Characterization of the purified NADH-cytochrome b5 reductase of human erythrocytes as a FAD-containing enzyme.

摘要: NADH-cytochrome b5 reductase of normal human erythrocytes was purified by procedures including affinity chromatography on Blue-Sepharose to an electrophoretically homogeneous protein. The enzyme judged be a typical flavoprotein based its absorption spectrum (absorption maxima, 272, 390, and 462 nm; shoulders, 373 488 nm) flavin content (1 mol FAD/mol enzyme). minimum molecular weight calculated from the 32,300. showed distinct negative circular dichroic at 280 nm also 460 480 nm. With best preparations, molar ellipticities were well correlated with activity in enzyme. A partial loss led concomitant decrease Flavin analogues such as acrinol proflavine (0.1 mM) strongly inhibited activity, atebrin inhibition. Complete inhibition observed 1 mM any these reagents. These results apparently indicate that FAD functions prosthetic group, spectroscopy is good measure bound form