Properties of methemoglobin reductase and kinetic study of methemoglobin reduction.
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چکیده
منابع مشابه
Properties 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 ...
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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...
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The regulation of methemoglobin reduction in human erythrocytes was studied in vitro in association with glycolytic reactions, by using hemolysates prepared from the nitrate-treated eryth rocytes. The results obtained are as follows; 1) The addition of cytochrome b5 to the reaction mixture containing fructose 1,6-diphosphate as the substrate for glycolysis caused a marked increase in...
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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...
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ژورنال
عنوان ژورنال: Journal of Biological Chemistry
سال: 1981
ISSN: 0021-9258
DOI: 10.1016/s0021-9258(19)69231-8