Copper salt-dependent hydroxyl radical formation. Damage to proteins acting as antioxidants.
Cupric ions (Cu2+) and ferric ions (Fe3+) added to hydrogen peroxide generate hydroxyl radicals (OH) capable of degrading deoxyribose with the formation of thiobarbituric acid-reactive products. This damage can be inhibited by catalase, OH radical scavengers and specific metal ion chelators. All proteins tested nonspecifically inhibited copper-dependent damage but have little effect on the iron-dependent reaction. Copper ions appear to bind to the proteins which prevents formation of OH radicals in free solution. However, OH radicals are still generated at a site-specific location on the protein molecule. Protein damage is detected as fluorescent changes in amino acid residues.
D000418:Albumins / Q000378:metabolism; D000818:Animals; D000975:Antioxidants / Q000378:metabolism*; D002417:Cattle; D003300:Copper / Q000378:metabolism*; D003855:Deoxyribose / Q000378:metabolism; D005290:Ferric Compounds / Q000378:metabolism; D006801:Humans; D006861:Hydrogen Peroxide / Q000378:metabolism; D010206:Papain / Q000378:metabolism; D011506:Proteins / Q000378:metabolism*; D011817:Rabbits; D005719:gamma-Globulins / Q000378:metabolism
D000418:Albumins; D000975:Antioxidants; D005290:Ferric Compounds; D011506:Proteins; D005719:gamma-Globulins; D003855:Deoxyribose; D003300:Copper; D006861:Hydrogen Peroxide; D010206:Papain