2.0 2012-08-09 09:16:17 -0600 2015-06-03 17:21:31 -0600 ECMDB21449 M2MDB001844 Selenophosphate Selenophosphate is the universal selenium donor that is required for the formation of selenium dependent enzymes and selenium tRNAs (i.e.: selenocysteyl-tRNA). Selenophosphate is also the selenium donor used to synthesize selenocysteine, which is co-translationally incorporated into selenoproteins at in-frame UGA codons. Selenophosphate synthetase (EC 2.7.9.3, SPS, product of the E. coli selD gene) produces monoselenophosphate from selenide and ATP. (PMID: 8986768, 10609888) Dihydroxy-oxido-selanylidenephosphorane Phosphorus monoselenide Phosphorus selenide (PSe) Selenidophosphonate Selenidophosphonic acid Selenophosphoric acid Selenoxo-phosphino SePO3 SePO₃ H2O3PSe 159.95 160.89067727 hydroxy(selanylidene)phosphonous acid selenophosphoric acid 289702-60-9 OP(O)([O-])=[Se] InChI=1S/H3O3PSe/c1-4(2,3)5/h(H3,1,2,3,5)/p-1 JRPHGDYSKGJTKZ-UHFFFAOYSA-M Solid logp -1.1 ChemAxon pka_strongest_acidic -6.3 ChemAxon iupac hydroxy(selanylidene)phosphonous acid ChemAxon average_mass 159.95 ChemAxon mono_mass 160.89067727 ChemAxon smiles OP(O)([O-])=[Se] ChemAxon formula H2O3PSe ChemAxon inchi InChI=1S/H3O3PSe/c1-4(2,3)5/h(H3,1,2,3,5)/p-1 ChemAxon inchikey JRPHGDYSKGJTKZ-UHFFFAOYSA-M ChemAxon polar_surface_area 60.69 ChemAxon refractivity 26.32 ChemAxon polarizability 7.23 ChemAxon rotatable_bond_count 0 ChemAxon acceptor_count 4 ChemAxon donor_count 3 ChemAxon physiological_charge -3 ChemAxon formal_charge 0 ChemAxon Selenium metabolism The selenium metabolism begins with the introduction of selenate and selenite to the cytosol through a sulphate permease system. Once in the cell, selenate can be reduced to selenite through nitrate reductases A and Z. Selenite then interacts with glutathione and 2 hydrogen ions resulting in the release of 2 water molecules, a hydroxide molecule, a glutathione disulfide and a selenodiglutathione. The latter compound then reacts with NADPH+H resulting in the release of a NADP, a glutathione and a glutathioselenol. Glutathiolselenol can then be oxidize resulting in a a glutathiolselenol ion which can then interact with a water molecule resulting in a release of glutathion and selenium Glutathiolselenol can also react with NADPH and hydrogen ion resulting in a release of glutathione, NADP, a hydroxide molecule and a hydrogen selenide. This compound can react in a reversible reaction by being oxidized resulting in a hydrogen selenide ion . This compound can then be phosphorylated by interacting with an ATP and releasing a AMP, a phosphate and a selenophosphate. PW001894 Metabolic Specdb::CMs 15002 Specdb::CMs 136167 Specdb::CMs 143901 Specdb::MsMs 29927 Specdb::MsMs 29928 Specdb::MsMs 29929 Specdb::MsMs 2971608 Specdb::MsMs 2971609 Specdb::MsMs 2971610 Specdb::MsMs 23129 Specdb::MsMs 23130 Specdb::MsMs 23131 Specdb::MsMs 2733900 Specdb::MsMs 2733901 Specdb::MsMs 2733902 HMDB06407 1092 7822178 C05172 16144 SEPO3 van der Werf, M. J., Overkamp, K. M., Muilwijk, B., Coulier, L., Hankemeier, T. (2007). "Microbial metabolomics: toward a platform with full metabolome coverage." Anal Biochem 370:17-25. 17765195 Winder, C. L., Dunn, W. B., Schuler, S., Broadhurst, D., Jarvis, R., Stephens, G. M., Goodacre, R. (2008). "Global metabolic profiling of Escherichia coli cultures: an evaluation of methods for quenching and extraction of intracellular metabolites." Anal Chem 80:2939-2948. 18331064 Guimaraes, M. J., Peterson, D., Vicari, A., Cocks, B. G., Copeland, N. G., Gilbert, D. J., Jenkins, N. A., Ferrick, D. A., Kastelein, R. A., Bazan, J. F., Zlotnik, A. (1996). "Identification of a novel selD homolog from eukaryotes, bacteria, and archaea: is there an autoregulatory mechanism in selenocysteine metabolism?" Proc Natl Acad Sci U S A 93:15086-15091. 8986768 Lacourciere GM: Biosynthesis of selenophosphate. Biofactors. 1999;10(2-3):237-44. 10609888 Chung HJ, Yoon SI, Shin SH, Koh YA, Lee SJ, Lee YS, Bae S: p53-Mediated enhancement of radiosensitivity by selenophosphate synthetase 1 overexpression. J Cell Physiol. 2006 Oct;209(1):131-41. 16786570 tRNA 2-selenouridine synthase P33667 SELU_ECOLI selU http://ecmdb.ca/proteins/P33667.xml tRNA containing 5-methylaminomethyl-2-thiouridylate + Selenophosphate > unknown + tRNA containing 5-methylaminomethyl-2-selenouridine RXN0-2281 Water + Selenium + Adenosine triphosphate > Phosphate + Selenophosphate + Adenosine monophosphate 2.7.9.3-RXN