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.
Recent Publications: 
  • Biswal, A.K., Z. Hao, S. Pattathil, X. Yang, K. Winkeler, C. Collins, S.S. Mohanty, E.A. Richardson, I. Gelineo-Albersheim, K. Hunt, D. Ryno, R.W. Sykes, G.B. Turner, A. Ziebell, E. Gjersing, W. Lukowitz, M.F. Davis, S.R. Decker, M.G. Hahn, and D. Mohnen.  2015.  Down-regulation of GAUT12 in Populus deltoides by RNA silencing results in reduced recalcitrance and increased growth in a woody biofuel feedstock.  Biotechnol. Biofuels, submitted for publication.  
  • De Souza, A.P., C.L.A. Kamei, A.F. Torres, S. Pattathil, M.G. Hahn, L.M. Trindade, and M.S. Buckeridge.  2015.  How cell wall complexity influences saccharification efficiency in Miscanthus sinensis.  J. Exp. Bot., submitted for publication.  
  • Pattathil, S., M.G. Hahn, B.E. Dale, and S.P.S. Chundawat.  2015.  Using glycome profiling to understand plant cell wall recalcitrance to deconstruction.  J. Exp. Bot., submitted for publication.  
  • Srivastava, A.C., F. Chen, T. Ray, S. Pattathil, U. Avci, H. Li, J.S. Miller, D.V. Huhman, M. Bedair, C.E. Wyman, L.W Sumner, M.G Hahn, R.A Dixon, E.B Blancaflor, and Y. Tang.  2015.  Repression of folypolyglutamate synthetase alters lignin composition and improves cell wall digestibility in Arabidopsis.  J. Exp. Bot., submitted for publication.
  • Kong, Y., M.J. Peña, X. Li, L. Renna, S.T. Tuomivaara, S. Pattathil, F. Brandizzi, U. Avci, M.G. Hahn, W.S. York, A.G. Darvill, W.-D. Reiter and M.A. O’Neill.  2015.  Disfunctional xyloglucan biosynthesis leads to dwarfism in Arabidopsis.  Plant Physiology, in press.  
  • Trajano, H.L., S. Pattathil, B.A. Tomkins, T.J. Tschalplinski, M.G. Hahn, G.J. Van Berkel and C.E. Wyman.  2015.  Xylan hydrolysis in Populus trichocarpa x P. deltoides and model substrates during hydrothermal pretreatment.  Bioresource Technology 179: 202-210.
  • Muszyński, A., M.A. O’Neill, E. Ramasamy, S. Pattathil, U. Avci, M.J. Peña, M. Libault, M.S. Hossain, L. Brechenmacher, W.S. York, R.M. Barbosa, M.G. Hahn, G. Stacey and R.W. Carlson.  2014.  The pectic and hemicellulosic polysaccharides present in the cell walls of soybean roots and root hairs are not identical.  Glycobiology, submitted for publication.
  • Tan, L., Y. Pu, S. Pattathil, U. Avci, J. Qian, A. Arter, L. Chen, M. Hahn, A. Ragauskas and M. Kieliszewski.  2014.  Changes in cell wall properties coincide with overexpression of extensin fusion proteins in suspension cultured tobacco cells.  PLoS One 9(12): e115906 (DOI:10.1371/journal.pone.0115906).  
  • Izquierdo, J.A., S. Pattathil, A. Guseva, M.G. Hahn and L.R. Lynd.  2014.  Comparative analysis of the ability of Clostridium clariflavum strains and Clostridium thermocellum to utilize hemicellulose and unpretreated plant material.  Biotechnol. Biofuels 7: 136 (DOI: 10.1186/s13068-014-0136-4).  
  • Chung, D., S. Pattathil, A.K. Biswal, M.G. Hahn, D. Mohnen, and J. Westpheling.  2014.  Deletion of a gene cluster encoding pectin degrading enzymes in Caldicellulosiruptor bescii reveals an important role for pectin in plant biomass recalcitrance.  Biotechnol. Biofuels 7: 147 (DOI:10.1186/s13068-014-0147-1).
  • Socha, A.M., R. Parthasarathi, J. Shi, S. Pattathil, D. Whyte, M. Bergerson, S. Venkatachalam, M.G. Hahn, B.A. Simmons and S. Singh.  2014.  Efficient biomass pretreatment using ionic liquids derived from lignin and hemicellulose.  Proc. Natl. Acad. Sci. USA  111: E3587-E3595 (DOI: 10.1073/pnas.1405685111). 
  • Hao, Z., U. Avci, L. Tan, X. Zhu, J. Glushka, S. Pattathil, S. Eberhard, T. Sholes, G. Rothstein, W. Lukowitz, R. Orlando, M.G. Hahn and D. Mohnen.  2014.  Loss of Arabidopsis GAUT12/IRX8 causes anther indehiscence and leads to reduced G lignin associated with altered matrix polysaccharide deposition.  Front. Plant Sci. 5: 357 (DOI: 10.3389/fpls.2014.00357).
  • Li, M., S. Pattathil, M.G. Hahn and D.B. Hodge.  2014.  Identification of features associated with plant cell wall recalcitrance to pretreatment by alkaline hydrogen peroxide in diverse bioenergy feedstocks using glycome profiling.  RSC Advances 4: 17282-17292 (DOI: 10.1039/C4RA00824C).  
  • Li, H., S. Pattathil, M.B. Foston, S.-Y. Ding, R. Kumar, X. Gao, A. Mittal, J.M. Yarbrough, M.E. Himmel, A.J. Ragauskas, M.G. Hahn, and C.E. Wyman.  2014.  Agave proves to be a low recalcitrant lignocellulosic feedstock for biofuels production on semi-arid lands.  Biotechnol. Biofuels 7: 50 (DOI:10.1186/1754-6834-7-50).  
  • Liu, T., D.L. Williams, S. Pattathil, M.G. Hahn, M. Li and D.B. Hodge.  2014.  Coupling alkaline pre-extraction with alkaline-oxidative post-treatment of corn stover to enhance enzymatic hydrolysis and fermentability.  Biotechnol. Biofuels 7: 48 (DOI:10.1186/1754-6834-7-48).  
  • Yu, L., D. Shi, J. Li, Y. Kong, Y. Yu, G. Chai, R. Hu1, J. Wang, M.G. Hahn and G. Zhou.  2014.  CELLULOSE SYNTHASE-LIKE A2, a glucomannan synthase, is involved in maintaining adherent mucilage structure in Arabidopsis seed.  Plant Physiology 164: 1842-1856.  
  • Edwards, M.C., T. Williams, S. Pattathil, M.G. Hahn and J. Doran-Peterson.  2014.  Replacing a suite of commercial pectinases with a single enzyme, pectate lyase B, in Saccharomyces cerevisiae fermentations of cull peaches.  J. Ind. Microbiol. Biotechnol. 41: 679-686 (DOI 10.1007/s10295-013-1394-z).
  • 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.  Biotechnol. Biofuels 7: 11 (DOI:10.1186/1754-6834-7-11).  
  • 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., S4: 004 (DOI:10.4172/2155-6199.S4-004).  
  • 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.