TY - JOUR
T1 - Structures of mammalian cytosolic quinone reductases
AU - Foster, Christine E.
AU - Bianchet, Mario A.
AU - Talalay, Paul
AU - Faig, Margarita
AU - Amzel, L. Mario
N1 - Funding Information:
This work was supported by Grants GM45540A (to L. M. A.) and 5T32 GM07445 (to C. E. F.) from the National Institutes of Health, and by Grant CA44530 (to P. T.) from the National Cancer Institute, Department of Health and Human Services.
Copyright:
Copyright 2018 Elsevier B.V., All rights reserved.
PY - 2000/8
Y1 - 2000/8
N2 - The metabolism of quinone compounds presents one source of oxidative stress in mammals, as many pathways proceed by mechanisms that generate reactive oxygen species as by-products. One defense against quinone toxicity is the enzyme NAD(P)H:quinone oxidoreductase type 1 (QR1), which metabolizes quinones by a two-electron reduction mechanism, thus averting production of radicals. QR1 is expressed in the cytoplasm of many tissues, and is highly inducible. A closely related homologue, quinone reductase type 2 (QR2), has been identified in several mammalian species. QR2 is also capable of reducing quinones to hydroquinones, but unlike QR1, cannot use NAD(P)H. X-ray crystallographic studies of QR1 and QR2 illustrate that despite their different biochemical properties, these enzymes have very similar three- dimensional structures. In particular, conserved features of the active sites point to the close relationship between these two enzymes. (C) 2000 Elsevier Science Inc.
AB - The metabolism of quinone compounds presents one source of oxidative stress in mammals, as many pathways proceed by mechanisms that generate reactive oxygen species as by-products. One defense against quinone toxicity is the enzyme NAD(P)H:quinone oxidoreductase type 1 (QR1), which metabolizes quinones by a two-electron reduction mechanism, thus averting production of radicals. QR1 is expressed in the cytoplasm of many tissues, and is highly inducible. A closely related homologue, quinone reductase type 2 (QR2), has been identified in several mammalian species. QR2 is also capable of reducing quinones to hydroquinones, but unlike QR1, cannot use NAD(P)H. X-ray crystallographic studies of QR1 and QR2 illustrate that despite their different biochemical properties, these enzymes have very similar three- dimensional structures. In particular, conserved features of the active sites point to the close relationship between these two enzymes. (C) 2000 Elsevier Science Inc.
KW - Flavoprotein
KW - Free radicals
KW - Hydride transfer
KW - Metalloprotein
KW - NAD(P)H:quinone oxidocreductase
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U2 - 10.1016/S0891-5849(00)00299-9
DO - 10.1016/S0891-5849(00)00299-9
M3 - Article
C2 - 11035252
AN - SCOPUS:0033800872
SN - 0891-5849
VL - 29
SP - 241
EP - 245
JO - Free Radical Biology and Medicine
JF - Free Radical Biology and Medicine
IS - 3-4
ER -