Effect of fatty acid supplementation on thermotropic behavior of membrane lipids and leucine transport in Saccharomyces cerevisiae.
An unsaturated fatty acid-requiring mutant (KD 115) of Saccharomyces cerevisiae shows altered phospholipid composition, transport behavior, and physical properties of membrane lipids when grown in the presence of different cis- and trans-unsaturated fatty acids. There is an increase in phosphatidyl ethanolamine content and a concomitant decrease in phosphatidyl choline content in the cells supplemented with trans-unsaturated fatty acids. The affinity for uptake of L-leucine is higher in the cis-unsaturated fatty acid-supplemented cells compared with the trans-unsaturated fatty acid-supplemented cells. The temperature-dependence of L-leucine uptake bears a reasonably good correlation with the thermotropic behavior of the membrane lipids as studied by the steady-state fluorescence polarization technique. The present findings are discussed in light of the importance of the lipid environment in modulating membrane-associated functions.
D001692:Biological Transport / Q000187:drug effects; D005231:Fatty Acids, Unsaturated / Q000378:metabolism / Q000494:pharmacology*; D005454:Fluorescence Polarization; D007930:Leucine / Q000378:metabolism*; D008560:Membrane Fluidity / Q000187:drug effects; D008563:Membrane Lipids / Q000378:metabolism*; D009154:Mutation; D010743:Phospholipids / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000378:metabolism; D013816:Thermodynamics
D005231:Fatty Acids, Unsaturated; D008563:Membrane Lipids; D010743:Phospholipids; D007930:Leucine