Cytochrome b5, type A

Cytochrome b5 type A (microsomal)

PDB rendering based on 1cyo.

Available structures
PDB	1cyo, 1do9, 1ehb, 1es1, 1f03, 1f04, 1i5u, 1j0q, 1lqx, 1lr6, 1m20, 1m2i, 1m2m, 1m59, 1nx7, 1sh4, 1u9m, 1u9u

Identifiers

Symbols

CYB5A; CYB5; MCB5

External IDs

OMIM: 613218 MGI: 1926952 HomoloGene: 41475 GeneCards: CYB5A Gene

Gene Ontology
Molecular function	• aldo-keto reductase (NADP) activity • cytochrome-c oxidase activity • enzyme binding • heme binding • metal ion binding
Cellular component	• cytoplasm • mitochondrion • mitochondrial outer membrane • mitochondrial outer membrane • endoplasmic reticulum • endoplasmic reticulum membrane • microsome • membrane • integral to membrane
Biological process	• vitamin metabolic process • water-soluble vitamin metabolic process • transport • electron transport chain
Sources: Amigo / QuickGO

RNA expression pattern

More reference expression data

Orthologs

Species

Human

Mouse

RefSeq (mRNA)

RefSeq (protein)

Location (UCSC)

Chr 18:
71.92 – 71.96 Mb

Chr 18:
85.02 – 85.05 Mb

PubMed search

[1]

[2]

Cytochrome b5, form A (gene name CYB5A), is a human microsomal cytochrome b5.^[1]

Cytochrome b5 is a membrane bound hemoprotein which function as an electron carrier for several membrane bound oxygenases. It has two isoforms produced by alternative splicing. Isoform 1 is bound to the cytoplasmic side of the endoplasmic reticulum. It has a C-terminal transmembrane alpha-helix. Isoform 2 was found in cytoplasm. Defects in CYB5A are the cause of type IV hereditary methemoglobinemia.

References

^ "Entrez Gene: CYB5A Cytochrome b5, form A". http://www.ncbi.nlm.nih.gov/sites/entrez?Db=gene&Cmd=ShowDetailView&TermToSearch=1528.

Ng S, Smith MB, Smith HT, Millett F (1977). "Effect of modification of individual cytochrome c lysines on the reaction with cytochrome b5.". Biochemistry 16 (23): 4975–8. doi:10.1021/bi00642a006. PMID 199233.
Dailey HA, Strittmatter P (1979). "Modification and identification of cytochrome b5 carboxyl groups involved in protein-protein interaction with cytochrome b5 reductase.". J. Biol. Chem. 254 (12): 5388–96. PMID 221468.
Mitoma J, Ito A (1992). "The carboxy-terminal 10 amino acid residues of cytochrome b5 are necessary for its targeting to the endoplasmic reticulum.". EMBO J. 11 (11): 4197–203. PMC 556930. PMID 1396600. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=556930.
Giordano SJ, Steggles AW (1991). "The human liver and reticulocyte cytochrome b5 mRNAs are products from a single gene.". Biochem. Biophys. Res. Commun. 178 (1): 38–44. doi:10.1016/0006-291X(91)91776-9. PMID 1712589.
Shephard EA, Povey S, Spurr NK, Phillips IR (1992). "Chromosomal localization of a cytochrome b5 gene to human chromosome 18 and a cytochrome b5 pseudogene to the X chromosome.". Genomics 11 (2): 302–8. doi:10.1016/0888-7543(91)90136-3. PMID 1840560.
Strittmatter P, Hackett CS, Korza G, Ozols J (1991). "Characterization of the covalent cross-links of the active sites of amidinated cytochrome b5 and NADH:cytochrome b5 reductase.". J. Biol. Chem. 265 (35): 21709–13. PMID 2123873.
Ozols J (1989). "Structure of cytochrome b5 and its topology in the microsomal membrane.". Biochim. Biophys. Acta 997 (1-2): 121–30. doi:10.1016/0167-4838(89)90143-X. PMID 2752049.
Yoo M, Steggles AW (1988). "The complete nucleotide sequence of human liver cytochrome b5 mRNA.". Biochem. Biophys. Res. Commun. 156 (1): 576–80. doi:10.1016/S0006-291X(88)80881-7. PMID 3178851.
Hegesh E, Hegesh J, Kaftory A (1986). "Congenital methemoglobinemia with a deficiency of cytochrome b5.". N. Engl. J. Med. 314 (12): 757–61. doi:10.1056/NEJM198603203141206. PMID 3951505.
Abe K, Kimura S, Kizawa R, et al. (1985). "Amino acid sequences of cytochrome b5 from human, porcine, and bovine erythrocytes and comparison with liver microsomal cytochrome b5.". J. Biochem. 97 (6): 1659–68. PMID 4030743.
Strittmatter P, Spatz L, Corcoran D, et al. (1975). "Purification and properties of rat liver microsomal stearyl coenzyme A desaturase.". Proc. Natl. Acad. Sci. U.S.A. 71 (11): 4565–9. doi:10.1073/pnas.71.11.4565. PMC 433928. PMID 4373719. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=433928.
Rashid MA, Hagihara B, Kobayashi M, et al. (1974). "Structural studies of cytochrome b5. 3. Sequential studies on human liver cytochrome b5.". J. Biochem. 74 (5): 985–1002. PMID 4770377.
Nóbrega FG, Ozols J (1971). "Amino acid sequences of tryptic peptides of cytochromes b5 from microsomes of human, monkey, porcine, and chicken liver.". J. Biol. Chem. 246 (6): 1706–17. PMID 4993957.
Ozols J (1972). "Cytochrome b 5 from a normal human liver. Isolation and the partial amino acid sequence.". J. Biol. Chem. 247 (7): 2242–5. PMID 5062820.
Dailey HA, Strittmatter P (1980). "Characterization of the interaction of amphipathic cytochrome b5 with stearyl coenzyme A desaturase and NADPH:cytochrome P-450 reductase.". J. Biol. Chem. 255 (11): 5184–9. PMID 6102994.
De Silvestris M, D'Arrigo A, Borgese N (1995). "The targeting information of the mitochondrial outer membrane isoform of cytochrome b5 is contained within the carboxyl-terminal region.". FEBS Lett. 370 (1-2): 69–74. doi:10.1016/0014-5793(95)00797-D. PMID 7649306.
Li XR, Giordano SJ, Yoo M, Steggles AW (1995). "The isolation and characterization of the human cytochrome b5 gene.". Biochem. Biophys. Res. Commun. 209 (3): 894–900. doi:10.1006/bbrc.1995.1582. PMID 7733981.
Giordano SJ, Yoo M, Ward DC, et al. (1994). "The human cytochrome b5 gene and two of its pseudogenes are located on chromosomes 18q23, 14q31-32.1 and 20p11.2, respectively.". Hum. Genet. 92 (6): 615–8. doi:10.1007/BF00420948. PMID 8262522.
Guengerich FP, Johnson WW (1998). "Kinetics of ferric cytochrome P450 reduction by NADPH-cytochrome P450 reductase: rapid reduction in the absence of substrate and variations among cytochrome P450 systems.". Biochemistry 36 (48): 14741–50. doi:10.1021/bi9719399. PMID 9398194.
Lee-Robichaud P, Akhtar ME, Akhtar M (1998). "Control of androgen biosynthesis in the human through the interaction of Arg347 and Arg358 of CYP17 with cytochrome b5.". Biochem. J.. 332 ( Pt 2): 293–6. PMC 1219480. PMID 9601054. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1219480.

PDB gallery

1cyo: BOVINE CYTOCHROME B(5)

1do9: SOLUTION STRUCTURE OF OXIDIZED MICROSOMAL RABBIT CYTOCHROME B5. FACTORS DETERMINING THE HETEROGENEOUS BINDING OF THE HEME.

1ehb: CRYSTAL STRUCTURE OF RECOMBINANT TRYPSIN-SOLUBILIZED FRAGMENT OF CYTOCHROME B5

1es1: CRYSTAL STRUCTURE OF VAL61HIS MUTANT OF TRYPSIN-SOLUBILIZED FRAGMENT OF CYTOCHROME B5

1f03: SOLUTION STRUCTURE OF OXIDIZED BOVINE MICROSOMAL CYTOCHROME B5 MUTANT (E44A, E48A, E56A, D60A) AND ITS INTERACTION WITH CYTOCHROME C

1f04: SOLUTION STRUCTURE OF OXIDIZED BOVINE MICROSOMAL CYTOCHROME B5 MUTANT (E44A, E48A, E56A, D60A) AND ITS INTERACTION WITH CYTOCHROME C

1i5u: SOLUTION STRUCTURE OF CYTOCHROME B5 TRIPLE MUTANT (E48A/E56A/D60A)

1j0q: Solution Structure of Oxidized Bovine Microsomal Cytochrome b5 mutant V61H

1lqx: Crystal structure of V45E mutant of cytochrome b5

1lr6: Crystal structure of V45Y mutant of cytochrome b5

1m20: Crystal Structure of F35Y Mutant of Trypsin-solubilized Fragment of Cytochrome b5

1m2i: Crystal structure of E44A/E56A mutant of cytochrome b5

1m2m: Crystal structure of E44A/E48A/E56A/D60A mutant of cytochrome b5

1m59: Crystal Structure of P40V Mutant of Trypsin-solubilized Fragment of Cytochrome b5

1nx7: Solution Structure of Oxidized Bovine Microsomal Cytochrome B5

1sh4: Solution structure of oxidized bovine microsomal cytochrome B5 Mutant V45H

1u9m: Crystal structure of F58W mutant of cytochrome b5

1u9u: Crystal structure of F58Y mutant of cytochrome b5

Cytochrome b5, type A

References

Further reading