Erg6 gene is essential for stress adaptation in Kluyveromyces lactis

• Published in: FEMS microbiology letters Vol. 365; no. 23; pp. 1 - 8
• Main Authors: Konecna, Alexandra, Toth Hervay, Nora, Bencova, Alexandra, Morvova, Jr, Marcela, Sikurova, Libusa, Jancikova, Iva, Gaskova, Dana, Gbelska, Yvetta
• Format: Journal Article
• Language: English
• Published: England Oxford University Press 01.12.2018
• Subjects: Adaptation (Physiology); Cell walls; ERG6 gene; Fluidity; Gene deletion; Genetic aspects; Glycerol; Glycerol-3-phosphate dehydrogenase; Hyperpolarization; Kluyveromyces lactis; Lipid composition; Lipids; Membrane fluidity; Membrane proteins; Membranes; Microbiology; Mutants; NAD; Organic acids; Phenotypes; Physiological aspects; Plasma; Statistical analysis; Stress (Physiology); Tunicamycin; Yeast; Yeast fungi; Slovakia
• ISSN: 1574-6968; 0378-1097; 1574-6968
• DOI: 10.1093/femsle/fny265

We investigated the effect of Kluyveromyces lactis ERG6 gene deletion on plasma membrane function and showed increased susceptibility of mutant cells to salt stress, cationic drugs and weak organic acids. Contrary to Saccharomyces cerevisiae, Klerg6 mutant cells exhibited increased tolerance to tunicamycin. The content of cell wall polysacharides did not significantly vary between wild-type and mutant cells. Although the expression of the NAD+-dependent glycerol 3-phosphate dehydrogenase (KlGPD1) in the Klerg6 mutant cells was only half of that in the parental strain, it was induced in the presence of calcofluor white. Also, cells exposed to this drug accumulated glycerol. The absence of KlErg6p led to plasma membrane hyperpolarization but had no statistically significant influence on the plasma membrane fluidity. We propose that the phenotype of Klerg6 mutant cells to a large extent was a result of the reduced activity of specific plasma membrane proteins that require proper lipid composition for full activity.