Characterization of the cupin‐type phosphoglucose isomerase from the hyperthermophilic archaeon Thermococcus litoralisa

FEBS Letters

Ito, Sohei¹  Wakagi, Takayoshi¹  Jeong, Jong-Jin¹  Shoun, Hirofumi¹  Jeon, Beong-Sam¹  Fushinobu, Shinya¹ 

[1] Department of Biotechnology, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan

关键词: Phosphoglucose isomerase;    Cupin;    Metal-binding site;    Thermococcus litoralis;    PGI;    phosphoglucose isomerase;    tlPGI;    phosphoglucose isomerase from Thermococcus litoralis;    pfPGI;    phosphoglucose isomerase from Pyrococcus furiosus;    G-6-P;    glucose 6-phosphate;    F-6-P;    fructose 6-phosphate;    ORF;    open reading frame;    ICPAES;    inductively coupled plasma atomic emission spectroscopy;   

DOI  :  10.1016/S0014-5793(02)03900-5

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The gene encoding phosphoglucose isomerase was cloned from Thermococcus litoralis, and functionally expressed in Escherichia coli. The purified enzyme, a homodimer of 21.5 kDa subunits, was biochemically characterized. The inhibition constants for four competitive inhibitors were determined. The enzyme contained 1.25 mol Fe and 0.24 mol Zn per dimer. The activity was enhanced by the addition of Fe²⁺, but inhibited by Zn²⁺ and EDTA. Enzymes with mutations in conserved histidine and glutamate residues in their cupin motifs contained no metals, and showed large decreases in k _cat. The circular dichroism spectra of the mutant enzymes and the wild type enzyme were essentially the same but with slight differences.

【 授权许可】

Unknown