| EC |
4.2.1.104 |
| Accepted name: |
cyanase |
| Reaction: |
cyanate + hydrogencarbonate + 2 H+ = NH3 + 2 CO2 (overall reaction)
(1a) cyanate + hydrogencarbonate + H+ = carbamate + CO2
(1b) carbamate + H+ = NH3 + CO2 (spontaneous) |
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For diagram of reaction, click here |
| Glossary: |
cyanate = NCO-
carbamate = H2N-CO-O- |
| Other name(s): |
cyanate lyase; cyanate hydrolase; cyanate aminohydrolase; cyanate C-N-lyase; cyanate hydratase |
| Systematic name: |
carbamate hydro-lyase |
| Comments: |
This enzyme, which is found in bacteria and plants, is used to decompose cyanate, which can be used as the sole source of nitrogen [6,7]. Reaction (1a) can be considered an equivalent of 'cyanate + H2O = carbamate', where the water molecule is provided by the dehydration of bicarbonate to carbon dioxide [2], and hence the enzyme is classified as a hydrolase. |
| Links to other databases: |
BRENDA, EAWAG-BBD, EXPASY, KEGG, MetaCyc, PDB, CAS registry number: 37289-24-0 |
| References: |
| 1. |
Anderson, P.M. Purification and properties of the inducible enzyme cyanase. Biochemistry 19 (1980) 2882–2888. [PMID: 6994799] |
| 2. |
Johnson, W.V. and Anderson, P.M. Bicarbonate is a recycling substrate for cyanase. J. Biol. Chem. 262 (1987) 9021–9025. [PMID: 3110153] |
| 3. |
Taussig, A. The synthesis of the induced enzyme, "cyanase", in E. coli. Biochim. Biophys. Acta 44 (1960) 510–519. [PMID: 13775509] |
| 4. |
Taussig, A. Some properties of the induced enzyme cyanase. Can. J. Biochem. 43 (1965) 1063–1069. [PMID: 5322950] |
| 5. |
Anderson, P.M., Korte, J.J. and Holcomb, T.A. Reaction of the N-terminal methionine residues in cyanase with diethylpyrocarbonate. Biochemistry 33 (1994) 14121–14125. [PMID: 7947823] |
| 6. |
Kozliak, E.I., Fuchs, J.A., Guilloton, M.B. and Anderson, P.M. Role of bicarbonate/CO2 in the inhibition of Escherichia coli growth by cyanate. J. Bacteriol. 177 (1995) 3213–3219. [DOI] [PMID: 7768821] |
| 7. |
Walsh, M.A., Otwinowski, Z., Perrakis, A., Anderson, P.M. and Joachimiak, A. Structure of cyanase reveals that a novel dimeric and decameric arrangement of subunits is required for formation of the enzyme active site. Structure 8 (2000) 505–514. [DOI] [PMID: 10801492] |
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| [EC 4.2.1.104 created 1972 as EC 3.5.5.3, transferred 1990 to EC 4.3.99.1, transferred 2001 to EC 4.2.1.104, modified 2007] |
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