The effect of osmotic pressure on the membrane fluidity of Saccharomyces cerevisiae at different physiological temperatures

• Published in: Applied microbiology and biotechnology Vol. 56; no. 1-2; pp. 249 - 254
• Main Authors: LAROCHE, C, BENEY, L, MARECHAL, P. A, GERVAIS, P
• Format: Journal Article
• Language: English
• Published: Berlin Springer 01.07.2001; Springer Nature B.V; Springer Verlag
• Subjects: 1,6-diphenyl-1,3,5-hexatriene; Biological and medical sciences; Biotechnology; Chemical and Process Engineering; Engineering Sciences; Fundamental and applied biological sciences. Psychology; Life Sciences; Membrane Fluidity; Membrane Proteins - chemistry; Microbiology; Miscellaneous; Molecular Conformation; Mycology; Osmosis; Osmotic Pressure; Phase transitions; Phospholipids - chemistry; Saccharomyces cerevisiae; Saccharomyces cerevisiae - physiology; Temperature; Yeast; Temperature; Yeast; Industrial application; Dehydration; Fungi; Osmotic shock; Fluidity; Plasma membrane; Ascomycetes; Osmotic pressure; Saccharomyces cerevisiae; Viability; Thallophyta; Conformation
• ISSN: 0175-7598; 1432-0614
• DOI: 10.1007/s002530000583

Membrane fluidity in whole cells of Saccharomyces cerevisiae W303-1A was estimated from fluorescence polarization measurements using the membrane probe, 1,6-diphenyl-1,3,5-hexatriene, over a wide range of temperatures (6-35 degrees C) and at seven levels of osmotic pressure between 1.38 MPa and 133.1 MPa. An increase in phase transition temperatures was observed with increasing osmotic pressure. At 1.38 MPa, a phase transition temperature of 12 +/- 2 degrees C was observed, which increased to 17 +/- 4 degrees C at 43.7 MPa, 21+/- 7 degrees C at 61.8 MPa, and 24 +/- 9 degrees C at an osmotic pressure of 133.1 MPa. From these results we infer that, with increases in osmotic pressure, the change in phospholipid conformation occurs over a larger temperature range. These results allow the representation of membrane fluidity as a function of temperature and osmotic pressure. Osmotic shocks were applied at two levels of osmotic pressure and at nine temperatures, in order to relate membrane conformation to cell viability.