title: Identification of novel allosteric regulators of human-erythrocyte pyruvate kinase.
abstract: Erythrocyte pyruvate kinase (PK) is an important glycolytic enzyme, and manipulation of its regulatory behavior by allosteric modifiers is of interest for medicinal purposes. Human-erythrocyte PK was expressed in Rosetta cells and purified on an Ni-NTA column. A search of the small-molecules database of the National Cancer Institute (NCI), using the UNITY software, led to the identification of several compounds with similar pharmacophores as fructose-1,6-bisphosphate (FBP), the natural allosteric activator of the human kinases. The compounds were subsequently docked into the FBP binding site using the programs FlexX and GOLD, and their interactions with the protein were analyzed with the energy-scoring function of HINT. Seven promising candidates, compounds 1-7, were obtained from the NCI, and subjected to kinetics analysis, which revealed both activators and inhibitors of the R-isozyme of PK (R-PK). The allosteric effectors discovered in this study could prove to be lead compounds for developing medications for the treatment of hemolytic anemia, sickle-cell anemia, hypoxia-related diseases, and other disorders arising from erythrocyte PK malfunction.
authors.affiliation: Department of Medicinal Chemistry, School of Pharmacy, and Institute for Structural Biology and Drug Discovery, Virginia Commonwealth University, Richmond, VA 23298, USA.
authors.forename: Shilpa S
authors.initials: SS
authors.lastname: Kharalkar
authors.forename: Gajanan S
authors.initials: GS
authors.lastname: Joshi
authors.forename: Faik N
authors.initials: FN
authors.lastname: Musayev
authors.forename: Micaela
authors.initials: M
authors.lastname: Fornabaio
authors.forename: Donald J
authors.initials: DJ
authors.lastname: Abraham
authors.forename: Martin K
authors.initials: MK
authors.lastname: Safo
mesh_terms: D000494:Allosteric Regulation / Q000187:drug effects / Q000502:physiology*; D001665:Binding Sites / Q000187:drug effects / Q000502:physiology; D004912:Erythrocytes / Q000737:chemistry* / Q000201:enzymology* / Q000378:metabolism; D005635:Fructosediphosphates / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology; D006801:Humans; D017433:Protein Structure, Secondary / Q000502:physiology; D011770:Pyruvate Kinase / Q000737:chemistry* / Q000378:metabolism
chemical_list: D005635:Fructosediphosphates; D011770:Pyruvate Kinase; C029063:fructose-1,6-diphosphate