Membrane engineering for reduced acetic acid stress: insights from Zygosaccharomyces bailii
Konferensbidrag (offentliggjort, men ej förlagsutgivet), 2015

The high concentration of acetic acid released during pretreatment of lignocellulose raw material is a major obstacle to the microbial production of bio-based products. Acetic acid enters the cell mainly by passive diffusion across the plasma membrane and inhibits yeast by mechanisms such as reduction of intracellular pH, accumulation of the acetate anion, and by signaling effects triggering cell death. Through extensive characterization of the acetic acid tolerant yeast Zygosaccharomyces bailii, we have identified the cell membrane as a target for strain engineering with potential to increase acetic acid tolerance in Saccharomyces cerevisiae. We propose membrane permeability as a key component for Z. bailii’s acetic acid tolerance. We have previously shown that Z. bailii has a unique ability to remodel its plasma membrane upon acetic acid stress, to strongly increase its fraction of complex sphingolipids, at the expense of a drastic reduction of glycerophospholipids1. Here we further demonstrate the involvement of complex sphingolipids in acetic acid tolerance by decreasing sphingolipid synthesis using the drug myriocin, and characterize the acetic acid tolerance in terms of growth and intracellular pH. Furthermore we show the impact of complex sphingolipids on membrane physical properties using in silico membrane simulations. Ongoing membrane engineering of S. cerevisiae can potentially give additional strength to our findings. References 1 Lindberg et al. (2013), Lipidomic Profiling of Saccharomyces cerevisiae and Zygosaccharomyces bailii Reveals Critical Changes in Lipid Composition in Response to Acetic Acid Stress, PLoS One 8: e73936.

tolerance

sphingolipids

molecular dynamic simulations

acetic acid

Författare

Lina Lindahl

Chalmers, Biologi och bioteknik, Industriell bioteknik

Aline X S Santos

Samuel Genheden

Leif A Eriksson

Göteborgs universitet

Howard Riezman

Lisbeth Olsson

Chalmers, Biologi och bioteknik, Industriell bioteknik

Maurizio Bettiga

Chalmers, Biologi och bioteknik, Industriell bioteknik

Oral presentation at 12th Yeast Lipid Conference, May 20-22 2015, Ghent, Belgium

Ämneskategorier

Biokemi och molekylärbiologi

Styrkeområden

Energi

Livsvetenskaper och teknik