with the C-terminal tail inserting into the catalytic pocket, and further mediates the assembly of RbcL dimers to form the octameric core of RuBisCO. Furthermore, the cryo-electron microscopy structures of the RbcL-Raf1-RbcS assembly intermediates enable us to see a dynamic assembly process from RbcL8Raf18 to the holoenzyme RbcL8RbcS8. In vitro assays also indicate that Raf1 can attenuate and reverse CcmM-mediated cyanobacterial RuBisCO condensation. Combined with previous findings, we propose a putative model for the assembly of cyanobacterial RuBisCO coordinated by the chaperone Raf1. Molecular basis for the assembly of RuBisCO assisted by the chaperone Raf1.,Xia LY, Jiang YL, Kong WW, Sun H, Li WF, Chen Y, Zhou CZ Nat Plants. 2020 May 25. pii: 10.1038/s41477-020-0665-8. doi:, 10.1038/s41477-020-0665-8. PMID:32451445[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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