Open AccessOverexpression, crystallization and preliminary X‐ray crystallographic analysis of d ‐ribose‐5‐phosphate isomerase from Clostridium thermocellum
Author(s) -
Jung Junho,
Yeom SooJin,
Kim Jisun,
Kim JinKwang,
Natarajan Sampath,
Ahn YehJin,
Lim Sang Boem,
Oh DeokKun,
Kang LinWoo
Publication year - 2009
Publication title -
acta crystallographica section f
Language(s) - English
Resource type - Journals
ISSN - 1744-3091
DOI - 10.1107/s1744309109038093
Subject(s) - isomerase , clostridium thermocellum , chemistry , substrate (aquarium) , stereochemistry , triosephosphate isomerase , aldose , ketose , biochemistry , dimer , enzyme , crystallography , organic chemistry , biology , cellulase , ecology , glycoside
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 P 3 2 21, with unit‐cell parameters a = b = 69.5, c = 154.4 Å, and diffracted to 1.9 Å resolution. According to Matthews coefficient calculations, the crystallographic structure consists of a dimer in the asymmetric unit, with a V M of 3.2 Å 3 Da −1 and a solvent content of 61.7%.