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Washington State University Molecular Plant Sciences


WSU Regents Professor, Fellow of the Institute of Biological Chemistry, Fellow of the Royal Society of Edinburgh, The Arthur M. and Kate Eisig-Tode Distinguished Professor. Ph.D.1977, University of British Columbia.



The single most important feature in distinguishing terrestrial vascular plants from their aquatic counterparts lies in the composition and amounts of their phenylpropanoid metabolites. In vascular plants, this pathway provides major classes of organic compounds of specialized function and structure. These include neolignans and lignans, structural cell wall polymers (lignins and the aromatic portion of suberins), proanthocyanidins (condensed tannins, i.e., its phenylalanine derived portion), and related compounds. Without this pathway, the normal growth, development and survival of both woody and nonwoody plants would not be possible. Indeed, since approximately 10 to 45% of all vascular plant material is of phenylpropanoid origin, these metabolites constitute a major sink of organic carbon.

Although all of the roles of these compounds have not yet been identified, it is known that they provide structural reinforcement to plant tissue, can act as phytoalexins, and function as phytotoxins against fungi, bacteria, insects and other herbivores. Many have important pharmacological activities in man, including anticancer activities.

Our research program examines various aspects of phenylpropanoid metabolism, with a particular emphasis toward understanding vascular plant cell wall formation. We have developed sensitive [13C] labeling methods to monitor phenylpropanoid metabolism in situ, have detected several enzymes of highly unusual specificity in lignan and monolignol glucoside formation, and are studying the factors regulating carbon flow into various offshoots of this pathway.

The effects of stress (e.g., gravitational field strength) on plant growth and development is also being actively pursued, e.g., at the enzymatic and ultrastructural level. Other related research projects include tannin, carbohydrate (i.e., cellulose) and diterpenoid (i.e., to taxol, a potent anticancer agent) metabolism and phenylpropanoid biodegradation.

Selected publications

Teoh, K.H., Ford, J.D., Kim, M.-R., Davin, L.B. and Lewis, N.G. 2008. Delineating the metabolic pathway(s) to secoisolariciresinol diglucoside hydroxymethylglutarate oligomers in flaxseed (Linum usitatissimum). Focus on Omega 3. (Lands, W.E.M.), AOCS Press, pp.41-62.

Davin, L.B., Jourdes, M., Patten, A.M., Vassão, D.G. and Lewis, N.G. 2008. Dissection of lignin macromolecular configuration and assembly: Comparison to related biochemical processes in allyl/propenyl phenol and lignan biosynthesis. Natural Product Reports (doi 10.1039/B510386J).

Patten, A.M., Davin, L.B., Lewis, N.G. 2008. Relationship of dirigent protein and 18s RNA localization to heartwood formation in western red cedar. Phytochemistry doi:10.1016/j.phytochem.2008.06.020.

Davin, L.B., Patten, A.M., Jourdes, M. and Lewis, N.G. 2008. Lignins: A 21st century challenge. In “Biomass Recalcitrance” Chapter 7 (Himmel, M., Ed.), Blackwell Publishing Ltd, Oxford, UK, pp. 213-305.

Vassão, D.G., Davin, L.B. and Lewis, N.G. 2008. Metabolic engineering of plant allyl/propenyl phenol and lignin pathways: Future potential for biofuels/bioenergy, polymer intermediates and specialty chemicals? In “Advances in Plant Biochemistry and Molecular Biology” (Lewis, N.G., Ed.-in-Chief), Vol. 1, Bioengineering and Molecular Biology of Plant Pathways (Bohnert, H.J. and Nguyen, H.T, eds.), Elsevier Publishers, Oxford, UK, pp. 385-421. Vassão, D.G., Kim, S.-J., Milhollan, J.K., Eichinger, D., Davin, L.B. and Lewis, N.G. 2007. A pinoresinol-lariciresinol reductase homologue from the creosote bush (Larrea tridentata) catalyzes the efficient in vitro conversion of p-coumaryl/coniferyl alcohol esters into the allylphenols chavicol/eugenol, but not the propenylphenols p-anol/isoeugenol. Arch. Biochem. Biophys. 465:209–218.

Kim, S.-J, Kim, K.-W., Cho, M.-H., Franceschi, V.R. (deceased), 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(14):1956-1973.

Jourdes, M., Cardenas, C.L., Laskar, D.D., Moinuddin, S.G.A., Davin, L.B. and Lewis, N.G. 2007. Plant cell walls are enfeebled when attempting to preserve native lignin configuration with poly-p-hydroxycinnamaldehydes: Evolutionary implications. Phytochemistry 68(14):1931-1955. (Cover page article.)

Patten, A.M., Jourdes, M., Brown, E.E., Laborie, M.-P., Davin, L.B. and Lewis, N.G. 2007. Reaction tissue formation and stem tensile modulus properties in wild-type and p-coumarate-3-hydroxylase downregulated lines of alfalfa, Medicago sativa (Fabaceae). Am. J. Bot. 94(6):912-924. (Cover page article.)

Cho, M.-H., Corea, O.R.A., Yang, H. Bedgar, D.L., Laskar, D.D., Anterola, A.M., Moog-Anterola, F.A., Hood, R.L., Kohalmi, S.E., Bernards, M.A., Kang, C., Davin, L.B. and Lewis, N.G. 2007. Phenylalanine biosynthesis in Arabidopsis thaliana: Identification and characterization of arogenate dehydratases. J. Biol. Chem. 282:30827-30835.

Youn, B., Kim, S.-J., Moinuddin, S.G.A., Lee, C., Bedgar, D.L., Harper, A.R., Davin, L.B., Lewis, N.G. and Kang, C.H. 2006. Mechanistic and structural studies of apo-form, binary, and ternary complexes of the Arabidopsis alkenal double bond reductase At5g16970. J. Biol. Chem. 281(52):40076-40088.

Kasahara, H., Jiao, Y., Bedgar, D.L., Kim, S.-J., Patten, A.M., Xia, Z.-Q., Davin, L.B. and Lewis, N.G. 2006. Pinus taeda phenylpropenal double-bond reductase: Purification, cDNA cloning, heterologous expression in Escherichia coli, and subcellular localization in P. taeda. Phytochemistry 67(16):1765-1780.

Koeduka, T., Fridman, E., Gang, D. R., Vassão, D.G., Jackson, B.L., Kish, C.M., Orlova, I., Spassova, S.M., Lewis, N.G., Noel, J.P., Baiga, T.J., Dudareva, N. and Pichersky, E. 2006. Eugenol and isoeugenol, characteristic aromatic constituents of spices, are biosynthesized via reduction of coniferyl alcohol ester. Proc. Natl. Acad. Sci. USA 103(26):10128-10133.

Vassão, D.G., Gang, D.R., Kueduka, T., Jackson, B., Pichersky, E., Davin, L.B. and Lewis, N.G. 2006. Chavicol formation in sweet basil (Ocimum basilicum): cleavage of an esterified C9 hydroxyl group with NAD(P)H-dependent reduction. Org. Biomol. Chem. 4(14):2733-2744. Laskar, D.D., Jourdes, M., Patten, A.M., Helms, G.L., Davin, L.B. and Lewis, N.G. 2006. The Arabidopsis cinnamoyl CoA reductase irx4 mutant has a delayed, but coherent (normal) program of lignification. Plant J. 48(5):674-686.

Youn, B., Camacho, R., Moinuddin, S.G.A., Lee, C., Davin, L.B., Lewis, N.G. and Kang, C. 2006. Crystal structures and catalytic mechanism of the Arabidopsis cinnamyl alcohol dehydrogenases AtCAD5 and AtCAD4. Org. Biomol. Chem. 4:1687-1697.

Moinuddin, S.G.A., Youn, B.H., Bedgar, D.L., Costa, M.A., Helms, G.L., Kang, C.H., Davin, L.B. and Lewis, N.G. 2006. Secoisolariciresinol dehydrogenase: mode of catalysis and stereospecificity of hydride transfer in Podophyllum peltatum. Org. Biomol. Chem. 4:808-816. (Cover page article.)

Kim, K.-W., Franceschi, V.R., Davin, L.B. and Lewis, N.G. 2006. b-Glucuronidase as reporter gene: Advantages and limitations. In “Methods in Molecular Biology” vol. 323: Arabidopsis Protocols, Second Edition (Salinas, J. and Sanchez-Serrano, J.J., eds.), Methods in Molecular Biology Series. Vol. 271. Humana Press, Inc., Totowa, NJ. pp. 263-273. (Cover page article.)

Lewis, N.G. 2006. Anniversary – David I. Goring 85. Cellulose Chemistry and Technology 40(3-4):145-147.

Lewis, N.G., Bolwell, G.P., Strack, D. 2006. Editorial: Special issue dedicated to Prof. Rodney B. Croteau on his 60th birthday. Phytochemistry 67(15):1560-1561; 67(16):1704-1705.

Davin, L.B. and Lewis, N.G. 2005. Lignin primary structures and dirigent sites. Curr. Opin. Biotechnol. 16:407-415.

Davin, L.B. and Lewis, N.G. 2005. Dirigent phenoxy radical coupling: Advances and challenges. Curr. Opin. Biotechnol. 16:398-406.

Costa, M.A., Bedgar, D.L., Moinuddin, S.G.A., Kim, K.-W., Cardenas, C.L., Cochrane, F.C., Shockey, J.M., Helms, G.L., Amakura, Y., Takahashi, H., Milhollan, J.K., Davin, L.B., Browse, J. and Lewis, N.G. 2005. Characterization in vitro and in vivo of the putative multigene 4-coumarate:CoA ligase network in Arabidopsis: syringyl lignin and sinapate/sinapyl alcohol derivative formation. Phytochemistry 66(17):2072-2091.

Patten, A.M., Cardenas, C.L., Cochrane, F.C., Laskar, D., Bedgar, D.L., Davin, L.B. and Lewis, N.G. 2005. Reassessment of effects on lignification and vascular development in the irx4 Arabidopsis mutant. Phytochemistry 66(17):2092-2107.

Youn, B.H., Moinuddin, S.G.A., Davin, L.B., Lewis, N.G. and Kang, C.H. 2005. Crystal structures of apo-form, binary and ternary complexes of Podophyllum secoisolariciresinol dehydrogenase, an enzyme involved in formation of health-protecting and plant defense lignans. J. Biol. Chem. 280(13):12917-12926.

Ehrenkranz, J.R.L., Lewis, N.G. and Kahn, C.R. 2005. Phlorizin: A review. Diabetes Metab. Res. Rev. 21:31-38.

Cochrane, F.C., Davin, L.B. and Lewis, N.G. 2004. The Arabidopsis phenylalanine ammonia lyase gene family: Kinetic characterization of the four PAL isoforms. Phytochemistry 65:1557-1564.

Davin, L.B. and Lewis, N.G. 2004. An historical perspective on lignan biosynthesis: monolignol, allylphenol and hydroxycinnamic acid coupling and downstream metabolism. Phytochemistry Rev. 3:257-288 (2003).

Halls, S., Davin, L.B., Kramer, D.M. and Lewis, N.G. 2004. Kinetic study of coniferyl alcohol radical binding to the (+)-pinoresinol forming dirigent protein. Biochemistry 43(9):2587-2595.

Kim, S.-J., Kim, M.-R., Bedgar, D.L., Moinuddin, S.G.A., Cardenas, C.L., Davin, L.B., Kang, C.H. and Lewis, N.G. 2004. Functional reclassification of the putative cinnamyl alcohol dehydrogenase multigene family in Arabidopsis. Proc. Natl. Acad. Sci. USA 101(6):1455-1460.

Min, T., Kasahara, H., Bedgar, D.L., Youn, B., Lawrence, P.K., Gang, D.R., Halls, S.C., Park, H.J., Hilsenbeck, J.L., Davin, L.B., Lewis, N.G. and Kang, C.H. 2003. Crystal structures of pinoresinol-lariciresinol and phenylcoumaran benzylic ether reductases, and their relationship to isoflavone reductases. J. Biol. Chem. 278(50):50714-50723.

Cho, M.-H., Moinuddin, S.G.A., Helms, G.L., Hishiyama, S., Eichinger, D., Davin, L.B. and Lewis, N.G. 2003. (+)-Larreatricin hydroxylase, an enantio-specific polyphenol oxidase from the creosote bush (Larrea tridentata). Proc. Natl. Acad. Sci. USA 100(19):10641-10646.

Medeiros, J.R., Campos, L.B., Mendonca, S.C., Davin, L.B. and Lewis, N.G. 2003. Composition and antimicrobial activity of the essential oils from invasive species of the Azores, Hedychium gardnerianumn and Pittosporum undulatum. Phytochemistry 64(2):561-565.

Moinuddin, S.G.A., Hishiyama, S., Cho, M.-H., Davin, L.B. and Lewis, N.G. 2003. Synthesis and chiral HPLC analysis of the diphenyltetrahydrofuran lignans, larreatricins, 8¢-epi-larreatricins, 3,3¢-didemethoxyverrucosins and meso-3,3¢-didemethoxynectandrin B in the creosote bush (Larrea tridentata): Evidence for regiospecific control of coupling. Organic and Biomolecular Chemistry, 1(13):2307-2313.

Blee, K., Choi, J.W., O’Connell, A.P., Schuch, W., Lewis, N.G. and Bolwell, G.P. 2003. A lignin-specific peroxidase in tobacco whose antisense suppression leads to vascular tissue modification. Phytochemistry 64(1):163-176.

Costa, M.A., Collins, R.E., Anterola, A.M., Cochrane, F.C., Davin, L.B. and Lewis, N.G. 2003. An in silico assessment of gene function and organization of the phenylpropanoid pathway metabolic networks in Arabidopsis thaliana and limitations thereof. Phytochemistry 64(6):1097-1112.

Medeiros, J.R., Medeiros, N., Medeiros, H., Davin, L.B. and Lewis, N.G. 2003. Composition of the bioactive essential oils from the leaves of Eugenia stipitata McVaugh ssp. sororia from the Azores. J. Essent. Oil Res. 15(4):293-295.

Teoh, K.H., Ford, J.D., Kim, M.-R., Davin, L.B., Lewis, N.G. 2003. Delineating the metabolic pathway(s) to secoisolariciresinol diglucoside hydroxymethyl glutarate oligo- mers in flaxseed (Linum usitatissimum). In: Flaxseed in Human Nutrition, second edition (Cunnane, S.C., Thompson, L.U., Eds.), AOCS Press, Champaign, Illinois, pp. 41-62.

Halls, S.C. and Lewis, N.G. 2003. Reversed-phase HPLC lignan chiral analyses with laser polarimetric detection. Tetrahedron: Asymmetry 14(6):649-658.

Davin, L.B., Wang, C.-Z., Helms, G.C. and Lewis, N.G. 2003. [13C]-Specific labeling of 8–2¢ linked (–)-cis-blechnic, (–)-trans-blechnic and (–)-brainic acids in the fern Blechnum spicant. Phytochemistry 62(3):501-511.