title: X-ray crystal structures of Enterococcus faecalis thymidylate synthase with folate binding site inhibitors.
abstract: Infections caused by Enterococcus faecalis (Ef) represent nowadays a relevant health problem. We selected Thymidylate synthase (TS) from this organism as a potential specific target for antibacterial therapy. We have previously demonstrated that species-specific inhibition of the protein can be achieved despite the relatively high structural similarity among bacterial TSs and human TS. We had previously obtained the EfTS crystal structure of the protein in complex with the metabolite 5-formyl-tetrahydrofolate (5-FTHF) suggesting the protein role as metabolite reservoir; however, protein-inhibitors complexes were still missing. In the present work we identified some inhibitors bearing the phthalimidic core from our in-house library and we performed crystallographic screening towards EfTS. We obtained two X-ray crystallographic structures: the first with a weak phthalimidic inhibitor bound in one subunit and 5-hydroxymethylene-6-hydrofolic acid (5-HMHF) in the other subunit; a second X-ray structure complex with methotrexate. The structural information achieved confirm the role of EfTS as an enzyme involved in the folate pool system and provide a structural basis for structure-based drug design.
authors: Dipartimento di Farmacia-Scienze del Farmaco, Università degli Studi di Bari "Aldo Moro", Via Orabona 4, 70125 Bari, Italy.
authors: Alessia
authors: A
authors: Catalano
authors: Dipartimento di Scienze della Vita, Università degli Studi di Modena e Reggio Emilia, Via Campi 103, 41125 Modena, Italy.
authors: Rosaria
authors: R
authors: Luciani
authors: Dipartimento di Farmacia-Scienze del Farmaco, Università degli Studi di Bari "Aldo Moro", Via Orabona 4, 70125 Bari, Italy.
authors: Alessia
authors: A
authors: Carocci
authors: Dipartimento di Scienze della Vita, Università degli Studi di Modena e Reggio Emilia, Via Campi 103, 41125 Modena, Italy.
authors: Debora
authors: D
authors: Cortesi
authors: Dipartimento di Biotecnologie, Chimica e Farmacia, Università degli Studi di Siena, Via Aldo Moro 2, 53100 Siena, Italy.
authors: Cecilia
authors: C
authors: Pozzi
authors: Dipartimento di Scienze della Vita, Università degli Studi di Modena e Reggio Emilia, Via Campi 103, 41125 Modena, Italy.
authors: Chiara
authors: C
authors: Borsari
authors: Dipartimento di Scienze della Vita, Università degli Studi di Modena e Reggio Emilia, Via Campi 103, 41125 Modena, Italy. Electronic address: stefania.ferrari@unimore.it.
authors: Stefania
authors: S
authors: Ferrari
authors: Dipartimento di Biotecnologie, Chimica e Farmacia, Università degli Studi di Siena, Via Aldo Moro 2, 53100 Siena, Italy. Electronic address: stefano.mangani@unisi.it.
authors: Stefano
authors: S
authors: Mangani
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology*; D001665:Binding Sites / Q000187:drug effects; D018360:Crystallography, X-Ray; D015195:Drug Design; D013293:Enterococcus faecalis / Q000187:drug effects / Q000201:enzymology*; D004791:Enzyme Inhibitors / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology*; D005492:Folic Acid / Q000378:metabolism*; D006801:Humans; D008958:Models, Molecular; D011487:Protein Conformation; D013763:Tetrahydrofolates / Q000378:metabolism; D013940:Thymidylate Synthase / Q000037:antagonists & inhibitors* / Q000737:chemistry* / Q000378:metabolism
chemical_list: D000900:Anti-Bacterial Agents; D004791:Enzyme Inhibitors; D013763:Tetrahydrofolates; C030371:5,6,7,8-tetrahydrofolic acid; D005492:Folic Acid; D013940:Thymidylate Synthase
keywords: Antibacterial; Enterococcus faecalis; Enzyme inhibition; Phthalimide scaffold; Thymidylate synthase; X-ray crystallography screening