Reaction: 2 4-coumaroyl-CoA + malonyl-CoA + H2O = 3 CoA + bisdemethoxycurcumin + 2 CO2
For diagram of reaction click here.
Glossary: bisdemethoxycurcumin = (1E,6E)-5-hydroxy-1,7-bis(4-hydroxyphenyl)hepta-1,4,6-trien-3-one
Other name(s): CUS; curcuminoid synthase (ambiguous)
Systematic name: 4-coumaroyl-CoA:malonyl-CoA 4-coumaryltransferase (bisdemethoxycurcumin-forming)
Comments: A polyketide synthase characterized from the plant Oryza sativa (rice) that catalyses the formation of the C6-C7-C6 diarylheptanoid scaffold of bisdemethoxycurcumin. Unlike the process in the plant Curcuma longa (turmeric), where the conversion is carried out via a diketide intermediate by two different enzymes (EC 22.214.171.124, phenylpropanoyl-diketide CoA synthase and EC 126.96.36.199, curcumin synthase), the diketide intermediate formed by this enzyme remains within the enzyme's cavity and is not released to the environment.
Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number:
1. Morita, H., Wanibuchi, K., Nii, H., Kato, R., Sugio, S. and Abe, I. Structural basis for the one-pot formation of the diarylheptanoid scaffold by curcuminoid synthase from Oryza sativa. Proc. Natl. Acad. Sci. USA 107 (2010) 19778-19783. [PMID: 21041675]