Cinnamyl alcohol dehydrogenase

Lapierre, C. Pollet, B. Petit-Conil, M. Toval, G. Romero, J. Pilate, G. Leple, J. C. Boerjan, W. Ferret, V. De Nadai, V. Jouanin, L. Stmctural alterations of lignins in transgenic poplars with depressed cinnamyl alcohol dehydrogenase or caffeic acid... 

Lapierre, C. Pollet, B. MacKay, J. J. Sederoff, R. R. Lignin structure in a mutant pine deficient in cinnamyl alcohol dehydrogenase. J. Agric. Food Chem. 2000, 48, 2326-2331. 

Developing stem of tomato and popular Lignification and cinnamyl alcohol dehydrogenase Roth et al. (19)... 

Roth R, Boudet AM, Pont-Lezica R. Lignification and cinnamyl alcohol dehydrogenase activity in developing stems of tomato and popular a spatial and kinetic study through tissue printing. J Exp Bot 1997 48 247-254. 

Pillonel, C., Mulder, M. M., Boon, J. J., Forster, B., and Binder, A., 1991, Involvement of cinnamyl-alcohol dehydrogenase in the control of lignin formation in Sorghum bicolor L. Moench, Planta 185 538-544. 

Ralph, J., Hatfield, R. D., Piquemal, J., Yahiaoui, N., Pean, M., Lapierre, C., Boudet, A. M., 1998, NMR characterization of altered lignins extracted from tobacco plants down-regulated for lignification enzymes cinnamyl alcohol dehydrogenase and cinnamyl-CoA reductase, Proc. Natl. Acad. Sci. USA 95 12803-12808. 

Figure 3-9. Biosynthesis of monolignols. The enzymes involved in this pathway are ( ) hydroxycinnamoyl-CoA shikimate/quinate hydroxy-cinnamoyl transferase, (b) p-coumaroyl-CoA 3 -hydroxylase (E.C. 1.14.14.1), (c) caffeoyl-CoA O-methy 1 Iranslerasc (E.C. 2.1.1.104), (d) cinnamoyl-CoA reductase (E.C. 1.2.1.44) (e) cinnamyl alcohol dehydrogenase (E.C. 1.1.1.195), (f) coniferyl aldehyde/coniferyl alcohol 5-hydroxylase (E.C. 1.14.13), (g) coniferaldehyde/coniferyl alcohol O-methyltransferase (E.C. 2.1.1.68).

Coniferaldehyde (3.76) can undergo several fates, some of which can ultimately lead to the same end product. It can be reduced to coniferyl alcohol (3.79) by the enzyme cinnamyl alcohol dehydrogenase (CAD). Alternatively, the enzyme coniferyl aldehyde/coniferyl alcohol 5-hydroxylase (C5H), also known by its less accurate name ferulic acid 5-hydroxylase (F5H Humphreys et al., 1999) can catalyze the hydroxylation of C5 to result in 5-hydroxyconiferyl aldehyde (3.77). C5H is also able to form 5-hydroxyconiferyl alcohol (3.80) from coniferyl alcohol (3.79). This enzyme was initially identified as F5H, after analysis of the Arabidopsis ferulic acid hydroxylase 1 (fahl) mutant, which was isolated in a mutant screen based on reduced levels of the UV-fluorescent sinapoyl esters (Section 13 Chappie et al., 1992). The FAH1 gene was cloned using a T-DNA tagged mutant allele (Meyer et al., 1996), which revealed that the... 

Halpin, C., Holt, K., Chojecki, J., Oliver, D., Chabbert, B., Monties, B., Edwards, K., Barakate, A., and Foxon, G. A., 1998, Brown-midrib maize (bml) - a mutation affecting the cinnamyl alcohol dehydrogenase gene, Plant J. 14 545-553. 

Sibout, R., Eudes, A., Pollet, B., Goujon, T., Mila, I., Granier, F., Seguin, A., Lapierre, C., and Jouanin, L., 2003, Expression pattern of two paralogs encoding cinnamyl alcohol dehydrogenases in Arabidopsis. Isolation and characterization of the corresponding mutants, Plant Physiol. 132 848-860. 

Tobias, C. M, and Chow, E. K., 2005, Structure of the cinnamyl-alcohol dehydrogenase gene family in rice and promoter activity of a member associated with lignification, Planta 220 678-688. 

O Connell, A., Holt, K., Piquemal, J., Grima-Pettenati, J., Boudet, A., Pollet, B., Lapierre, C., Petit-Conil, M., Schuch, W., and Halpin, C. 2002, Improved paper pulp from plants with suppressed cinnamoyl-CoA reductase or cinnamyl alcohol dehydrogenase, Transgen. Res. 11 495-503. 

Mitchell, H.J., Hall, J.L., and Barber, M S., 1994, Elicitor-induced cinnamyl alcohol dehydrogenase activity in lignifying wheat (Triticum aestivum L.) leaves, Plant Physiol. 104 551-556. 

In this chapter I will focus on biochemical and molecular aspects leading to lignin production. We have studied in detail phenylalanine ammonia lyase (PAL EC 4.3.1.5), the first enzyme of the general phenylpropanoid pathway, and cinnamyl alcohol dehydrogenase (CAD EC 1.1.1.195), an enzyme specific to the branch pathway leading to lignin formation. 

One aspect shared with several other genes of the phenylpropanoid pathway is the transient induction after environmental challenge. This has also been demonstrated for chalcone synthase (Ryder et al., 1984) and chalcone isomerase (Cramer et al., 1985 Mehdy Lamb, 1987), enzymes involved in phytoalexin production, and for cinnamyl alcohol dehydrogenase (CAD) an enzyme of lignin biosynthesis, in response to elicitor treatment of bean tissue culture cells (Grand et al., 1987). 

Grand, C., Sami, F. Lamb, C.J. (1987). Rapid induction by fungal elicitor of the synthesis of cinnamyl-alcohol dehydrogenase, a specific enzyme of lignin synthesis. European Journal of Biochemistry 169, 73-7. 

Walter, M.H., Grima-Pettenati, J., Grand, C., Boudet, A.M. Lamb, C.J. (1988). Cinnamyl alcohol dehydrogenase, a molecular marker specific for lignin synthesis cDNA cloning and mRNA induction by fungal elicitor. Proceedings of the National Academy of Sciences (USA) 86, 5546-50. 

Figure 4.7 Monolignol biosynthesis. Enzymes involved are cinnamoyl-CoAiNADPH oxidoreductase (CCR (1)), cinnamyl alcohol dehydrogenase (CAD (2)), UDP-glucose cinnamyl alcohol 4-0-glucosyltransferase (3), cinnamyl alcohol 4-0-glucoside glucosidase (4).

The activity of cinnamyl alcohol dehydrogenase (CAD EC 1.1.1.195) was already described in the 1970s and was mainly investigated with respect to lignin biosynthesis (see Petersen et al, 1999, for further information). It catalyses the reduction of cinnamaldehydes to cinnamyl alcohols with the help of NADPH the reaction is readily reversible (Fig. 4.7). From a functional point of view, CAD activity is involved in developmental lignification and in the formation of defence compounds. Several reviews have treated the involvement of this enzyme in lignin monomer formation (Boudet et al, 1998,... 

Kim, S.J., Kim, K.W., Cho, M.H., Franceschi, V., Davin, L.B. and Lewis, N.G. (2007) Expression of cinnamyl alcohol dehydrogenases and their putative homologues during Arabidopsis thaliana growth and development Lessons for database annotations Phytochemistry, 68,1957-74. 

Valencia, E., Larroy, C., Ochoa, W.F., Pares, X., Pita, I. and Biosca, J.A. (2004) Apo and holo structures of an NADP(H)-dependent cinnamyl alcohol dehydrogenase from Saccharomyces cerevisiae.. Mol. Biol., 341,1049-62. 

Youn, B., Camacho, R., Moinuddin, S.G.A., Lee, C., Davin, L.B., Lewis, N.G., Kang, C.H. (2006a) Crystal structures and catalytic mechanism of the Arabidopsis cinnamyl alcohol dehydrogenases AtCADS and AtCAD4. Org. Biomol. Chem., 4,1687-97. 

H Kim, J Ralph, F Lu, G Pilate, J-C Leple, B Pollet, C Lapierre. Identification of the structure and origin of thioacidolysis marker compounds for cinnamyl alcohol dehydrogenase deficiency in angiosperms. J Biol Chem 277 47412-47419, 2002. 

---