title: Overexpression, crystallization and preliminary X-ray crystallographic analysis of D-ribose-5-phosphate isomerase from Clostridium thermocellum.
abstract: Rare sugars are used for many industrial and medical purposes and are produced by the interconversion between aldoses and ketoses catalyzed by sugar and sugar-phosphate isomerases. Recently, Clostridium thermocellum d-ribose-5-phosphate isomerase (CTRPI), an aldose-ketose isomerase, was cloned in order to synthesize d-allose and its substrate specificity was further characterized for industrial usage. CTRPI has a novel substrate specificity that differs from those of other isomerases, which have broad substrate specificities. CTRPI prefers aldose substrates such as l-talose, d-ribose and d-allose. CTRPI was purified and crystallized in order to determine its three-dimensional structure and thus to elucidate its enzymatic reaction mechanism and understand its substrate specificity. The crystal belonged to the trigonal space group P3(2)21, with unit-cell parameters a = b = 69.5, c = 154.4 angstrom, and diffracted to 1.9 angstrom resolution. According to Matthews coefficient calculations, the crystallographic structure consists of a dimer in the asymmetric unit, with a V(M) of 3.2 angstrom(3) Da(-1) and a solvent content of 61.7%.
authors.affiliation: Department of Advanced Technology Fusion, Konkuk University, Hwayang-dong, Gwangjin-gu, Seoul, Republic of Korea.
authors.forename: Junho
authors.initials: J
authors.lastname: Jung
authors.forename: Soo Jin
authors.initials: SJ
authors.lastname: Yeom
authors.forename: Jisun
authors.initials: J
authors.lastname: Kim
authors.forename: Jin Kwang
authors.initials: JK
authors.lastname: Kim
authors.forename: Sampath
authors.initials: S
authors.lastname: Natarajan
authors.forename: Yeh Jin
authors.initials: YJ
authors.lastname: Ahn
authors.forename: Sang Boem
authors.initials: SB
authors.lastname: Lim
authors.forename: Deok Kun
authors.initials: DK
authors.lastname: Oh
authors.forename: Lin Woo
authors.initials: LW
authors.lastname: Kang
mesh_terms: D019747:Aldose-Ketose Isomerases / Q000737:chemistry* / Q000235:genetics; D001426:Bacterial Proteins / Q000737:chemistry* / Q000235:genetics; D003001:Cloning, Molecular; D048013:Acetivibrio thermocellus / Q000201:enzymology*; D003460:Crystallization; D018360:Crystallography, X-Ray; D008969:Molecular Sequence Data; D015394:Molecular Structure; D011487:Protein Conformation; D013379:Substrate Specificity
chemical_list: D001426:Bacterial Proteins; D019747:Aldose-Ketose Isomerases; C022548:ribosephosphate isomerase