Reaction: (1) melamine + H2O = ammeline + NH3
(2) ammeline + H2O = ammelide + NH3
Glossary: melamine = 2,4,6-triamino-1,3,5-triazine
ammeline = 4,6-diamino-1,3,5-triazin-2-ol
ammelide = 6-amino-1,3,5-triazine-2,4-diol
Other name(s): triA (gene name)
Systematic name: melamine aminohydrolase
Comments: The enzyme, isolated from the bacterium Acidovorax citrulli, performs the deamination of melamine 15-fold faster than the deamination of ammeline. It also has activity with 2-chloro-4,6-diamino-s-triazine, but has no activity toward halo-substituted triazine ring compounds such as atrazine (cf. EC 3.8.1.8, atrazine chlorohydrolase).
BRENDA, EXPASY, KEGG, MetaCyc, CAS registry number:
References:
1. Seffernick, J.L., Souza, M.L., Sadowsky, M.J. and Wackett, L.P. Melamine deaminase and atrazine chlorohydrolase: 98 percent identical but functionally different. J. Bacteriol. 183 (2001) 2405-2410. [PMID: 11274097]