Reaction: 4-coumarate + H2O = 4-hydroxybenzaldehyde + acetate (overall reaction)
(1a) 4-coumarate + H2O = 3-hydroxy-3-(4-hydroxyphenyl)propanoate
(1b) 3-hydroxy-3-(4-hydroxyphenyl)propanoate = 4-hydroxybenzaldehyde + acetate
Glossary: 4-coumarate = (2E)-3-(4-hydroxyphenyl)acrylate = (2E)-3-(4-hydroxyphenyl)prop-2-enoate
Other name(s): 4-hydroxybenzaldehyde synthase; 4HBS
Systematic name: 4-coumarate acetate-lyase (4-hydroxybenzaldehyde-forming)
Comments: The enzyme has been purified from vanilla pods of the orchid Vanilla planifolia. It is highly specific for 4-coumarate. Similar compounds such as cinnamate, caffeate, sinapate and o-coumarate are not substrates.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, CAS registry number:
References:
1. Podstolski, A., Havkin-Frenkel, D., Malinowski, J., Blount, J.W., Kourteva, G. and Dixon, R.A. Unusual 4-hydroxybenzaldehyde synthase activity from tissue cultures of the vanilla orchid Vanilla planifolia. Phytochemistry 61 (2002) 611-620. [PMID: 12423881]