title: Crystallization and preliminary X-ray analysis of the full-size cubic core of pig 2-oxoglutarate dehydrogenase complex.
abstract: The full-length (untruncated) dihydrolipoamide succinyltransferase from pig heart was crystallized by the hanging-drop vapour-diffusion method. X-ray diffraction patterns indicate that the crystal belongs to space group I432, with unit-cell parameter a = 189.9 A. The crystal structure has been preliminarily solved at 7 A resolution by the molecular-replacement method. The unit cell contains two cubic cores, in each of which 24 subunits of E2 are associated according to crystallographic 432 symmetry. At the corners of each cubic core, the catalytic domains of E2s form a trimer through tight interactions around the crystallographic threefold axes. In the electron-density maps, many small broad peaks are observed in regions expected to contain the remaining N-terminal domains (the E1/E3-binding domain and the lipoyl domain), suggesting flexibility of these domains relative to the core. The architecture of the cubic core is similar to that of the other truncated E2s. In the unit cell, however, the core-core contact occurs in a different direction from that found for the truncated proteins.
authors.affiliation: Department of Environmental Science, College of Science and Engineering, Iwaki Meisei University, Chuodai-iino, Iwaki 970-8551, Japan.
authors.forename: Kaoru
authors.initials: K
authors.lastname: Suzuki
authors.forename: Wataru
authors.initials: W
authors.lastname: Adachi
authors.forename: Noriyo
authors.initials: N
authors.lastname: Yamada
authors.forename: Masaru
authors.initials: M
authors.lastname: Tsunoda
authors.forename: Kichiko
authors.initials: K
authors.lastname: Koike
authors.forename: Masahiko
authors.initials: M
authors.lastname: Koike
authors.forename: Takeshi
authors.initials: T
authors.lastname: Sekiguchi
authors.forename: Akio
authors.initials: A
authors.lastname: Takénaka
mesh_terms: D000818:Animals; D003460:Crystallization; D007655:Ketoglutarate Dehydrogenase Complex / Q000737:chemistry*; D008958:Models, Molecular; D008970:Molecular Weight; D009097:Multienzyme Complexes / Q000737:chemistry*; D011487:Protein Conformation; D013552:Swine; D014961:X-Ray Diffraction
chemical_list: D009097:Multienzyme Complexes; D007655:Ketoglutarate Dehydrogenase Complex