title: Structure of dihydrodipicolinate synthase of Nicotiana sylvestris reveals novel quaternary structure.
abstract: DHDPS is the first enzyme unique to the lysine biosynthetic pathway in plants and bacteria and catalyses the formation of (4S)-4-hydroxy-2,3,4,5-tetrahydro-(2S)-dipicolinic acid. It is feedback-regulated in plants by L-lysine. The crystal structure of Nicotiana sylvestris DHDPS with and without inhibitory lysine bound to the enzyme has been solved to a resolution of 2.8 A. The molecule is a homotetramer composed of a dimer of dimers. Comparison with the structure of Escherichia coli DHDPS showed a novel quaternary structure by a profound rearrangement of the dimers forming the tetramer. The crystal structure of the enzyme in the presence of L-lysine revealed substantial changes. These changes together with the novel quaternary structure provide a structural basis for the strong inhibition of plant DHDPS enzymes by L-lysine.
authors.affiliation: Max-Planck-Institut für Biochemie, Abteilung Strukturforschung, Martinsried, Germany.
authors.forename: S
authors.initials: S
authors.lastname: Blickling
authors.forename: H G
authors.initials: HG
authors.lastname: Beisel
authors.forename: D
authors.initials: D
authors.lastname: Bozic
authors.forename: J
authors.initials: J
authors.lastname: Knäblein
authors.forename: B
authors.initials: B
authors.lastname: Laber
authors.forename: R
authors.initials: R
authors.lastname: Huber
mesh_terms: D000595:Amino Acid Sequence; D001665:Binding Sites; D017124:Conserved Sequence; D004791:Enzyme Inhibitors / Q000737:chemistry / Q000378:metabolism; D004926:Escherichia coli / Q000201:enzymology; D006836:Hydro-Lyases / Q000037:antagonists & inhibitors / Q000737:chemistry* / Q000378:metabolism*; D008239:Lysine / Q000737:chemistry / Q000378:metabolism; D008958:Models, Molecular; D008969:Molecular Sequence Data; D010947:Plants, Toxic; D011487:Protein Conformation; D014026:Nicotiana / Q000201:enzymology*
chemical_list: D004791:Enzyme Inhibitors; D006836:Hydro-Lyases; C020040:4-hydroxy-tetrahydrodipicolinate synthase; D008239:Lysine