Michael R. Gretz

Michael R. Gretz


  • Professor, Biological Sciences
  • Director, Chemical Advanced Resolution Methods Laboratory
  • PhD, Arizona State University

Research Descriptions

Our work is centered on the cell wall and associated extracellular polymers of algae. We are interested in what these algal extracellular matrices can tell us about: 1) the evolution of the land plant cell wall, 2) the unique characteristics that allow for life in aquatic habitats, 3) the interactions within complex biofilms, including the heterotropic utilization of complex macromolecules, and 4) the biomineralization processes (ex. silica and calcium carbonate) associated with these extracellular polymers.

What is the broader significance of our work? The characters of plant cell walls determine the properties of innumerable products we consume every day. Our work has potential impact on the pulping properties of wood, the mechanical properties of textile fibers, the health effects of dietary fiber, the efficiency of energy extraction from biofuels, among others. In aquatic ecosystems, algal extracellular polymers play a pivotal role in maintaining the integrity of biofilms. These biofilm consortia have high primary productivity and play a crucial role in many processes including regulating nutrient fluxes between terrestrial and aquatic ecosystems, flood mitigation, storm abatement, reduction of sediment from the water column, ground water recharge/purification, and maintaining stability of intertidal mudflats.

Research Interests

  • Algal Extracellular Polymers and Biocomposites - Regulation of Biogenesis

Recent Publications

  • Domozych, D.S.,. Lambiasse, L., Kiemle, S.N.. and Gretz, M.R. 2009. Structure and biochemistry of charophycean cell walls. II. Cell wall development and bipolar growth in the desmid Penium margaritaceum. Asymmetry in a symmetric world. Journal of Phycology (in press)
  • BBellinger, B.J., Underwood, G.J.C., Ziegler, S.E. and Gretz, M.R. 2009. The significance of diatom-derived polymers in carbon flow dynamics within estuarine biofilms determined through isotopic enrichment. Aquatic Microbial Ecology (in press).
  • Domozych, D.S., Serfis, A., Kiemle, S. and Gretz, M.R. 2007. The structure and biochemistry of charophycean cell walls. I. Pectins of Penium margaritaceum. Protoplasma 230:99-115.
  • Kiemle, S.N., Domozych, D.S. and Gretz, M.R. 2007. The exopolymers of desmids: Chemistry, structural analysis and implications in wetland biofilms. Phycologia 46:617-627.
  • Domozych, D.S., Elliot, L, Kiemle, S.N. and Gretz, M.R. 2007. Pleurotaenium trabecula, a desmid of wetland biofilms: The extracellular matrix and adhesion mechanisms. Journal of Phycology 43:1022-1038.
  • Abdullahi, A.S., Underwood, G.J.C., and Gretz, M.R. 2006. Extracellular matrix assembly in diatoms (Bacillariophyceae). V. Environmental effects on polysaccharide synthesis in the model diatom Phaeodactylum tricornutum. Journal of Phycology 42:363-378.
  • Apoya, M.D., Liang, Y., Underwood, G.J.C. and Gretz, M.R. 2006. Movement modalities and responses to environmental changes of the mudflat diatom Cylindrotheca closterium. Journal of Phycology 42:379-390.