Peroxidase activity of oxyhaemoglobin in vitro.
In bovine erythrocyte suspensions incubated with 16 mM aniline, 4-phenetidine, 4-chloro- or 3,4-dichloroaniline for three hours at 37 degrees C, HbFe3+ concentrations of 10, 35, 77 and 93%, respectively, were found. N- and C-oxygenation products of aniline, 4-chloro-, and 3,4-dichloroaniline were formed, which can explain the oxidation of HbFe3+, indicative of peroxygenase activity of oxyhaemoglobin. The same N- and C-oxygenated derivatives of 4-chloro- and 3,4-dichloroaniline were also formed by hepatic microsomes, although at a 25- to 5000-fold higher rate. HbFe3+ was formed more readily on incubation of either bovine erythrocytes or purified human Hb with various N-arylacetohydroxamic acids. The metabolites of N-(4-chlorophenyl)-N-hydroxyacetamide are the same as the products of chemical oxidation of NOH-4ClAA by PbO2 or KMnO4, indicating the peroxidase activity of oxyhaemoglobin.
D000814:Aniline Compounds / Q000378:metabolism; D000818:Animals; D002417:Cattle; D004912:Erythrocytes / Q000378:metabolism; D006454:Hemoglobins / Q000378:metabolism; D006801:Humans; D006877:Hydroxamic Acids / Q000097:blood; D007700:Kinetics; D008297:Male; D008862:Microsomes, Liver / Q000378:metabolism; D010108:Oxyhemoglobins / Q000378:metabolism*; D010544:Peroxidases / Q000097:blood*; D010628:Phenetidine / Q000378:metabolism; D011817:Rabbits
D000814:Aniline Compounds; D006454:Hemoglobins; D006877:Hydroxamic Acids; D010108:Oxyhemoglobins; D010628:Phenetidine; C014464:3,4-dichloroaniline; D010544:Peroxidases; C023650:aniline; C004658:4-chloroaniline