RT Journal Article SR Electronic T1 Malolactic Fermentation in Grape Musts by a Genetically Engineered Strain of Saccharomyces cerevisiae JF American Journal of Enology and Viticulture JO Am J Enol Vitic. FD American Society for Enology and Viticulture SP 193 OP 197 DO 10.5344/ajev.1997.48.2.193 VO 48 IS 2 A1 H. Volschenk A1 M. Viljoen A1 J. Grobler A1 F. Bauer A1 A. Lonvaud-Funel A1 M. Denayrolles A1 R. E. Subden A1 H. J. J. Van Vuuren YR 1997 UL http://www.ajevonline.org/content/48/2/193.abstract AB Malate enters Saccharomyces cerevisiae by simple diffusion. Due to the lack of a malate transporter and the low affinity of the S. cerevisiae malic enzyme, this yeast is unable to degrade malate efficiently. We have constructed a malolactic yeast strain by co-expressing the malate permease gene (mae1) of the fission yeast Schizosaccharomyces pombe and the Lactococcus lactis malolactic gene (mleS) in S. cerevisiae. The recombinant strain of S. cerevisiae transported malate and actively metabolized malate to lactate within three days in Cabernet Sauvignon and Shiraz grape musts at 20°C. The malolactic fermentation in Chardonnay grape must was completed within seven days at 15°C. The efficient degradation of malate in grape musts is important to wineries and the availability of malolactic yeasts will allow the early application of cellar operations for storage and aging of wine.