Location: Bioenergy ResearchTitle: Integrated phospholipidomics and transcriptomics analysis of Saccharomyces cerevisiae with enhanced tolerance to a mixture of acetic acid, furfural, and phenol) Author
Submitted to: Omics - A Journal Of Integrative Biology
Publication Type: Peer reviewed journal
Publication Acceptance Date: 3/26/2012
Publication Date: 4/26/2012
Publication URL: http://handle.nal.usda.gov/10113/62012
Citation: Yang, J., Ding, M., Li, B., Liu, Z., Wang, X., Yuan, Y. 2012. Integrated phospholipidomics and transcriptomics analysis of Saccharomyces cerevisiae with enhanced tolerance to a mixture of acetic acid, furfural, and phenol. Omics: A Journal of Integrative Biology. 16(7-8):374-386. Interpretive Summary: Inhibitory compounds generated by pretreatment of biomass can repress microbial growth and subsequent fermentation. Overcoming the inhibitory effects and development of tolerant ethanol producing yeast strains are necessary to support the sustainable production of biofuels from lignocellulose rich agricultural residues and energy crops. The current research examined how yeasts respond and adapt genetically and physically to stresses imposed by exposure to compounds commonly found in pretreated biomass. This research discovered tolerant yeasts changed their cellular fatty acid compositions which was correlated with changes in expression of genes involved in lipid metabolism. The comparative study also characterized significant difference between the tolerant yeast and its parental strain. Findings of this research provide insight into mechanisms of yeast tolerance to inhibitors that will aid the development of more inhibitor-tolerant strains for lignocellulosic biofuels production.
Technical Abstract: A mixture of acetic acid, furfural and phenol (AFP), three representative lignocellulose derived inhibitors, significantly inhibited the growth and bioethanol production of Saccharomyces cerevisiae. In order to uncover mechanisms behind the enhanced tolerance of an inhibitor-tolerant S.cerevisiae strain (T), we measured the plasma membrane properties, which significantly influence cellular adaptation to inhibitors, of T strain and its parental strain (P) with/without AFP treatment. We integrated data obtained from multi-statistics-assisted phospholipidomics and parallel transcriptomics by using LC–tandem MS and microarray analysis. With the AFP treatment, the transcriptional changes of fatty acid metabolic genes showed strong correlation with the increase of fatty-acyl-chain length of phosphatidylcholine (PC) and phosphatidylinositol (PI). This suggests a possible compensatory mechanism to cope with the increase of plasma membrane permeability and fluidity in both strains. Moreover, the absence of phosphatidylserine (PS) and phosphatidylethanolamine (PE) species from the most variable phospholipid species group was a discriminative feature of T strain. This resulted from the decrease of CHO1 and increase of CHO2 levels of T strain upon AFP treatment. These novel findings reveal that the coordinated transcription and phospholipid composition changes contribute to the increased robustness of the T strain and highlight potential metabolic engineering targets for mutant(s) with higher tolerance.