METHEMOGLOBIN

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 ...

The Formation of Methemoglobin

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...

Diffusivity Measurements of Human Methemoglobin

Experimental measurements of the diffusion coefficient of human methemoglobin were made at 25 degrees C with a modified Stokes diaphragm diffusion cell. A Millipore filter was used in place of the ordinary fritted disc to facilitate rapid achievement of steady state in the diaphragm. Methemoglobin concentrations varied from approximately 5 g/100 ml to 30 g/100 ml. The diffusion coefficient in t...

Relation of methemoglobin to hemolysis.