Soluble NADH-cytochrome b5 reductase from rabbit liver cytosol: partial purification and characterization
| Autor: | Jean-Claude Kaplan, Alena Leroux, D. Lostanlen, A. Vieire De Barros |
|---|---|
| Rok vydání: | 1978 |
| Předmět: |
Reductase
Substrate Specificity Electron Transport chemistry.chemical_compound Cytosol Species Specificity Oxidoreductase Methods Animals Humans Polyacrylamide gel electrophoresis Cytochrome b5 reductase Cytochrome Reductases chemistry.chemical_classification Chemistry Substrate (chemistry) General Medicine Hydrogen-Ion Concentration Molecular Weight Potassium ferricyanide Enzyme Isoelectric point Biochemistry Liver Solubility Rabbits |
| Zdroj: | Biochimica et biophysica acta. 526(1) |
| ISSN: | 0006-3002 |
| Popis: | A soluble form of NADH-cytochrome b5 reductase (NADH: ferricytochrome b5 oxidoreductase, EC 1.6.2.2) was found in the cytosolic fraction of rabbit liver. The partially purified enzyme was strictly specific for NADH. It catalyzed the reduction of several substrates such as the methemoglobin-ferrocyanide complex (Hegesh, E. and Avron, M. (1967) Biochim. Biophys. Acta 146, 91-101) (apparent Km: 8 micrometer), potassium ferricyanide (apparent Km: 10 micrometer) and ferricytochrome b5 (apparent Km: 15 micrometer). Upon acrylamide gel isoelectro-focusing followed by specific staining, the enzyme was resolved into four bands (isoelectric pH: 7.05, 6.70, 6.50 and 6.30). The optimum pH of activity with ferricytochrome b5 as a substrate was 6.5. The estimated molecular weight was 25 000--30 000. The enzyme was unsensitive to cyanide. It was strongly inhibited by p-hydroxymercuribenzoate. The cytosolic liver cytochrome b5 reductase was immunologically related to the soluble cytochrome b5 reductase from human and rabbit red-cells, and to the microsomal cytochrome b5 reductase from rabbit liver. |
| Databáze: | OpenAIRE |
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