title: X-ray structure of prephenate dehydratase from Streptococcus mutans.
abstract: Prephenate dehydratase is a key enzyme of the biosynthesis of L-phenylalanine in the organisms that utilize shikimate pathway. Since this enzymatic pathway does not exist in mammals, prephenate dehydratase can provide a new drug targets for antibiotics or herbicide. Prephenate dehydratase is an allosteric enzyme regulated by its end product. The enzyme composed of two domains, catalytic PDT domain located near the N-terminal and regulatory ACT domain located near the C-terminal. The allosteric enzyme is suggested to have two different conformations. When the regulatory molecule, phenylalanine, is not bound to its ACT domain, the catalytic site of PDT domain maintain open (active) state conformation as Sa-PDT structure. And the open state of its catalytic site become closed (allosterically inhibited) state if the regulatory molecule is bound to its ACT domain as Ct-PDT structure. However, the X-ray structure of prephenate dehydratase from Streptococcus mutans (Sm-PDT) shows that the catalytic site of Sm-PDT has closed state conformation without phenylalanine molecule bound to its regulatory site. The structure suggests a possibility that the binding of phenylalanine in its regulatory site may not be the only prerequisite for the closed state conformation of Sm-PDT.
authors.affiliation: College of Pharmacy, Chungbuk National University, Chungbuk, 361-763, Republic of Korea.
authors.forename: Min Hyung
authors.initials: MH
authors.lastname: Shin
authors.forename: Hyung-Keun
authors.initials: HK
authors.lastname: Ku
authors.forename: Jin Sue
authors.initials: JS
authors.lastname: Song
authors.forename: Saehae
authors.initials: S
authors.lastname: Choi
authors.forename: Se Young
authors.initials: SY
authors.lastname: Son
authors.forename: Hyo-Jin
authors.initials: HJ
authors.lastname: Yang
authors.forename: Hee-Dai
authors.initials: HD
authors.lastname: Kim
authors.forename: Sook-Kyung
authors.initials: SK
authors.lastname: Kim
authors.forename: Il Yeong
authors.initials: IY
authors.lastname: Park
authors.forename: Soo Jae
authors.initials: SJ
authors.lastname: Lee
mesh_terms: D018360:Crystallography, X-Ray / Q000379:methods; D011302:Prephenate Dehydratase / Q000737:chemistry*; D013295:Streptococcus mutans / Q000201:enzymology*
chemical_list: D011302:Prephenate Dehydratase