5mac

Crystal structure of decameric Methanococcoides burtonii Rubisco complexed with 2-carboxyarabinitol bisphosphateCrystal structure of decameric Methanococcoides burtonii Rubisco complexed with 2-carboxyarabinitol bisphosphate

Structural highlights 5mac is a 5 chain structure with sequence from Methanococcoides burtonii. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Method: X-ray diffraction, Resolution 2.6Å Ligands: , , , Resources: FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT Function Q12TQ0_METBU Publication Abstract from PubMed The catalytic inefficiencies of the CO2-fixing enzyme ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) often limit plant productivity. Strategies to engineer more efficient plant Rubiscos have been hampered by evolutionary constraints, prompting interest in Rubisco isoforms from non-photosynthetic organisms. The methanogenic archaeon Methanococcoides burtonii contains a Rubisco isoform that functions to scavenge the ribulose-1,5-bisphosphate (RuBP) byproduct of purine/pyrimidine metabolism. The crystal structure of M. burtonii Rubisco (MbR) presented here at 2.6 A resolution is composed of catalytic large subunits (LSu) assembled into pentamers of dimers, (L2)5, and differs from Rubiscos from higher plants where LSus are glued together by small subunits (SSu) into hexadecameric L8S8 enzymes. MbR contains a unique 29-amino-acid insertion near the C-terminus, which folds as a separate domain in the structure. This domain, which is visualized for the first time in this study, is located in a similar position to SSus in L8S8 enzymes between LSus of adjacent L2 dimers, where negatively charged residues co-ordinate around a Mg2+ ion in a fashion that suggests this domain may be important for the assembly process. The Rubisco assembly domain is thus an inbuilt SSu mimic that concentrates L2 dimers. MbR assembly is ligand-stimulated and we show that only 6-carbon molecules with a particular stereochemistry at the C3 carbon can induce oligomerization. Based on MbR structure, subunit arrangement, sequence, phylogenetic distribution and function, MbR and a subset of Rubiscos from the Methanosarcinales order are proposed to belong to a new Rubisco sub-group, named form IIIB. A Unique Structural Domain in Methanococcoides burtonii Rubisco Acts as a Small-subunit Mimic.,Gunn LH, Valegard K, Andersson I J Biol Chem. 2017 Jan 30. pii: jbc.M116.767145. doi: 10.1074/jbc.M116.767145. PMID:28154188 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See Also RuBisCO 3D structures

spinqualitylabelsall models 5mac, resolution 2.60Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image