A new methodology to obtain wine yeast strains overproducing mannoproteins.
Yeast mannoproteins are highly glycosylated proteins that are covalently bound to the beta-1,3-glucan present in the yeast cell wall. Among their outstanding enological properties, yeast mannoproteins contribute to several aspects of wine quality by protecting against protein haze, reducing astringency, retaining aroma compounds and stimulating growth of lactic-acid bacteria. The development of a non-recombinant method to obtain enological yeast strains overproducing mannoproteins would therefore be very useful. Our previous experience on the genetic determinants of the release of these molecules by Saccharomyces cerevisiae has allowed us to propose a new methodology to isolate and characterize wine yeast that overproduce mannoproteins. The described methodology is based on the resistance of the killer 9 toxin produced by Williopsis saturnus, a feature linked to an altered biogenesis of the yeast cell wall.
Quirós
Manuel
M
Instituto de Ciencias de la Vid y del Vino (CSIC-UR-CAR), Complejo Científico Tecnológico, C/ Madre de Dios, 51, 26006 Logroño (La Rioja), Spain. mquiros@icvv.es
Gonzalez-Ramos
Daniel
D
Tabera
Laura
L
Gonzalez
Ramon
R
D002473:Cell Wall / Q000378:metabolism; D005285:Fermentation; D005800:Genes, Fungal; D055646:Killer Factors, Yeast / Q000235:genetics*; D008562:Membrane Glycoproteins / Q000096:biosynthesis* / Q000235:genetics; D009154:Mutation; D010641:Phenotype; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000096:biosynthesis* / Q000235:genetics; D055320:Williopsis / Q000378:metabolism*; D014920:Wine / Q000382:microbiology* / Q000592:standards
D055646:Killer Factors, Yeast; D008562:Membrane Glycoproteins; D029701:Saccharomyces cerevisiae Proteins; C025363:mannoproteins