Forever panting and forever growing: physiology of Saccharomyces cerevisiae at extremely low oxygen availability in the absence of ergosterol and unsaturated fatty acids

Author(s)

Vale da Costa, Bruno Labate ^{[1, 2]} ; Raghavendran, Vijayendran ^{[1, 3]} ; Mercier Franco, Luis Fernando ^{[4, 2]} ; Chaves Filho, Adriano de Britto ^[5] ; Yoshinaga, Marcos Yukio ^[5] ; Miyamoto, Sayuri ^[5] ; Basso, Thiago Olitta ^[2] ; Gombert, Andreas Karoly ^[1]

Affiliation

^[1] Univ Estadual Campinas, Sch Food Engn, Rua Monteiro Lobato 80, BR-13083862 Campinas, SP - Brazil

^[2] Univ Sao Paulo, Dept Chem Engn, Escola Politecn, Av Prof Lineu Prestes 580, BR-05424970 Sao Paulo, SP - Brazil

^[3] Univ Sheffield, Dept Mol Biol & Biotechnol, Western Bank, Firth Court, Sheffield S10 2TN, S Yorkshire - England

^[4] Univ Estadual Campinas, Sch Chem Engn, Av Albert Einstein 500, Campinas, SP - Brazil

^[5] Univ Sao Paulo, Inst Chem, Av Prof Lineu Prestes 748, BR-05508000 Sao Paulo - Brazil

• Document type: Journal article
• Source: FEMS Yeast Research; v. 19, n. 6 SEP 2019.
• Web of Science Citations: 1

Abstract

We sought to investigate how far the growth of Saccharomyces cerevisiae under full anaerobiosis is dependent on the widely used anaerobic growth factors (AGF) ergosterol and oleic acid. A continuous cultivation setup was employed and, even forcing ultrapure N-2 gas through an O-2 trap upstream of the bioreactor, neither cells from S. cerevisiae CEN.PK113-7D (a lab strain) nor from PE-2 (an industrial strain) washed out after an aerobic-to-anaerobic switch in the absence of AGF. S. cerevisiae PE-2 seemed to cope better than the laboratory strain with this extremely low O-2 availability, since it presented higher biomass yield, lower specific rates of glucose consumption and CO2 formation, and higher survival at low pH. Lipid (fatty acid and sterol) composition dramatically altered when cells were grown anaerobically without AGF: saturated fatty acid, squalene and lanosterol contents increased, when compared to either cells grown aerobically or anaerobically with AGF. We concluded that these lipid alterations negatively affect cell viability during exposure to low pH or high ethanol titers. (AU)

• FAPESP's process: 15/14109-0 - Fuel ethanol production by the fastest eukaryote on the planet
• Grantee: Andreas Karoly Gombert
• Support type: Regular Research Grants
• FAPESP's process: 18/17172-2 - How do fuel ethanol yeasts and contaminating lactic acid bacteria respond toward lignocellulosic-derived inhibitors?
• Grantee: Thiago Olitta Basso
• Support type: Regular Research Grants