Cytochrome b5

Cytochromes b5 are ubiquitous electron transport hemoproteins found in animals, plants, fungi and purple phototrophic bacteria. The microsomal and mitochondrial variants are membrane-bound, while bacterial and those from erythrocytes and other animal tissues are water-soluble. The family of cytochrome b5-like proteins includes hemoprotein domains covalently associated with other redox domains in flavocytochrome cytochrome b2, sulfite oxidase, plant and fungal nitrate reductases, and plant and fungal cytochrome b5/acyl lipid desaturase fusion proteins.

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