Role of Unsaturated Lipid and Ergosterol in Ethanol Tolerance of Model Yeast Biomembranes

Handle URI:
http://hdl.handle.net/10754/555601
Title:
Role of Unsaturated Lipid and Ergosterol in Ethanol Tolerance of Model Yeast Biomembranes
Authors:
Vanegas, Juan M.; Contreras, Maria F.; Faller, Roland; Longo, Marjorie L.
Abstract:
We present a combined atomic force microscopy and fluorescence microscopy study of the behavior of a ternary supported lipid bilayer system containing a saturated lipid (DPPC), an unsaturated lipid (DOPC), and ergosterol in the presence of high ethanol (20 vol %). We find that the fluorescent probe Texas Red DHPE preferentially partitions into the ethanol-induced interdigitated phase, which allows the use of fluorescence imaging to investigate the phase behavior of the system. Atomic force microscopy and fluorescence images of samples with the same lipid mixture show good agreement in sample morphology and area fractions of the observed phases. Using area fractions obtained from fluorescence images over a broad range of compositions, we constructed a phase diagram of the DPPC/DOPC/ergosterol system at 20 vol % ethanol. The phase diagram clearly shows that increasing unsaturated lipid and/or ergosterol protects the membrane by preventing the formation of the interdigitated phase. This result supports the hypothesis that yeast cells increase ergosterol and unsaturated lipid content to prevent interdigitation and maintain an optimal membrane thickness as ethanol concentration increases during anaerobic fermentations. Changes in plasma membrane composition provide an important survival factor for yeast cells to deter ethanol toxicity.
KAUST Department:
Biological and Environmental Sciences and Engineering (BESE) Division
Citation:
Role of Unsaturated Lipid and Ergosterol in Ethanol Tolerance of Model Yeast Biomembranes 2012, 102 (3):507 Biophysical Journal
Journal:
Biophysical Journal
Issue Date:
7-Feb-2012
DOI:
10.1016/j.bpj.2011.12.038
PubMed ID:
22325273
PubMed Central ID:
PMC3274781
Type:
Article
ISSN:
00063495
Additional Links:
http://linkinghub.elsevier.com/retrieve/pii/S0006349511054695
Appears in Collections:
Articles; Biological and Environmental Sciences and Engineering (BESE) Division; Biological and Environmental Sciences and Engineering (BESE) Division

Full metadata record

DC FieldValue Language
dc.contributor.authorVanegas, Juan M.en
dc.contributor.authorContreras, Maria F.en
dc.contributor.authorFaller, Rolanden
dc.contributor.authorLongo, Marjorie L.en
dc.date.accessioned2015-05-24T14:20:50Zen
dc.date.available2015-05-24T14:20:50Zen
dc.date.issued2012-02-07en
dc.identifier.citationRole of Unsaturated Lipid and Ergosterol in Ethanol Tolerance of Model Yeast Biomembranes 2012, 102 (3):507 Biophysical Journalen
dc.identifier.issn00063495en
dc.identifier.pmid22325273en
dc.identifier.doi10.1016/j.bpj.2011.12.038en
dc.identifier.urihttp://hdl.handle.net/10754/555601en
dc.description.abstractWe present a combined atomic force microscopy and fluorescence microscopy study of the behavior of a ternary supported lipid bilayer system containing a saturated lipid (DPPC), an unsaturated lipid (DOPC), and ergosterol in the presence of high ethanol (20 vol %). We find that the fluorescent probe Texas Red DHPE preferentially partitions into the ethanol-induced interdigitated phase, which allows the use of fluorescence imaging to investigate the phase behavior of the system. Atomic force microscopy and fluorescence images of samples with the same lipid mixture show good agreement in sample morphology and area fractions of the observed phases. Using area fractions obtained from fluorescence images over a broad range of compositions, we constructed a phase diagram of the DPPC/DOPC/ergosterol system at 20 vol % ethanol. The phase diagram clearly shows that increasing unsaturated lipid and/or ergosterol protects the membrane by preventing the formation of the interdigitated phase. This result supports the hypothesis that yeast cells increase ergosterol and unsaturated lipid content to prevent interdigitation and maintain an optimal membrane thickness as ethanol concentration increases during anaerobic fermentations. Changes in plasma membrane composition provide an important survival factor for yeast cells to deter ethanol toxicity.en
dc.relation.urlhttp://linkinghub.elsevier.com/retrieve/pii/S0006349511054695en
dc.rightsArchived with thanks to Biophysical Journal http://www.elsevier.com/open-access/userlicense/1.0/en
dc.titleRole of Unsaturated Lipid and Ergosterol in Ethanol Tolerance of Model Yeast Biomembranesen
dc.typeArticleen
dc.contributor.departmentBiological and Environmental Sciences and Engineering (BESE) Divisionen
dc.identifier.journalBiophysical Journalen
dc.identifier.pmcidPMC3274781en
dc.eprint.versionPublisher's Version/PDFen
dc.contributor.institutionBiophysics Graduate Group, College of Biological Sciences, University of California, Davis, Californiaen
dc.contributor.institutionDepartment of Chemical Engineering and Materials Science, University of California, Davis, Californiaen
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