Search by BoMiProt ID - Bomi23

Primary Information

BoMiProt ID Bomi23
Protein Name Xanthine dehydrogenase/oxidase
Organism Bos taurus
Uniprot IdP80457
Milk FractionWhey
Ref Sequence Id NP_776397.1
Amino Acid Lenth 1332
Molecular Weight 146790
Fasta Sequence
Gene Name XDH
Gene Id 280960
Protein Existence Status Reviewed: Experimental evidence at protein level

Secondry Information

Presence in other biological fluids/tissue/cells Blood, heart, liver, intestine, endothelial cells and at the luminal surface of rat liver sinusoidal endothelial cells,
Protein Function catalyzes the oxidation of hypoxanthine to xanthine and xanthine to uric acid; source of superoxide ion, hydrogen peroxide, and nitric oxide, which can function as second messengers in the activation of various pathways; may induce mutagenesis, cell proliferation, and tumor progression, but they are also associated with apoptosis and cell differentiation; XOR activity generates free radicals and other oxidant reactive species resulting in either harmful or beneficial outcomes; modulate endothelial function and arteriolar tone; may be cytotoxic
Biochemical Properties Represents more than 8% of the intrinsic protein in MFGM;homodimer; oxidizes in the presence of NAD+ or NADP+ as electron acceptors; bacterial XDHs usually show better catalytic activity and thermal stability than eukaryotic XDHs but both display optimum catalytic activity at nearly neutral pH and relatively low temperatures, and very limit pH-activity range; mammalian enzyme exists in two interconvertible forms, xanthine dehydrogenase and xanthine oxidase; can be interconverted reversibly by sulphide reagents or irreversibly by proteolysis; specificity is low for methylene blue and 2.6-dichlorophenolindophenol, ferricyanide, and many quinones; inactive forms are demolybdo or desulfo; XOR inhibitors are allopurinol, oxypurinol or analogues
Significance in milk Antimicrobial activity; natural antibiotic; encourages breas-feeding in infants; generates hydrogen peroxide
PTMs Bovine XOR is not glycosylated; human XO is N-glycosylated; goat MFGM XO contains sialic acids in O-linked glycosylation
PDB ID 1fiq, 1fo4, 1n5x, 1v97, 1vdv, 3am9, 3amz, 3ax7, 3ax9, 3b9j, 3bdj, 3etr, 3eub, 3nrz, 3ns1, 3nvv, 3nvw, 3nvy, 3nvz, 3sr6, 3una, 3unc, 3uni,
Additional Comments XOR activity is upreglated in ischaemia that increases ROS; XOR production increases in brain meningitis;
Bibliography 1. Hancock, J. T., Salisbury, V., Ovejero-Boglione, M. C., Cherry, R., Hoare, C., Eisenthal, R., and Harrison, R. (2002) Antimicrobial properties of milk: dependence on presence of xanthine oxidase and nitrite. Antimicrob. Agents Chemother. 46, 3308–3310.
2. Wang, C.-H., Zhao, T.-X., Li, M., Zhang, C., and Xing, X.-H. (2016) Characterization of a novel Acinetobacter baumannii xanthine dehydrogenase expressed in Escherichia coli. Biotechnol. Lett. 38, 337–344.
3. Parks, D. A. and Granger, D. N. (1986) Xanthine oxidase: biochemistry, distribution and physiology. Acta Physiol. Scand. Suppl. 548, 87–99.
4. de Jong, J. W., van der Meer, P., Nieukoop, A. S., Huizer, T., Stroeve, R. J., and Bos, E. (1990) Xanthine oxidoreductase activity in perfused hearts of various species, including humans. Circ. Res. 67, 770–773.
5. Corte, E. D. and Stirpe, F. (1972) The regulation of rat liver xanthine oxidase. Involvement of thiol groups in the conversion of the enzyme activity from dehydrogenase (type D) into oxidase (type O) and purification of the enzyme. Biochem. J. 126, 739–745.
6. Bray, R. C. (1975) 6 Molybdenum Iron-Sulfur Flauin Hydroxylases and Related Enzymes. Enzym. 12, 299–419.
7. Gutteridge, S., Tanner, S. J., and Bray, R. C. (1978) Comparison of the molybdenum centres of native and desulpho xanthine oxidase. The nature of the cyanide-labile sulphur atom and the nature of the proton-accepting group. Biochem. J. 175, 887–897.
8. Wahl, R. C. and Rajagopalan, K. V. (1982) Evidence for the inorganic nature of the cyanolyzable sulfur of molybdenum hydroxylases. J. Biol. Chem. 257, 1354–1359.
9.Massey, V., Schopfer, L. M., Nishino, T., and Nishino, T. (1989) Differences in protein structure of xanthine dehydrogenase and xanthine oxidase revealed by reconstitution with flavin active site probes. J. Biol. Chem. 264, 10567–10573.
10. Miyamoto, Y., Akaike, T., Yoshida, M., Goto, S., Horie, H., and Maeda, H. (1996) Potentiation of nitric oxide-mediated vasorelaxation by xanthine oxidase inhibitors. Proc. Soc. Exp. Biol. Med. 211, 366–373.
11. Miyamoto, Y., Akaike, T., Yoshida, M., Goto, S., Horie, H., and Maeda, H. (1996) Potentiation of nitric oxide-mediated vasorelaxation by xanthine oxidase inhibitors. Proc. Soc. Exp. Biol. Med. 211, 366–373