Copper(II)-albumin complex can activate hydrogen peroxide in the presence of biological reductants: first ESR evidence for the formation of hydroxyl radical.
Copper(II)-albumin complex did not directly react with hydrogen peroxide (H2O2). However, Cu(II)-albumin complex was easily reduced to Cu(I) complex by some biological reductants such as L-cysteine and L-ascorbic acid. Cu(I) complex thus formed could react with H2O2 to give hydroxyl radical (.OH) which was detected by electron spin resonance (ESR) spectroscopy using some water-soluble spin-traps. This result gives the first ESR evidence for the formation of OH radical by the reaction of Cu(II)-albumin with H2O2 in the presence of biological reductants.
Division of Chemical Pharmacology, National Institute of Radiological Sciences, Chiba, Japan.
T
T
Ozawa
J
J
Ueda
A
A
Hanaki
D000418:Albumins / Q000378:metabolism*; D001205:Ascorbic Acid / Q000378:metabolism; D002021:Buffers; D003300:Copper / Q000378:metabolism*; D003545:Cysteine / Q000378:metabolism; D004578:Electron Spin Resonance Spectroscopy; D005609:Free Radicals; D006861:Hydrogen Peroxide / Q000378:metabolism*; D006878:Hydroxides / Q000378:metabolism*; D017665:Hydroxyl Radical; D010084:Oxidation-Reduction; D013237:Stereoisomerism
D000418:Albumins; D002021:Buffers; D005609:Free Radicals; D006878:Hydroxides; D017665:Hydroxyl Radical; D003300:Copper; D006861:Hydrogen Peroxide; D003545:Cysteine; D001205:Ascorbic Acid