Unknown,Transcriptomics,Genomics,Proteomics

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Comparative transcriptome analysis between an original and a recombinant wine yeast strain defective for KNR4/SMI1

ABSTRACT: EKD-13 is among the recently developed mannoprotein overproducing strains. It is a recombinant derivative of the well known EC1118 commercial strain, in which the ORF of all the alleles of KNR4/SMI1 was replaced by different integration cassettes. Lack of Knr4p resulted in a negligible impairment in fermentation kinetics and a net reduction in bentonite requirements to attain complete protein stabilization of white wines made out of natural grape must. In order to improve the technological characterization of this strain, and to better understand the mechanisms underlying mannoprotein oversecretion, we have analyzed kinetics of mannoprotein release and autolysis during fermentation and aging, and we have performed a genome wide expression analysis in two different steps of the fermentation process. The results give some additional clues on KNR4 function in S. cerevisiae as well as on the best application conditions for this recombinant strain. A comparative transcriptome analysis between the S. cerevisiae recombinant strain (EKD-13) defective for KNR4/SMI1 and the wild-type strain (EC1118) was implemented. At every step of the fermentation (mid-exponential growth phase of fermentation advancement as 10 g of released CO2 and stationary-growth phase as 70 g of CO2 released) a recombinant and a WT yeast samples are put on a slide. There are three biological replicates that are labeled in dye-switch way (sometimes called biological dye-swap) for each step of fermentation leading to 3 independent intensity values for each gene (spots) on the microarrays. This experimental design minimizes the intrinsic biological noise between identical culture conditions and the technical variations inherent to the DNA microarray technology. In summary, there are six samples, each corresponding to comparisons between independent fermentations of both strains.

ORGANISM(S): Saccharomyces cerevisiae

SUBMITTER: Vanessa Penacho

PROVIDER: E-GEOD-26965 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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Comparative transcriptome analysis between an original and a recombinant wine yeast strain defective for KNR4/SMI1

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