David Rhodes Professor Ph.D. Area of Interest: Plant metabolic adaptations to environmental stress, with particular emphasis on the biochemical genetics of quaternary ammonium and tertiary sulfonium compound synthesis. E-mail: CV

Teaching Responsibilities

• HORT 410, Vegetable Crops
• HORT 603, Grants and Grantsmanship
• HORT 640, Metabolic Plant Physiology

PULSe - Interdisciplinary Life Science Training Group

Research Activity

Research interests are in plant metabolic adaptations to environmental stress, with particular emphasis on the biochemical genetics of quaternary ammonium and tertiary sulfonium compound synthesis. Quaternary ammonium and tertiary sulfonium compounds are thought to function as compatible cytoplasmic osmotic solutes, and may play a role in plant adaptation to salinity, drought, high temperature and cold temperature stresses. Genes encoding enzymes of quaternary ammonium and tertiary sulfonium compound synthesis are rational candidates for metabolic engineering of plant stress tolerance.

Current research in this laboratory is primarily focused on characterizing genes determining the synthesis of the quaternary ammonium compounds glycinebetaine and nicotinic acid betaine (trigonelline) in maize, elucidating the pathway of synthesis of the tertiary sulfonium compound 3-dimethylsulfoniopropionate (DMSP) in marine algae and higher plants, and developing computer models for interpreting in vivo isotopic labeling data in plant metabolism. Recent emphasis is on analysis of labeling kinetics of intermediates in the pathways of biosynthesis of floral volatiles in snapdragon and petunia (collaboration with Natalia Dudareva).

 

Selected Publications

 

• Orlova, I., Marshall-Colon, A., Schnepp, J., Wood, B., Varbanova, M., Fridman, E., Blakeslee, J.J., Peer, W.A., Murphy, A.S., Rhodes, D., Pichersky, E., Dudareva, N. 2007. Reduction in the synthesis of benzenoids in petunia flowers reveals multiple pathways to benzoic acid and an unexpected enhancement in auxin transport. Plant Cell [In Press].
• Kaminaga, Y., Schnepp, J., Peel, G., Kish, C.M., Ben-Nissan, G., Weiss, D., Orlova, I., Lavie, O., Rhodes, D., Wood, K., Porterfield, D.M., Cooper, A.J., Schloss, J.V., Pichersky, E., Vainstein, A., Dudareva, N. 2006. Plant phenylacetaldehyde synthase is a bifunctional homotetrameric enzyme that catalyzes phenylalanine decarboxylation and oxidation. J. Biol. Chem. 281: 23357-23366.
• Dudareva, N., Andersson, S., Orlova, I., Gatto, N., Reichelt, M., Rhodes, D., Boland, W., Gershenzon, J. 2005. The non-mevalonate pathway supports both monoterpene and sesquiterpene formation in snapdragon flowers. Proc. Natl. Acad. Sci. U.S.A. 102: 933-938.
• Boatright, J., Negre, F., Chen, X., Kish, C.M., Wood, B., Peel, G., Orlova, I., Gang, D., Rhodes, D. and Dudareva, N. 2004. Understanding in vivo benzenoid metabolism in petunia petal tissue. Plant Physiology 135: 1993-2011.
• Inan, G., Zhang, Q., Li, P., Wang, Z., Cao, Z., Zhang, H., Zhang, C., Quist, T.M., Goodwin, S.M., Zhu, J., Shi, H., Damsz, B., Charbaji, T., Gong, Q., Ma, S., Fredricksen, M., Galbraith, D.W., Jenks, M.A., Rhodes, D., Hasegawa, P.M., Bohnert, H.J., Joly, R.J., Bressan, R.A. and Zhu, J.K. 2004. Salt cress. A halophyte and cryophyte Arabidopsis relative model system and its applicability to molecular genetic analyses of growth and development of extremophiles. Plant Physiology 135: 1718-1737.
• Goyer, A., Johnson, T.L., Olsen, L.J., Collakova, E., Shachar-Hill, Y., Rhodes, D. and Hanson, A.D. 2004. Characterization and metabolic function of a peroxisomal sarcosine and pipecolate oxidase from Arabidopsis. Journal of Biological Chemistry 279: 16947-16953.
• Rhodes, D., Peel, G.J. and Dudareva N. 2004. Engineering pathways of secondary metabolism. In (R.M. Goodman, ed) "Encyclopedia of Plant and Crop Science", Marcel Dekker, N.Y, pp. 720-723.
• Rhodes, D., McNeil, S.D., Nuccio, M.L. and Hanson, A.D. 2004. Metabolic engineering and flux analysis of glycine betaine synthesis in plants: progress and prospects. In (B.N. Kholodenko, H.V. Westerhoff, eds.) "Metabolic Engineering in the Post Genomic Era", Horizon Bioscience, Wymondham, Norfolk, U.K., pp. 409-434.
• Rontein, D., Rhodes, D. and Hanson, A.D. 2003. Evidence from engineering that decarboxylation of free serine is the major source of ethanolamine moieties in plants. Plant & Cell Physiology 44: 1185-1191.
• Mickelbart, M.V., Peel, G., Joly, R.J., Rhodes, D., Ejeta, G. and Goldsbrough, P.B. 2003. Development and characterization of near-isogenic lines of sorghum segregating for glycinebetaine accumulation. Physiologia Plantarum 118: 253-261.
• Kocsis, M.G., Ranocha, P., Gage, D.A., Simon, E.S., Rhodes, D., Peel, G.J., Mellema, S., Saito, K., Awazuhara, M., Li, C., Meeley, R.B., Tarczynski, M.C., Wagner, C. and Hanson, A.D. 2003. Insertional inactivation of the methionine S-methyltransferase gene eliminates the S-methylmethionine cycle and increases the methylation ratio. Plant Physiology 131: 1808-1815.
• Yang, W.-J., Rich, P.J., Axtell, J.D., Wood, K.V., Bonham, C.C., Ejeta, G., Mickelbart, M.V. and Rhodes, D. 2003. Genotypic variation for glycinebetaine in sorghum. Crop Science 43: 162-169.
• Rhodes, D., Nadolska-Orczyk, A. and Rich, P.J. 2002. Salinity, osmolytes and compatible solutes. In (A. Lauchli, U. Luttge, eds.) "Salinity: Environment - Plants - Molecules", Kluwer Academic, Boston, N.Y., pp. 181-204.
• Wood, K.V., Bonham, C.C., Miles, D., Rothwell, A.P., Peel, G., Wood, B.C. and Rhodes, D. 2002. Characterization of betaines using electrospray MS/MS. Phytochemistry 59: 759-765.
• Morgan, J.A. and Rhodes, D. 2002. Mathematical modeling of plant metabolic pathways. Metabolic Engineering 4: 80-89.
• Fletcher, S.A., Rhodes, D. and Csonka, L.N. 2001. Analysis of the effects of osmoprotectants on the high osmolality-dependent induction of increased thermotolerance in Salmonella typhimurium. Food Microbiology 18: 345-354.
• McNeil, S.D., Rhodes, D., Russell, B.L., Nuccio, M.L., Shachar-Hill, Y. and Hanson, A.D. 2000. Metabolic modeling identifies key constraints on an engineered glycine betaine synthesis pathway in tobacco. Plant Physiology 124: 153-162.
• Ranocha, P., Bourgis, F., Ziemak, M.J., Rhodes, D., Gage, D.A. and Hanson, A.D. 2000. Characterization and functional expression of cDNAs encoding methionine-sensitive and -insensitive homocysteine S-methyltransferases from Arabidopsis. J. Biol. Chem. 275: 15962-15968.
• Jenks, M.A., Rich, P.J., Rhodes, D., Ashworth, E.N., Axtell, J.D. and Ding, C.-K. 2000. Leaf sheath cuticular waxes on bloomless and sparse-bloom mutants of Sorghum bicolor. Phytochemistry 54: 577-584.
• McNeil, S.D., Nuccio, M.L., Rhodes, D., Shachar-Hill, Y. and Hanson, A.D. 2000. Radiotracer and computer modeling evidence that phosphobase methylation is the main route of choline synthesis in tobacco. Plant Physiology 123: 371-380.
• Joly, R.J., Jones, M.L., Verlinden, S., Rhodes, D. and Woodson, W.R. 2000. Learning in an inquiry-driven plant physiology laboratory. Journal of Natural Resources and Life Sciences Education 29: 31-35.
• Rhodes, D. and Nadolska-Orczyk, A. 1999. Plant stress physiology. In "Encyclopedia of Life Sciences". Macmillan References Ltd., London (http://www.els.net).
• Nuccio, M.L., Rhodes, D., McNeil, S.D. and Hanson, A.D. 1999. Metabolic engineering of plants for osmotic stress resistance. Current Opin. Plant Biol. 2: 128-134.
• Kocsis, M.G., Nolte, K.D., Rhodes, D., Shen, T.L., Gage, D.A. and Hanson, A.D. 1998. Dimethylsulfoniopropionate biosynthesis in Spartina alterniflora Loisel.: evidence that S-methylmethionine and dimethylsulfoniopropylamine are intermediates. Plant Physiology 117: 263-271.
• Summers, P.S., Nolte, K.D., Cooper, A.J.L., Borgeas, H., Leustek T., Rhodes, D. and Hanson, A.D. 1998. Identification and stereospecificity of the first three enzymes of 3-dimethylsulfoniopropionate biosynthesis in a chlorophyte alga. Plant Physiology 116: 369-378.
• Rhodes, D., Gage, D.A., Cooper, A.J.L. and Hanson, A.D. 1997. S-Methylmethionine conversion to dimethylsulfoniopropionate: evidence for an unusual transamination reaction. Plant Physiology 115: 1541-1548.
• Canovas, D., Vargas, C., Iglesias-Guerra, F., Csonka, L.N., Rhodes, D., Ventosa, A. and Nieto, J.J. 1997. Isolation and characterization of salt-sensitive mutants of the moderate halophile Halomonas elongata and cloning of the ectoine synthesis genes. Journal of Biological Chemistry 272: 25794-25801.
• Gage, D.A., Rhodes, D., Nolte, K.D., Hicks, W.A., Leustek, T., Cooper, A.J.L. and Hanson, A.D. 1997. A new route for synthesis of dimethylsulphoniopropionate in marine algae. Nature 387: 891-894.
• Yang, G., Rhodes, D. and Joly, R.J. 1996. Effects of high temperature on membrane stability and chlorophyll fluorescence in glycinebetaine-deficient and -containing maize lines. Australian Journal of Plant Physiology 23: 437-443.
• Sheets, E.B. and Rhodes, D. 1996. Determination of DMSP and other onium compounds in Tetraselmis subcordiformis by plasma desorption mass spectrometry.In (R. Kiene, P. Visscher, G. Kirst, M. Keller, eds.) "Biological and Environmental Chemistry of Dimethylsulfoniopropionate and Related Sulfonium Compounds." Plenum Press, New York. pp. 55-63.
• Wood, A.J., Saneoka, H., Rhodes, D., Joly, R.J. and Goldsbrough, P.B. 1996. Betaine aldehyde dehydrogenase in sorghum: molecular cloning and expression of two related genes. Plant Physiology 110: 1301-1308.
• Bonham, C.C., Wood, K.V, Yang, W-J., Nadolska-Orczyk, A., Samaras, Y., Gage, D.A., Poupart, J., Burnet, M., Hanson, A.D. and Rhodes, D. 1995. Identification of quaternary ammonium and tertiary sulfonium compounds by plasma desorption mass spectrometry. Journal of Mass Spectrometry 30: 1187-1194.
• Yang, W.-J., Nadolska-Orczyk, A., Wood, K.V., Hahn, D.T., Rich, P.J., Wood, A.J., Saneoka, H., Premachandra, G.S., Bonham, C.C., Rhodes, J.C., Joly, R.J., Samaras, Y., Goldsbrough, P.B. and Rhodes, D. 1995. Near-isogenic lines of maize differing for glycinebetaine. Plant Physiology 107: 621-630.
• Saneoka, H., Nagasaka, C., Hahn, D.T., Yang, W.-J., Premachandra, G.S., Joly, R.J. and Rhodes, D. 1995. Salt tolerance of glycinebetaine-deficient and -containing maize lines. Plant Physiology 107: 631-638.
• Premachandra G.S., Hahn, D.T., Rhodes, D. and Joly, R.J. 1995. Leaf water relations and solute accumulation in two grain sorghum lines exhibiting contrasting drought tolerance. Journal of Experimental Botany 46: 1833-1841.
• Samaras, Y., Bressan, R.A., Csonka, L.N., Garcia-Rios, M.G., Paino D'Urzo, M. and Rhodes, D. 1995. Proline accumulation during drought and salinity.In (N. Smirnoff, ed.) "Environment and Plant Metabolism." Bios Scientific Publishers, Oxford, pp. 161-187.
• Grote, E.M., Ejeta, G. and Rhodes, D. 1994. Inheritance of glycinebetaine deficiency in sorghum. Crop Science 34: 1217-1220.
• Rhodes, D. and Hanson, A.D. 1993. Quaternary ammonium and tertiary sulfonium compounds in higher plants. Annu. Rev. Plant Physiol. Plant Mol. Biol. 44: 357-384.

---