2.0 2012-05-31 13:55:28 -0600 2015-09-17 15:41:13 -0600 ECMDB02078 M2MDB000437 Cyanate The cyanate ion is an anion consisting of one oxygen atom, one carbon atom, and one nitrogen atom, [OCN], in that order. The cyanate ion possesses 1 unit of negative charge, borne mainly by the nitrogen atom. In organic compounds the cyanate group is a functional group.; The cyanate ion is an ambident nucleophile in nucleophilic substitution because it can react to form an alkyl cyanate R-OCN (exception) or an alkyl isocyanate R-NCO (rule). Aryl cyanates (C6H5OCN) can be formed by a reaction of phenol with cyanogen chloride (ClCN) in the presence of a base. The cyanate ion is relatively non-toxic in comparison with cyanides. Use of this fact is made in cyanide decontamination processes where a permanganate oxidation converts toxic cyanide to safer cyanate. Cyanate can be decomposed by the enzyme cyanate lyase (or cyanase), which is found in bacteria and plants. In particular cyanate can be decomposed to carbamate (ammonia) and carbon dioxide. Alternately the same enzyme can be used to synthesize cyanate using carbamate and carbon dioxide. Cyanic acid Hydrogen cyanate Hydrogen cyanic acid CNO 42.0168 41.997988627 cyanic acid cyanic acid 71000-82-3 [O-]C#N InChI=1S/CHNO/c2-1-3/h3H/p-1 XLJMAIOERFSOGZ-UHFFFAOYSA-M Solid Cytosol Extra-organism Periplasm logp -1.08 ALOGPS logs -0.44 ALOGPS solubility 1.55e+01 g/l ALOGPS logp -0.54 ChemAxon pka_strongest_acidic -1.3 ChemAxon pka_strongest_basic -9.9 ChemAxon iupac cyanic acid ChemAxon average_mass 42.0168 ChemAxon mono_mass 41.997988627 ChemAxon smiles [O-]C#N ChemAxon formula CNO ChemAxon inchi InChI=1S/CHNO/c2-1-3/h3H/p-1 ChemAxon inchikey XLJMAIOERFSOGZ-UHFFFAOYSA-M ChemAxon polar_surface_area 44.02 ChemAxon refractivity 9.22 ChemAxon polarizability 3.16 ChemAxon rotatable_bond_count 0 ChemAxon acceptor_count 2 ChemAxon donor_count 1 ChemAxon physiological_charge -1 ChemAxon formal_charge 0 ChemAxon Nitrogen metabolism The biological process of the nitrogen cycle is a complex interplay among many microorganisms catalyzing different reactions, where nitrogen is found in various oxidation states ranging from +5 in nitrate to -3 in ammonia. The ability of fixing atmospheric nitrogen by the nitrogenase enzyme complex is present in restricted prokaryotes (diazotrophs). The other reduction pathways are assimilatory nitrate reduction and dissimilatory nitrate reduction both for conversion to ammonia, and denitrification. Denitrification is a respiration in which nitrate or nitrite is reduced as a terminal electron acceptor under low oxygen or anoxic conditions, producing gaseous nitrogen compounds (N2, NO and N2O) to the atmosphere. Nitrate can be introduced into the cytoplasm through a nitrate:nitrite antiporter NarK or a nitrate / nitrite transporter NarU. Nitrate is then reduced by a Nitrate Reductase resulting in the release of water, an acceptor and a Nitrite. Nitrite can also be introduced into the cytoplasm through a nitrate:nitrite antiporter NarK Nitrite can be reduced a NADPH dependent nitrite reductase resulting in water and NAD and Ammonia. Nitrite can interact with hydrogen ion, ferrocytochrome c through a cytochrome c-552 ferricytochrome resulting in the release of ferricytochrome c, water and ammonia Another process by which ammonia is produced is by a reversible reaction of hydroxylamine with a reduced acceptor through a hydroxylamine reductase resulting in an acceptor, water and ammonia. Water and carbon dioxide react through a carbonate dehydratase resulting in carbamic acid. This compound reacts spontaneously with hydrogen ion resulting in the release of carbon dioxide and ammonia. Carbon dioxide can interact with water through a carbonic anhydrase resulting in hydrogen carbonate. This compound interacts with cyanate and hydrogen ion through a cyanate hydratase resulting in a carbamic acid. Ammonia can be metabolized by reacting with L-glutamine and ATP driven glutamine synthetase resulting in ADP, phosphate and L-glutamine. The latter compound reacts with oxoglutaric acid and hydrogen ion through a NADPH dependent glutamate synthase resulting in the release of NADP and L-glutamic acid. L-glutamic acid reacts with water through a NADP-specific glutamate dehydrogenase resulting in the release of oxoglutaric acid, NADPH, hydrogen ion and ammonia. PW000755 ec00910 Metabolic ABC transporters ec02010 cyanate degradation The cyanate degradation pathway begins with the transportation of cyanate into the cytosol through a cynX transporter. Once inside the cytosol cyanate reacts with hydrogen carbonate and a hydrogen ion through a cyanase resulting in the release of carbon dioxide and carbamate. Carbamate reacts spontaneously with hydrogen resulting in the release of ammonium and carbon dioxide. Carbon dioxide reacts with water through carbonic anhydrase resulting in the release of hydrogen ion and hydrogen carbonate. PW002099 Metabolic cyanate degradation CYANCAT-PWY Specdb::CMs 151844 Specdb::MsMs 29543 Specdb::MsMs 29544 Specdb::MsMs 29545 Specdb::MsMs 36101 Specdb::MsMs 36102 Specdb::MsMs 36103 Specdb::MsMs 1218088 Specdb::MsMs 1218089 Specdb::MsMs 1218090 Specdb::MsMs 2800327 Specdb::MsMs 2800328 Specdb::MsMs 2800329 Specdb::MsMs 2878334 Specdb::MsMs 2878335 Specdb::MsMs 2878336 HMDB02078 540 94771 C01417 29195 CPD-69 Cyanate Keseler, I. M., Collado-Vides, J., Santos-Zavaleta, A., Peralta-Gil, M., Gama-Castro, S., Muniz-Rascado, L., Bonavides-Martinez, C., Paley, S., Krummenacker, M., Altman, T., Kaipa, P., Spaulding, A., Pacheco, J., Latendresse, M., Fulcher, C., Sarker, M., Shearer, A. G., Mackie, A., Paulsen, I., Gunsalus, R. P., Karp, P. D. (2011). "EcoCyc: a comprehensive database of Escherichia coli biology." Nucleic Acids Res 39:D583-D590. 21097882 Kanehisa, M., Goto, S., Sato, Y., Furumichi, M., Tanabe, M. (2012). "KEGG for integration and interpretation of large-scale molecular data sets." Nucleic Acids Res 40:D109-D114. 22080510 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 Hseu, Tzong Hsiung; Lan, Shih Li; Yang, Min Der. Cyanate from alkaline hydrolysis of cyanogen bromide-activated polysaccharides. Analytical Biochemistry (1981), 116(1), 181-4. http://hmdb.ca/system/metabolites/msds/000/001/661/original/HMDB02078.pdf?1358461679 Cyanate hydratase P00816 CYNS_ECOLI cynS http://ecmdb.ca/proteins/P00816.xml Outer membrane protein N P77747 OMPN_ECOLI ompN http://ecmdb.ca/proteins/P77747.xml Outer membrane pore protein E P02932 PHOE_ECOLI phoE http://ecmdb.ca/proteins/P02932.xml Outer membrane protein F P02931 OMPF_ECOLI ompF http://ecmdb.ca/proteins/P02931.xml Cyanate transport protein cynX P17583 CYNX_ECOLI cynX http://ecmdb.ca/proteins/P17583.xml Outer membrane protein C P06996 OMPC_ECOLI ompC http://ecmdb.ca/proteins/P06996.xml Cyanate + 3 Hydrogen ion + Hydrogen carbonate >2 Carbon dioxide + Ammonium Cyanate + Hydrogen ion + Hydrogen carbonate <> Carbon dioxide + Carbamic acid R03546 R524-RXN Cyanate + Hydrogen carbonate + Hydrogen ion > Carbamic acid + Carbon dioxide R524-RXN Cyanate + Carbonic acid + 2 Hydrogen ion > Ammonia +2 Carbon dioxide Cyanate + Hydrogen carbonate + 2 Hydrogen ion + Carbamic acid <> Ammonia +2 Carbon dioxide R10079 Hydrogen carbonate + Cyanate + Hydrogen ion + Cyanate > Carbamic acid PW_R002431 Cyanate + Hydrogen ion + Hydrogen carbonate <> Carbon dioxide + Carbamic acid Cyanate + Hydrogen ion + Hydrogen carbonate <> Carbon dioxide + Carbamic acid