Construction of a recombinant autolytic wine yeast strain overexpressing the csc1‐1 allele

Abstract

During the aging step of sparkling wines and wines aged on lees, yeast cells kept in contact with the wine finally die and undergo autolysis, releasing cellular compounds with a positive effect on the wine quality. In view of the interest of autolysis for wine properties, biotechnologists have tried to improve autolytic yield during winemaking. In this work we used genetic engineering techniques to construct an autolytic industrial strain by expressing the csc1-1 allele from the RDN1 locus. The expression of this mutant allele, that causes a "constitutive in autophagy phenotype," resulted in accelerated autolysis of the recombinant strain. Although autophagic phenotype due to csc1-1 expression has been reported to require the mutant allele in multicopy, autolytic acceleration was achieved by expressing only one or two copies of the gene under the control of the constitutive promotor pTDH3. The acceleration of autolysis together with the unaltered fermentative capacity, strongly supported the overexpression of csc1-1 allele as a strategy to obtain wines with aged-like properties in a shortened time.

Systematic Identification of Yeast Proteins Extracted into Model Wine during Aging on the Yeast Lees

“…There is great interest in correlating potential interactions between mannoproteins and tannins in red wines with desirable changes in sensory characteristics, for example, astringency, texture, and mouthfeel − . Genetic interventions have also been reported that increase the release of mannoproteins in laboratory and industrial strains of S. cerevisiae ,− .…”

Truth in wine yeast

“…Other authors addressed the expression of extracellular hydrolytic enzymes from different origins, mostly to help the release of primary aroma compounds from odourless precursors and improve mechanical properties of the juice and mass to ease extraction processing (Pérez‐González et al ., 1993 ; Ganga et al ., 1999 ). Another common type of genetic modification was changing the expression levels of S. cerevisiae genes to achieve improvements in secondary aroma, autolysis, or mannoprotein release (Lilly et al ., 2000 ; Lilly et al ., 2006 ; Tabera et al ., 2006 ; Cebollero et al ., 2009 ; González‐Ramos et al ., 2009 ). But none of these efforts directly led to new commercial starter cultures.…”

An event-specific method for the detection and quantification of ML01, a genetically modified Saccharomyces cerevisiae wine strain, using quantitative PCR

“…In the past, the growing demand for wine strains with specific technological characteristics led to the proposal of numerous engineered strains for various applications but, despite this, only a few cases have passed the laboratory scale (Pérez-González et al, 1993;González-Candelas et al, 1995, 2000Michnick et al, 1997;Schoeman et al, 1999;Lilly et al, 2000;Swiegers et al, 2007;Herrero et al, 2008;Cebollero et al, 2009). In almost all cases they are transgenic strains where one or more genetic determinants, derived from different organisms, were inserted into the host S. cerevisiae genome.…”