Location: Bioenergy Research
2021 Annual Report
Accomplishments
1. Transposable element genes impact yeast adaptation to toxic chemicals. Conventional industrial yeast is susceptible to stresses (such as chemicals) that occur in the cellulose-to-fuels fermentation process. In practice, yeast can adapt to have increased robustness, but mechanisms of adaptation are poorly understood. ARS scientists at Peoria, Illinois, discovered multiple transposable elements (TE; i.e. “movable genes) associated with adapted yeast tolerance against the major toxic chemicals that arise when biomas is used to make bioproducts. Genome sequence analysis conducted in collaboration with a scientist at Iowa State University produced evidence of specific changes caused by TEs. This new knowledge points to genes and metabolic strategies useful for continued development of more robust and efficient industrial strains. These research efforts aid production of sustainable energy for a cleaner environment.
2. Improved tool for engineering yeast. Fluorescent markers are essential for studying cellular proteins. They make it possible to see a protein’s location in the cell and investigate the dynamics of how much of, and when, a protein is made. A newer fluorescent protein, reported to have increased brightness and maturation time compared to other reporter proteins, is useful for analyzing proteins even when they are present in small amounts. ARS scientists at Peoria, Illinois, created a version of the protein that more than doubled its brightness in yeast. This improved sensor will allow scientists to visualize essential yeast proteins that are produced at very low levels. Improving the understanding of how cells control and regulate protein expression makes it easier to engineer yeast strains to produce fuels and chemicals. This research benefits scientists using Brewer’s yeast as a model organism and producers of renewable products seeking to optimize yields.
Review Publications
Liu, Z., Huang, X. 2020. A glimpse of potential transposable element impact on adaptation of the industrial yeast Saccharomyces cerevisiae. Federation of European Microbiological Societies Yeast Research. 20(6). Article foaa043. https://doi.org/10.1093/femsyr/foaa043.
Mertens, J.A., Skory, C.D., Nichols, N.N., Hector, R.E. 2020. Impact of stress-response related transcription factor overexpression on lignocellulosic inhibitor tolerance of Saccharomyces cerevisiae environmental isolates. Biotechnology Progress. 37(2). Article e3094. https://doi.org/10.1002/btpr.3094.
Jimenez, D., Wang, Y., de Mares, M., Cortes-Tolalpa, L., Mertens, J.A., Hector, R.E., Lin, J., Johnson, J., Lipzen, A., Barry, K., Mondo, S.J., Grigoriev, I.V., Nichols, N.N., Van Elsas, J.D. 2019. Defining the eco-enzymological role of the fungal strain Coniochaeta sp. 2T2.1 in a tripartite lignocellulolytic microbial consortium. FEMS Microbiology Ecology. 96(1). Article fiz186. https://doi.org/10.1093/femsec/fiz186.
Nichols, N.N., Hector, R.E., Mertens, J.A., Frazer, S.E. 2020. Abatement of inhibitors in recycled process water from biomass fermentations relieves inhibition of a Saccharomyces cerevisiae penthose phosphate pathway mutant. Fermentation. 6(4). Article 107. https://doi.org/10.3390/fermentation6040107.