Reaction: methylenediurea + 2 H2O = urea + formaldehyde + 2 NH3 + CO2 (overall reaction)
(1a) methylenediurea + H2O = N-(carboxyaminomethyl)urea + NH3
(1b) N-(carboxyaminomethyl)urea = N-(aminomethyl)urea + CO2 (spontaneous)
(1c) N-(aminomethyl)urea + H2O = N-(hydroxymethyl)urea + NH3
(1d) N-(hydroxymethyl)urea = urea + formaldehyde (spontaneous)
Other name(s): methylenediurease
Systematic name: methylenediurea amidohydrolase
Comments: The enzyme acts on several methyleneurea condensates including trimethylenetetraurea, dimethylenetriurea, and methylenediurea. An initial hydrolysis of the terminal amino group is followed by spontaneous decarboxylation, generating a new terminal amino group. A second hydrolysis generates a terminal hydroxymethyl group that leaves in the form of formaldehyde. The enzyme, characterized from the bacteria Brucella anthropi, Cupriavidus pauculus, and Agrobacterium radiobacter, can also act on allantoate, which is hydrolysed to ureidoglycolate, ammonia and carbon dioxide.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, CAS registry number:
References:
1. Jahns, T., Schepp, R., Kaltwasser, H. Purification and characterisation of an enzyme from a strain of Ochrobactrum anthropi that degrades condensation products of urea and formaldehyde (ureaform). Can. J. Microbiol. 43 (1997) 1111-1117.
2. Jahns, T. and Kaltwasser, H. Mechanism of microbial degradation of slow-release fertilizers. J. Polym. Environ. 8 (2000) 11-16.
3. Jahns, T., Ewen, H. and Kaltwasser, H. Biodegradability of urea-aldehyde condensation products. J. Polym. Environ. 11 (2003) 155-159.
4. Koivunen, M.E., Morisseau, C., Newman, J.W., Horwath, W.R. and Hammock, B.D. Purification and characterization of a methylene urea-hydrolyzing enzyme from Rhizobium radiobacter (Agrobacterium tumefaciens). Soil Biol. Biochem. 35 (2003) 1433-1442.
5. Yang, Z., Shi, Y., Sun, Y., Wang, L. and Guan, F. The study on biodegradation of methylene urea by activated sludge. Polym. Degrad. Stab. 128 (2016) 107-114.