منابع مشابه
Congenital methemoglobinemia methemoglobin reductase deficiency.
Shortly after the first white settlers crossed through the Cumberland Gap into the western foothills of the Appalachians there arose in one kinship several particu larly swarthy offspring characterized by deep bluish skin coloration. These folks — the Blue Fugates — apparently suffered no ill effects of this condition and indeed numerous off-spring were bom some of which also had this peculiar...
متن کاملProperties of methemoglobin reductase and kinetic study of methemoglobin reduction.
A soluble erythrocyte cytochrome b5 was purified as the substrate of methemoglobin reductase and an electron carrier to methemoglobin. The isoelectric point of this protein was at pH 4.3, and E0' was -0.010 at pH 7.0.. The Km value of the enzyme for this protein was 1 x 10(-4) M, and the turnover number (k5) was 3.4 x 10(4) min-1, with NADH as an electron donor at pH 7.0. The optimum pH of the ...
متن کاملMethemoglobin Reductase ( Cytochrome b 5 Reductase ) Deficiency in Congenital
Two NADH diaphorases, diaphorase I and II, were isolated from normal red cells and congenital methemoglobinemic red cells by CM-cellulose and DE 32 column chromatography. For methemoglobinemic sample, activities of diaphorase I and diaphorase II were 80% and less than 5% of those for the normal red cells, respectively. Only diaphorase II showed cytochrome b5 reductase activity. The cytochrome b...
متن کاملStudies on the Oxidation-reduction of Hemoglobin and Methemoglobin
Hemoglobin is oxidized to methemoglobin by products formed during the oxidation of a number of different substances. With some of these substances, both oxygen consumption and hemoglobin oxidation are accelerated by thermolabile constituents of pneumococci; with others of the easily oxidized substances, neither reaction seems to be influenced by the presence of the bacterial substances. The sam...
متن کاملMembrane-bound cytochrome b5 reductase (methemoglobin reductase) in human erythrocytes. Study in normal and methemoglobinemic subjects.
In this study we present evidence that in human erythrocytes NADH-cytochrome b5 reductase (methemoglobin reductase) is not only soluble but also tightly bound to the membrane. The membrane methemoglobin reductase-like activity is unmasked by Triton X-100 treatment, and represents about half of the total activity in the erythrocytes. Like the amphiphilic microsomal-bound cytochrome b5 reductase,...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Journal of Biological Chemistry
سال: 1972
ISSN: 0021-9258
DOI: 10.1016/s0021-9258(19)45737-2