TY - JOUR
AU - MORITA,, Yuhei
AB - Abstract The instability of human myeloperoxidase [EC 1.11.1.7] compound I, which was spontaneously reduced to compound II, and the abnormal stoichiometry of the reaction of myeloperoxidase with H 2 O 2 were investigated. As to the former, a pretreatment of myeloperoxidase with H 2 O 2 did not stabilize compound I, and no difference in its stability was observed between native (α 2 β 2 ) and hemi (αβ) myeloperoxidase. From these results, it was thought that the instability of compound I was caused by neither the presence of endogenous donors nor the intramolecular reduction of compound I to compound II by the other heme in the native enzyme molecule. As for the latter, true catalase activity of myeloperoxidase was demonstrated by monitoring O 2 evolution after the injection of H 2 O 2 into the enzyme solution. Myeloperoxidase compound I reacted with H 2 O 2 and returned to the ferric state with concomitant evolution of an O2 molecule. Accordingly, the abnormal stoichiometry of the reaction with H 2 O 2 and a part of the instability of compound I can probably be ascribed to this true catalase activity. This content is only available as a PDF. Author notes 1 This study was supported in part by Grant-in-Aid for Scientific Research (No. 61470128) from the Ministry of Education, Science and Culture of Japan. © Oxford University Press
TI -  Reaction of Human Myeloperoxidase with Hydrogen Peroxide and Its True Catalase Activity 
JF - The Journal of Biochemistry
DO - 10.1093/oxfordjournals.jbchem.a122010
DA - 1987-01-01
UR - https://www.deepdyve.com/lp/oxford-university-press/reaction-of-human-myeloperoxidase-with-hydrogen-peroxide-and-its-true-aEcMXXh9mR
SP - 1407
EP - 1412
VL - 101
IS - 6
DP - DeepDyve
ER -