title: Crystal structure of Thermus caldophilus phosphoglycerate kinase in the open conformation.
abstract: Phosphoglycerate kinase (PGK) is a key glycolytic enzyme that catalyzes the reversible transfer of a phosphate from 1,3-bisphosphoglycerate to ADP to form 3-phosphoglycerate and ATP in the presence of magnesium. During catalysis, a conformational change occurs that brings the N- and C-domains of PGK closer together. Here we present the 1.8A crystal structure of unliganded PGK from Thermus caldophilus (Tca). Comparison of the structure of TcaPGK (open conformation) with that of Thermotoga maritima (Tma) PGK (closed conformation) revealed that the conformational change reflects a change in the interaction between the domains. We identified Arg148 as a key residue involved in open-to-closed transition. The open conformation of TcaPGK is stabilized by an interdomain salt bridge between Arg148 and Glu375. The binding of 3-PG (or maybe 1,3-BPG) disrupts this salt bridge and, in ternary complex, the formation of new salt bridge between Arg60 and Asp197 stabilizes the closed conformation.
authors.affiliation: Department of Life Science, Gwangju Institute of Science and Technology, Gwangju 500-712, Republic of Korea.
authors.forename: Jun Hyuck
authors.initials: JH
authors.lastname: Lee
authors.forename: Young Jun
authors.initials: YJ
authors.lastname: Im
authors.forename: Jungdon
authors.initials: J
authors.lastname: Bae
authors.forename: Dooil
authors.initials: D
authors.lastname: Kim
authors.forename: Mun-Kyoung
authors.initials: MK
authors.lastname: Kim
authors.forename: Gil Bu
authors.initials: GB
authors.lastname: Kang
authors.forename: Dae-Sil
authors.initials: DS
authors.lastname: Lee
authors.forename: Soo Hyun
authors.initials: SH
authors.lastname: Eom
mesh_terms: D003198:Computer Simulation; D003461:Crystallography; D008956:Models, Chemical; D008958:Models, Molecular; D010735:Phosphoglycerate Kinase / Q000737:chemistry* / Q000648:ultrastructure*; D011487:Protein Conformation; D013824:Thermus / Q000201:enzymology*
chemical_list: D010735:Phosphoglycerate Kinase