Michael G. Hahn
Complex Carbohydrate Research Center, Rm 2507
Phone Number:  706-542-4457
Office/Lab:  Complex Carbohydrate Research Center, Rm 2048
Phone Number: 

Ph.D Chemistry, University of Colorado 1981

Research Projects: 

Our laboratory studies the cell biology and biosynthesis of plant cell walls. Plant cell walls play major roles in the biology of plants. Examples of these roles include controlling the growth and shape of plant cells, tissues, organs, and ultimately the entire plant, regulating the movement of nutrients and signals within the apoplast and toward the plasma membrane, serving as the first line of defense against pathogens and environmental stresses, and acting as a source of signaling molecules important in plant development and defense. Plant cell walls are also the principal component of plant biomass, which has become a focal point in the search for alternative and renewable sources of energy (biofuels).

We are pursuing two broad research goals:

(A) We are investigating plant cell wall biosynthesis by looking at two families of genes, primarily in Arabidopsis, thought to encode glycosyltransferases involved in plant cell wall glycan biosynthesis: 1) GAlacturonosylTransferase-Like (GATL) proteins thought to be involved in pectin biosynthesis; 2) FUcosylTransferase (FUT) proteins thought to add fucosyl residues to diverse plant cell wall glycans.

(B) We have developed a large and diverse library of monoclonal antibodies against plant cell wall glycans. These antibodies are being used to determine the locations of diverse cell wall carbohydrate structures (epitopes) in Arabidopsis, switchgrass and poplar. These antibodies are also proving useful for plant cell wall mutant characterization studies, and for quantitating glycans in cell wall extracts.

Our laboratory utilizes a broad range of experimental approaches in these studies, including molecular genetic, biochemical, immunological and microscopic techniques.

Grant Support: 
  • National Science Foundation - “VCA: A Monoclonal Antibody Toolkit for Functional Genomics of Plant Cell Walls.” 2004-2009.
  • National Science Foundation - “Dissecting the Molecular Mechanism of Pectin Synthesis in Arabidopsis." 2007-2011.
  • National Science Foundation - “TRPGR: A Toolkit for in vivo Visualization/Modulation of Plant Cell Wall Polysaccharides.” 2010-2014.
  • Department of Energy - “Structural Studies of Complex Carbohydrates of Plant Cell Walls." 2008-2011
  • Department of Energy - “Understanding the mechanism by which non-catalytic carbohydrate binding modules contribute to plant cell wall degradation.” 2009-2012.
  • Department of Energy - “BioEnergy Science Center (BESC).” 2007-2012.
Of Note: 
  • Invited chair of session on “New Technologies in Glycobiology” at the Gordon Research Conference on Plant Cell Walls, University of New England, Biddeford, ME. July 30-August 4, 2006.
  • Chair, Organizing Committee for the Albersheim Retirement Symposium, University of Georgia, Complex Carbohydrate Research Center. April 30, 2007.
Selected Publications: 
  • Biswal, A.K., K. Soeno, M.L. Gandla, P. Immerzeel, S. Pattathil, J. Lucenius, R. Serimaa, M.G. Hahn, T. Moritza, L.J. Jönsson, Israelsson-Nordström and E.J. Mellerowicz. 2014. Aspen PL1 family pectate lyase PtxtPL1-27 mobilizes matrix polysaccharides from woody tissues and improves saccharification yield. Biotechnology for Biofuels, in press.
  • Zhang, X., A. Rogowski, M.G. Hahn, U. A vci, J.P . Knox and H.J. Gilbert. 2013. Understanding how the complex molecular architecture of mannan degrading hydrolases contributes to plant cell wall degradation. J. Biol. Chem., 24: 289(4) 2002-12.
  • Ratnaparkhe, S., S. Venkatachalam, M.G. Hahn, and S. Pattathil. 2013. Analyses using cell wall glycan-directed monoclonal antibodies reveal xylan-degradation by two microbial glycosyl hydrolases in cell walls from poplar and switchgrass biomass. J. Bioremed. Biodeg., in press.
  • Liang, Y., S. Pattathil, W.-L Xu, D. Basu, A. Venetos, A. Faik, M.G. Hahn, and A.M. Showalter. 2013. Biochemical and physiological characterization of fut4 and fut6 mutants defective in arabinogalactan-protein fucosylation in Arabidopsis. J. Exp. Botany 64(18): 5537-51.
  • Kong, Y., G. Zhou, M. Atmodjo, A.M.A. Abdeen, T. Western, D. Mohnen and M.G. Hahn. 2013. The Arabidopsis AtGATL5 gene is involved in the production of seed coat mucilage. Plant Physiology 163: 1203-1217.
  • Zhao, Q., Y. Tobimatsu, R. Zhou, S. Pattathil, L. Gallego-Giraldo, C. Fu, L.A. Jackson, M.G. Hahn, H. Kim, F. Chen, J. Ralph, and R.A. Dixon. 2013. Loss of function of CAD1 leads to unconventional lignin and a temperature-sensitive growth defect in Medicago truncatula. Proc. Natl. Acad. Sci. USA 110: 13660-13665.
  • Kataeva, I., M. Foston, S.-J. Yang, S. Pattathil, A.K. Biswal, F.L. Poole II, T.P. Thomas, P. Azadi, V. Olman, D.L. Lewis, C. Doeppke, T. Tschaplinsky, M. Davis, D. Mohnen, Y. Xu, A. Ragauskas, R.M. Kelly, M.G. Hahn and M.W.W. Adams. 2013. Extremely thermophilic bacteria exploit high temperature to deconstruct untreated plant biomass. Energy Environ. Sci. 6: 2186-2195.
  • Shen, H., C.R. Poovaiah, A. Ziebell, T.J. Tschaplinski, S. Pattathil, E. Gjersing, N.L. Engle, R. Katahira, Y. Pu, R. Sykes, F. Chen, A.J. Ragauskas, J.R. Mielenz, M.G. Hahn, M. Davis, C.N. Stewart Jr. and R.A Dixon. 2013. Enhanced characteristics of genetically modified switchgrass (Panicum virgatum L.) for high biofuel production. Biotechnology for Biofuels 6: 71 (DOI:10.1186/1754-6834-6-71).
  • Avci, U., S. Pattathil, B. Singh, V.L. Brown, M.G. Hahn and C.H. Haigler. 2013. Comparison of cotton fiber cell wall structure and remodeling in two commercial Gossypium species with different fiber quality characteristics. PLOS One, in press.
  • Tan, L., S. Eberhard, C. Warder, S. Pattathil, C. Yuan, J. Glushka, X. Zhu, U. Avci, J.S. Miller, D. Baldwin, C. Pham, R. Orlando, M.G. Hahn, A. Darvill, M. Kieliszewski and D. Mohnen. 2013. Plant cell walls have an arabinoxylan-pectin-arabinogalactan protein (APAP) substructure. Plant Cell (DOI: 10.1105/ tpc.112.107334).
  • DeMartini, J.D., S. Pattathil, J.S. Miller, H. Li, M.G. Hahn and C.E. Wyman. 2013. Investigating plant cell wall components that affect biomass recalcitrance in poplar and switchgrass. Energy Environ. Sci. (DOI: 10.1039/c3ee23801f).
  • de Souza, A.P., D.C.C. Leite, S. Pattathil, M.G. Hahn, and M.S. Buckeridge. 2012. Composition and structure of sugarcane cell wall polysaccharides: Implications for second generation bioethanol production. Bioenergy Research (DOI 10.1007/s12155-012-9268-1).
  • Kulkarni, A.R., S. Pattathil, M.G. Hahn, W.S. York, and M.A. O'Neill. 2012. Comparison of arabinoxylan structure in bioenergy and model grasses. Indust. Biotechnol. 8: 222-229.
  • Pattathil, S., T. Saffold, L. Gallego-Giraldo, M. O’Neill, W.S York, R.A. Dixon and M.G Hahn. 2012. Changes in cell wall carbohydrate extractability are correlated with reduced recalcitrance of HCT down-regulated alfalfa biomass. Indust. Biotechnol. 8: 217-221.
  • Zabotina, O.A., U. Avci, D. Cavalier, S. Pattathil, Y.-H. Chou, S. Eberhard, L. Danhof, K. Keegstra and M.G. Hahn. 2012. Multiple mutations in XXT genes of Arabidopsis reveal complexities in xylosyltransferase functions during xyloglucan biosynthesis. Plant Physiol. 159: 1367-1384.
  • Duceppe, M.-O., A. Bertrand, S. Pattathil, J. Miller, Y. Castonguay, M.G. Hahn, R. Michaud, and M.-P. Dubé. 2012. Assessment of genetic variability and selection for cell wall degradability in alfalfa stems. BioEnergy Research 5: 904-914.
  • Lee, S.J., T.A. Warnick, S. Pattathill, J.G. Alvelo-Maurosa, M.J. Serapiglia, N.F. Young, D.J. Schnell, L.B. Smart, M.G. Hahn, J.F. Pedersen, S.B. Leschine and S.P. Hazen. 2012. Genetic variation within energy crop species for biological conversion quality. Biotechnol. Biofuels 5: 5 (DOI: 10.1186/1754-6834-5-5).
  • Dutta, B., U. Avci, M.G. Hahn and R.R. Walcott. 2012. Location of Acidovorax citrulli in infested watermelon seeds is influenced by the pathway of bacterial invasion. Phytopathology 102: 461-468.
  • Kulkarni, A., M. J.Peña, U. Avci, K. Mazumdar, B. Urbanowicz, Y. Yin, M.A. O’Neill, A.W. Roberts, M.G. Hahn, Y. Xu, A.G. Darvill and W.S.York. 2012. The ability of land plants to synthesize glucuronoxylans predates the evolution of vascular anatomy. Glycobiology 22: 439-451.
  • Pattathil, S., U. Avci, J.S. Miller and M.G. Hahn. 2012. Immunological approaches to plant cell wall and biomass characterization: Glycome Profiling. In: M. Himmel (ed.), Biomass Conversion: Methods and Protocols, Methods in Molecular Biology, Vol. 908, pp. 61-72. Humana Press, New York, NY. DOI 10.1007/978-1-61779-956-3_6.
  • Avci, U., S. Pattathil and M.G. Hahn. 2012. Immunological approaches to plant cell wall and biomass characterization: Immunolocalization of glycan epitopes. In: M. Himmel (ed.), Biomass Conversion: Methods and Protocols, Methods in Molecular Biology, Vol. 908, pp. 73-82. Humana Press, New York, NY. DOI 10.1007/978-1-61779-956-3_7.
  • DeMartini, J.D., S. Pattathil, U. Avci, K. Szekalski, K. Mazumder, M.G. Hahn and C.E. Wyman. 2011. Application of monoclonal antibodies to investigate plant cell wall deconstruction for biofuels production. Energy Environ. Sci. 4: 4332-4339.
  • Klopffleisch, K., N. Phan, K. Augustin, K.S. Booker, J.R. Botella, N.C. Carpita, T. Carr, J.-G. Chen, T.R. Cooke, A. Frick-Cheng, E.J. Friedman, M.G. Hahn, K. Jiang, L. Jorda, L. Kruppe, C. Liu, J. Lorek, M.C. McCann, A. Molina, E.N. Moriyama, M. S. Mukhtar, Y. Mudgil, S. Pattathil, J. Schwarz, S. Seta, M. Tan, U. Temp, Y. Trusov, D. Urano, B. Welter, J. Yang, R. Panstruga, J.F. Uhrig and A.M. Jones. 2011. The Arabidopsis G protein network: linking G protein signaling, cell wall carbohydrates and plant morphogenesis. Molecular Systems Biology 7: 532.
  • Kong, Y., G. Zhou, Y. Yin, S. Pattathil and M.G. Hahn. 2011. Molecular analysis of a family of Arabidopsis genes related to galacturonosyltransferases. Plant Physiol. 155: 1791-1805.
  • Yin, Y., D. Mohnen, I. Gelineo-Albersheim, Y. Xu and M.G. Hahn. 2011. Glycosyltransferases of the GT8 Family. In: P. Ulvskov (ed.), Plant Cell Wall Polysaccharides: Biosynthesis and Bioengineering, Annual Plant Reviews, Vol. 41, pp. 167-212. Blackwell Publications, Chichester, UK.
  • Pattathil, S. U. Avci, D. Baldwin, A.G. Swennes, J.A. McGill, Z. Popper, T. Bootten, A. Albert, R.H. Davis, C. Chenareddy, R. Dong, E. O'Shea, R. Rossi, C. Leoff, G. Freshour, R. Narra, M. O'Neill, W.S. York and M.G. Hahn. 2010. A comprehensive toolkit of plant cell wall glycan-directed monoclonal antibodies. Plant Physiol. 153: 514-525.
  • Wang, H., U. Avci, J. Nakashima, M.G. Hahn, F. Chen and R.A. Dixon. 2010. Mutation of WRKY transcription factors initiates pith secondary wall formation and increases stem biomass in dicotyledonous plants. Proc. Natl. Acad. Sci. USA 107: 22338-22343.
  • Yin, Y., H. Chen, M.G. Hahn, D. Mohnen and Y. Xu. 2010. Evolution and function of the plant cell wall synthesis-related glycosyltransferase family 8. Plant Physiol. 15: 1729-1746.
  • Zhu, X., S. Pattathil, K. Mazumder, A. Brehm, M.G. Hahn, S.P. Dinesh-Kumar and C.P. Joshi. 2010. Virus-induced gene silencing offers a functional genomics platform for studies of plant cell wall formation. Molecular Plant.3: 818-833.
  • Deng, C., M.A. O'Neill, M.G. Hahn and W.S. York. 2009. Improved procedures for the selective chemical fragmentation of rhamnogalacturonans. Carbohydr. Res. 344: 1852-1857.
  • Caffall K.H., S. Pattathil, S.E. Phillips, M.G. Hahn, D. Mohnen. 2009. Arabidopsis thaliana T-DNA mutants implicate GAUT genes in the biosynthesis of cell wall and seed testa pectin and xylan. Molec. Plant 2: 1000-1014.
  • Kong, Y., G. Zhou, U. Avci, X. Gu, C. Jones, Y. Yin, Y. Xu and M.G. Hahn. 2009. Two poplar glycosyltransferase genes, PdGATL1.1 and PdGATL1.2, are functional orthologs to PARVUS/AtGATL1 in Arabidopsis. Molec. Plant 2: 1040-1051.
  • Rao, Y., T. Buskas, A. Albert, M.A. O'Neill, M.G. Hahn and G.-J. Boons. 2008. Synthesis and immunological properties of a tetrasaccharide portion of the B-side chain of rhamnogalacturonan II (RG-II). ChemBioChem 9: 381-388.
  • Cavalier, D.M., O. Lerouxel, L. Neumetzler, K. Yamauchi, A. Reinecke, G. Freshour, M.G. Hahn, I. Burgert, M. Pauly, N. Raikhel, and K. Keegstra. 2008. Disrupting two Arabidopsis thaliana xylosyltransferase genes results in plants deficient in xyloglucan, a major primary cell wall component. Plant Cell 20:1519-1537.
  • Young, R.E., H. MacFarlane, M.G. Hahn, T.L. Western, G.W. Haughn and A.L. Samuels. 2008. Analysis of the Golgi apparatus in Arabidopsis seed coat cells during polarized secretion of pectin-rich mucilage. Plant Cell 20:1623-1638.
  • Zabotina, O., M. van de Ven, G. Freshour, G. Drakakaki, D. Cavalier, M.G. Hahn, K. Keegstra and N.V. Raikhel. 2008. Arabidopsis XXT5 gene encodes a putative α 1,6-xylosyltransferase that is involved in xyloglucan biosynthesis. Plant J. 56: 101-115.