title: Human cytochrome b5 reductase: structure, function, and potential applications.
abstract: Cytochrome b5 reductase is a flavoprotein that is produced as two different isoforms that have different localizations. The amphipathic microsomal isoform, found in all cell types with the exception of erythrocytes, consists of one hydrophobic membrane-anchoring domain and a larger hydrophilic flavin catalytic domain. The soluble cytochrome b5 reductase isoform, found in human erythrocytes, is a truncated protein that is encoded by an alternative transcript and consists of the larger domain only. Cytochrome b5 reductase is involved in the transfer of reducing equivalents from the physiological electron donor, NADH, via an FAD domain to the small molecules of cytochrome b5. This protein has received much attention from researchers due to its involvement in many oxidation and reduction reactions, such as the reduction of methemoglobin to hemoglobin. Autosomal cytochrome b5 reductase gene deficiency manifests with the accumulation of oxidized Fe+3 and recessive congenital methemoglobinemia in humans. In this article, we provide a comprehensive overview of the structure and function of cytochrome b5 reductase from different eukaryotic sources and its potential use in the food industry, biosensor, and diagnostic areas.
authors.affiliation: Department of Pharmaceutical Biotechnology, School of Pharmacy, Zanjan University of Medical Sciences , Iran and.
authors.forename: Fatemeh
authors.initials: F
authors.lastname: Elahian
authors.forename: Zargham
authors.initials: Z
authors.lastname: Sepehrizadeh
authors.forename: Bahareh
authors.initials: B
authors.lastname: Moghimi
authors.forename: Seyed Abbas
authors.initials: SA
authors.lastname: Mirzaei
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D042966:Cytochrome-B(5) Reductase; D005182:Flavin-Adenine Dinucleotide / Q000737:chemistry / Q000378:metabolism; D006801:Humans; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009243:NAD / Q000737:chemistry / Q000378:metabolism; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D016415:Sequence Alignment
chemical_list: D009243:NAD; D005182:Flavin-Adenine Dinucleotide; D042966:Cytochrome-B(5) Reductase
keywords: FAD domain; FNR family; NADH domain; RCM; heterologous expression; mechanism of action; phylogenetics; purification