Learmonth, Robert and Butcher, Brett A. (2007) OLE1 and HSP30 affect yeast membrane fluidity modulation during growth and in response to glucose. In: 23rd International Conference on Yeast Genetics and Molecular Biology, 1-6 Jul 2007, Melbourne, Australia.
Adaptation of yeasts to changing environments during growth, fermentation and bioprocessing requires rapid modulation of membrane fluidity. We studied fluidity modulation in S. cerevisiae FY1679-28c and its mutants lacking lipid desaturase ole1 or membrane-associated hsp30. We assessed relationships between fluidity and physiological parameters during aerobic and anaerobic batch culture, as well as membrane responses to glucose availability, determining progressive fluidity changes with fluorescent membrane probes. During batch growth the parent strain evidenced balanced relationships between membrane fluidity, phospholipid and fatty acyl composition, growth rate, glucose or ethanol consumption and viability. However the ole1 and hsp30 deletants appeared out of balance with less efficient metabolism (higher nutrient consumption), lower budding rates and lower viability. The ole defect was rectified by supplementation with C18:1 or C18:2. The hsp30 defect had particular impact over the transition at glucose exhaustion. The parent had negligible membrane fluidity response to glucose while the hsp30 and ole1 deletants both showed marked changes in fluidity on glucose addition above (0.5% w/v) or below (0.1%) the catabolite repression threshold. Thus membrane responses in the deletants were different to the parent strain, indicating that their fluidity regulation mechanisms were unbalanced by ablation of the activities of either of these membrane-associated proteins.
|Item Type:||Conference or Workshop Item (Commonwealth Reporting Category E) (Paper)|
|Additional Information:||Abstract only available.|
|Uncontrolled Keywords:||yeast, hsp30, ole1, membranes|
|Subjects:||290000 Engineering and Technology > 290100 Industrial Biotechnology and Food Sciences > 290101 Fermentation, Biotechnology and Industrial Microbiology
270000 Biological Sciences > 270300 Microbiology > 270306 Microbial Genetics
270000 Biological Sciences > 270100 Biochemistry and Cell Biology > 270104 Membrane Biology
|Depositing User:||Ms Debbie White|
|Date Deposited:||11 Oct 2007 01:19|
|Last Modified:||02 Jul 2013 22:48|
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