Impairment of tactile and thermal sensitivity in an elderly woman during alpha-IFN treatment

The five enzymes lipoamide dehydrogenase, glutathione reductase, thioredoxin reductase, NADH-cytochrome b5, reductase, and NADPH-cytochrome P-450 reductase are all flavin-containing dehydrogenases that do not contain metals. The terms dehydrogenase and reductase, when applied to these nonmetalloflavoproteins, usually connote electron transferases which, following reduction by their donor substrate, react only slowly with oxygen. They are thus distinguished from the oxidases that react rapidly with oxygen and from the hydroxylases that react more rapidly with oxygen in the presence of their other substrates. NADH-cytochrome b5, reductase and NADPH-cytochrome P-450 reductase are microsomal enzymes. The adrenodoxin reductase and the rubredoxin reductase, together with their respective iron–sulfur protein acceptors, each constitutes a cytochrome P-450 reductase system. Electron transfer between pyridine nucleotides and disulfide compounds is catalyzed by several flavoproteins. Lipoamide dehydrogenase functions in the oxidative decarboxylation of α-keto acids catalyzing the reoxidation of reduced lipoate by NAD+. Glutathione reductase catalyzes electron transfer between NADPH and glutathione. Thioredoxin reductase catalyzes the reduction of thioredoxin by NADPH.