Investigation of the active site of Escherichia coli Cu,Zn superoxide dismutase reveals the absence of the copper-coordinated water molecule.: Is the water molecule really necessary for the enzymatic mechanism?

被引：6

作者：

Sette, M

Bozzi, M

Battistoni, A

Fasano, M

Paci, M

Rotilio, G

机构：

[1] Univ Roma Tor Vergata, Dept Chem Sci & Technol, I-00133 Rome, Italy

[2] Univ Roma Tor Vergata, INFM, I-00133 Rome, Italy

[3] Univ Roma Tor Vergata, Dept Biol, I-00133 Rome, Italy

[4] Univ Turin, IFM, Dept Chem, I-10125 Turin, Italy

[5] Natl Inst Nutr, I-00176 Rome, Italy

来源：

FEBS LETTERS | 2000年 / 483卷 / 01期

关键词：

superoxide dismutase; Cu; Zn superoxide dismutase; water coordination; active site; Escherichia coli;

D O I：

10.1016/S0014-5793(00)02074-3

中图分类号：

Q5 [生物化学]; Q7 [分子生物学];

学科分类号：

071010 ; 081704 ;

摘要：

The active site of the Cu,Zn superoxide dismutase from Escherichia coli in the oxidized Cu(II) state has been studied by nuclear magnetic relaxation dispersion (NMRD), optical and nuclear magnetic resonance spectroscopy. The orientation of some metal ligands is different with respect to all the other Cu,Zn superoxide dismutases. Moreover, NMRD measurements demonstrate the lack of a copper-coordinated water molecule. In spite of these differences the enzymatic activity is still high. Azide also hinds copper with normal affinity and induces modifications in the active site comparable to those previously observed in the eukaryotic enzymes. Our results suggest that, in this enzyme, the copper-coordinated water molecule appears not necessary for the enzymatic reaction. A role for the copper-coordinated water molecule is discussed in the light of recent crystallographic studies. (C) 2000 Federation of European Biochemical Societies. Published by Elsevier Science B.V. All rights reserved.

引用

页码：21 / 26

页数：6

共 32 条

[1] Structural determinants of fluoride and formate binding to hemoglobin and myoglobin: Crystallographic and H-1-NMR relaxometric study [J].