My research program is based on the study of plant secondary metabolites or phytochemicals. I am interested in how plants use phytochemicals to interact with other organisms or defend themselves against environmental factors such as wounding and pathogen attack. We spend a lot of time isolating and analysing phytochemicals using various chromatographic techniques and bioassays. Our research activities can be divided into two categories: 1) Biosynthesis of Suberin and 2) Chemical Ecology of Phytochemicals. Each is briefly described below.
1) Biosynthesis of Suberin In response to wounding and other environmental stresses, the cells of plants exposed to the stress may be induced to form suberin. Suberin is the name given to a specific cell wall modification deposited in periderm, wound periderm, and endo- and exodermal cells that involves the biosynthesis of a poly(phenolic) domain (SPPD) within the cell wall as well as a poly(aliphatic) domain (SPAD) between the plasma membrane and the cell wall. The structure of suberin has undergone revision as new information about its chemical composition is revealed. We recently proposed a new structural model for potato tuber suberin, based on our studies as well as extensive literature reports. We have also developed a model to help understand the macromolecular assembly of the SPPD and have two current projects testing it. More recently, we have initiated a metabolite profiling project to better understand the changes in both primary and secondary metabolism that occur during suberization.
2) Chemical Ecology of Phytochemicals Many phytochemicals are biologically active and play a direct role in the interaction between a plant and its environment. In my lab we are investigating the potential of ginsenosides to act as allelochemicals and how different soilborne fungi respond to them in vitro.
Degrees and Institutions
BSc (Agriculture) University of Guelph, 1985
PhD (Biochemistry) University of Guelph, 1991
PDF, Washington State University, Institute for Biological Chemistry, 1991-93
Assistant Professor, Program in Chemistry, University of Northern BC, 1993-1998
At Western since 1998
Biology 2601A - Organismal Physiology
Boychuk, E.C., Smiley, J.T., Dahlhoff, E.P., Bernards. M.A., Rank, N.E., and Sinclair, B.J. (2015) Cold tolerance of the montane Sierra leaf beetle, Chrysomela aeneicollis. J. Insect Physiol. 81, 157-166.
Padilla-Reynaud, R., Simao-Beaunoir, A.-M., Lerat, S., Bernards, M.A., and Beaulieu, C. (2015) Suberin regulates the production of cellulytic enzymes in Streptomyces scabei, the causal agent of potato common scab. Microbes & Environment 30, 245-253.
Schmerk, C., Welander, P.V., Hamad, M.A., Bain, K.L., Bernards, M.A., Summons, R.E. and Valvano, M.A. (2015) Elucidation of the Burkholderia cenocepacia hopanoid biosynthesis pathway uncovers functions for conserved proteins in hopanoid-producing bacteria. Environmental Microbiology 17, 735-750
Cadieux, B, Vijayakumaran V, Bernards, M.A., McGavin, M.J. and Heinrichs, D.E. (2014) Role of lipase, from community-associated methicillin-resistant Staphylococcus aureus strain USA300, in hydrolyzing triglycerides into growth inhibitory free fatty acids. J. Bacteriol. 196, 4044-4056.
Williams, C.M., Nicolai, A., Ferguson, L.V., Bernards, M.A., Hellmann, J.J., and Sinclair, B.J. (2014) Cold hardiness and deacclimation of overwintering Papilio zelicaon pupae. Comparative Biochemistry and Physiology, Part A 178:51–58
Boufis, N., Majda, K-S., Zakia, D., Djamila, Z., Abdelkader, M., Bernards, M.A., Makhzoum, A., and Khelifi, L. (2014) Effects of growth regulators and types of culture media on somatic embryogenesis in date palm (Phoenix dactylifera L. cv. Degla Beida) Scientia Horticulturae 172:135-142.
Cadieux, B, Vijayakumaran V, Bernards, M.A., McGavin, M.J. and Heinrichs, D.E. (2014) Role of lipase, from community-associated methicillin-resistant Staphylococcus aureus strain USA300, in hydrolyzing triglycerides into growth inhibitory free fatty acids. J. Bacteriol.