Search results
Results from the WOW.Com Content Network
Cytochrome-b5 reductase is a NADH -dependent enzyme that converts ferricytochrome from a Fe3+ form to a Fe2+ form. [1] It contains FAD and catalyzes the reaction: NADH + H + + 2 ferricytochrome b5 = NAD + + 2 ferrocytochrome b5. In its b5-reducing capacity, this enzyme is involved in desaturation and elongation of fatty acids, cholesterol ...
Methemoglobin. The structure of cytochrome b5 reductase, the enzyme that converts methemoglobin to hemoglobin. [1] Methemoglobin (British: methaemoglobin, shortened MetHb) (pronounced "met-hemoglobin") is a hemoglobin in the form of metalloprotein, in which the iron in the heme group is in the Fe 3+ (ferric) state, not the Fe 2+ (ferrous) of ...
Spontaneously formed methemoglobin is normally reduced (regenerating normal hemoglobin) by protective enzyme systems, e.g., NADH methemoglobin reductase (cytochrome-b5 reductase) (major pathway), NADPH methemoglobin reductase (minor pathway) and to a lesser extent the ascorbic acid and glutathione enzyme systems. Disruptions with these enzyme ...
The methylene blue sulfide test is a convenient method often used in soil microbiology to quickly detect in water the metabolic activity of sulfate reducing bacteria (SRB). It must be noted that in this colorimetric test, methylene blue is a product formed by the reaction and not a reagent added to the system.
In such cases, the enzyme methemoglobin reductase will be able to eventually reactivate methemoglobin by reducing the iron center. In adult humans, the most common hemoglobin type is a tetramer (which contains four subunit proteins) called hemoglobin A , consisting of two α and two β subunits non-covalently bound, each made of 141 and 146 ...
Nucleated red blood cell. A human peripheral blood smear; NRBCs are visible as larger cells with dark centers. A nucleated red blood cell (NRBC), also known by several other names, is a red blood cell that contains a cell nucleus. Almost all vertebrate organisms have hemoglobin -containing cells in their blood, and with the exception of mammals ...
In enzymology, a ferric-chelate reductase (EC 1.16.1.7) is an enzyme that catalyzes the chemical reaction 2 Fe(II) + NAD + ⇌ {\displaystyle \rightleftharpoons } 2 Fe(III) + NADH + H + Thus, the two substrates of this enzyme are Fe(II) and NAD + , whereas its 3 products are Fe(III) , NADH , and H + .
In biochemistry, the Luebering–Rapoport pathway (also called the Luebering–Rapoport shunt) is a metabolic pathway in mature erythrocytes involving the formation of 2,3-bisphosphoglycerate (2,3-BPG), which regulates oxygen release from hemoglobin and delivery to tissues. 2,3-BPG, the reaction product of the Luebering–Rapoport pathway was first described and isolated in 1925 by the ...