Differential loss of enzyme activity by vitC and iron containing proteins.
Our earlier studies showed that rabbit muscle phosphoglucomutase was irreversibly inactivated by exposure to a mixture of vitamin C, FeCl3 and O2. The enzyme lost about 70% of its phosphate (V.V. Desphande and J.G. Joshi, J. Biol. Chem. 260, 754-764, 1985). The present report shows that several other iron proteins can substitute for FeCl3 to a varying degree. The rate of inactivation by FeCl3 greater than ferritin greater than hemoglobin = hemerythrin greater than transferrin = ferridoxin = vitamin C. These iron compounds also produced dephosphoenzyme but did not dephosphorylate ATP, ADP, AMP or phospholipids.
D000818:Animals; D001059:Apoproteins / Q000494:pharmacology*; D001205:Ascorbic Acid / Q000494:pharmacology*; D002712:Chlorides; D005288:Ferredoxins / Q000494:pharmacology*; D005290:Ferric Compounds / Q000494:pharmacology; D005293:Ferritins / Q000494:pharmacology*; D006422:Hemerythrin / Q000494:pharmacology*; D006454:Hemoglobins / Q000494:pharmacology*; D006801:Humans; D007501:Iron; D007700:Kinetics; D008667:Metalloproteins / Q000494:pharmacology*; D009132:Muscles / Q000187:drug effects; D010733:Phosphoglucomutase / Q000037:antagonists & inhibitors*; D010743:Phospholipids / Q000494:pharmacology; D011817:Rabbits; D014168:Transferrin / Q000494:pharmacology*
D001059:Apoproteins; D002712:Chlorides; D005288:Ferredoxins; D005290:Ferric Compounds; D006422:Hemerythrin; D006454:Hemoglobins; D008667:Metalloproteins; D010743:Phospholipids; D014168:Transferrin; C028284:apotransferrin; D005293:Ferritins; D007501:Iron; D010733:Phosphoglucomutase; D001205:Ascorbic Acid; C024555:ferric chloride