title: Methylidene-imidazolone: a novel electrophile for substrate activation.
abstract: The recent three-dimensional structure of histidine ammonia-lyase revealed that the enzyme contains a 3,5-dihydro-5-methylidene-4H-imidazol-4-one (MIO) ring, which forms autocatalytically from an Ala-Ser143-Gly triad. This novel prosthetic group, which is also present in phenylalanine ammonia-lyase, activates substrates by electrophilic interaction. Modern analytical methods, theoretical calculations and molecular biology tools have given further insight into the mode of action of MIO.
authors.affiliation: Institute for Organic Chemistry, Budapest University of Technology and Economics, H-1111, Budapest, Gellért tér 4, Hungary. poppe.szk@chem.bme.hu
authors.forename: L
authors.initials: L
authors.lastname: Poppe
mesh_terms: D018360:Crystallography, X-Ray; D049452:Green Fluorescent Proteins; D006638:Histidine Ammonia-Lyase / Q000737:chemistry* / Q000378:metabolism; D007093:Imidazoles / Q000737:chemistry*; D008164:Luminescent Proteins / Q000378:metabolism; D008956:Models, Chemical; D010650:Phenylalanine Ammonia-Lyase / Q000737:chemistry / Q000378:metabolism
chemical_list: D007093:Imidazoles; D008164:Luminescent Proteins; C117197:imidazolone; D049452:Green Fluorescent Proteins; D010650:Phenylalanine Ammonia-Lyase; D006638:Histidine Ammonia-Lyase