Overexpression, crystallization and preliminary X-ray crystallographic analysis of D-ribose-5-phosphate isomerase from Clostridium thermocellum.
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%.
Jung
Junho
J
Department of Advanced Technology Fusion, Konkuk University, Hwayang-dong, Gwangjin-gu, Seoul, Republic of Korea.
Yeom
Soo Jin
SJ
Kim
Jisun
J
Kim
Jin Kwang
JK
Natarajan
Sampath
S
Ahn
Yeh Jin
YJ
Lim
Sang Boem
SB
Oh
Deok Kun
DK
Kang
Lin Woo
LW
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
D001426:Bacterial Proteins; D019747:Aldose-Ketose Isomerases; C022548:ribosephosphate isomerase