Phenylpropenal double bond reductases

Monolignol units usually maintain their trans-double bond in the side chain. During heartwood formation in gymnosperms, however, this double bond is reduced by phenylpropenal double bond reductases (PPDBR). The enzyme from Pinus taeda accepted dehydrodiconiferyl and coniferyl aldehydes but not the respective alcohols and NADPH as substrates (Kasahara et at, 2006). The structure of a very similar alkenal double bond reductase from Arabidopsis was studied (Youn et at, 2006b). 

Karam, M.D. (2001) The role of the B/b allelic pair in coumarin biosynthesis in white sweetclover (Melilotus alba Desr.). Flonors Thesis, University of Iowa, USA. Kasahara, FI., Jiao, Y, Bedgar, D.L., Kim, S.J., Patten, A.M., Xia, Z.Q., Davina, L.B. and Lewis, N.G. (2006) Pinus taeda phenylpropenal double-bond reductase ... 

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