Stronger Membranes Help Yeast Tolerate Bioenergy Production Chemicals

Incorporating sterols in the outer membrane of Yarrowia lipolytica makes it significantly more tolerant of ionic liquids.

The Science

Creating biofuels and other products from plant material is a complex process. Breaking down plant cells requires chemicals, among other things. Organic solvents like ionic liquids (ILs) represent one example. Scientists also need microbes such as yeast to convert the resulting plant material into biofuels and biochemicals. However, ILs often keep microbes from growing. Taken together, ILs inhibit cell growth by fluidizing the membrane and inflicting lateral pressures that destroy cellular homeostasis. Now, scientists have learned how one strain of yeast, Yarrowia lipolytica, strengthens its membranes. With stronger membranes, this yeast can better withstand ILs.

The Impact

This study produced the microorganism most tolerant to ILs. Robustness is an important production phenotype for any industrial microbial catalyst to acquire but it is complex and difficult to engineer. Researchers discovered that sterols play a key role for enhancing exceptional IL tolerance in Y. lipolytica. This study provides a better understanding of exceptional robustness of Y. lipolytica that can be potentially harnessed as a microbial manufacturing platform for production of fuels and chemicals in organic solvents.

Principal Investigator

Cong T. Trinh
University of Tennessee–Knoxville
[email protected]

References

Walker, C., S. Ryu, and C. T. Trinh. 2019. “Exceptional Solvent Tolerance in Yarrowia lipolytica is Enhanced by Sterols.,Metabolic Engineering 54(C), 83–95. DOI:10.1016/j.ymben.2019.03.003.