title: Multiple crystal forms of hexokinase I: new insights regarding conformational dynamics, subunit interactions, and membrane association.
abstract: Hexokinase I is comprised of homologous N- and C-terminal domains, and binds to the outer membrane of mitochondria. Reported here is the structure of a new crystal form of recombinant human hexokinase I, which complements existing crystal structures. Evidently, in some packing environments and even in the presence of glucose and glucose 6-phosphate the N-terminal domain (but not the C-terminal domain) can undergo oscillations between closed and partially opened conformations. Subunit interfaces, present in all known crystal forms of hexokinase I, promote the formation of linear chains of hexokinase I dimers. Presented is a model for membrane-associated hexokinase I, in which linear chains of hexokinase I dimers are stabilized by interactions with mitochondrial porin.
authors.affiliation: Department of Biochemistry and Biophysics, Iowa State University, Ames 50011, USA.
authors.forename: A E
authors.initials: AE
authors.lastname: Aleshin
authors.forename: H J
authors.initials: HJ
authors.lastname: Fromm
authors.forename: R B
authors.initials: RB
authors.lastname: Honzatko
mesh_terms: D002462:Cell Membrane / Q000378:metabolism*; D018360:Crystallography, X-Ray; D006593:Hexokinase / Q000737:chemistry* / Q000378:metabolism; D006801:Humans; D008565:Membrane Proteins / Q000737:chemistry / Q000378:metabolism; D011487:Protein Conformation; D011994:Recombinant Proteins / Q000737:chemistry / Q000378:metabolism
chemical_list: D008565:Membrane Proteins; D011994:Recombinant Proteins; D006593:Hexokinase