title: Tertiary structure of plant RuBisCO: domains and their contacts.
abstract: The three-dimensional structure of ribulose-1,5-biphosphate carboxylase-oxygenase (RuBisCO), has been determined at 2.6 A resolution. This enzyme initiates photosynthesis by combining carbon dioxide with ribulose bisphosphate to form two molecules of 3-phosphoglycerate. In plants, RuBisCO is built from eight large (L) and eight small (S) polypeptide chains, or subunits. Both S chains and the NH2-terminal domain (N) of L are antiparallel beta, "open-face-sandwich" domains with four-stranded beta sheets and flanking alpha helices. The main domain (B) of L is an alpha/beta barrel containing most of the catalytic residues. The active site is in a pocket at the opening of the barrel that is partly covered by the N domain of a neighboring L chain. The domain contacts of the molecule and its conserved residues are discussed in terms of this structure.
mesh_terms: D000595:Amino Acid Sequence; D001665:Binding Sites; D046911:Macromolecular Substances; D008969:Molecular Sequence Data; D010944:Plants / Q000201:enzymology*; D011487:Protein Conformation; D012247:Rhodospirillum rubrum / Q000201:enzymology; D012273:Ribulose-Bisphosphate Carboxylase; D014961:X-Ray Diffraction
chemical_list: D046911:Macromolecular Substances; D012273:Ribulose-Bisphosphate Carboxylase