Comparative characterization of endo-polygalacturonase (Pgu1) from Saccharomyces cerevisiae and Saccharomyces paradoxus under winemaking conditions

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dc.contributor.authorEschstruth, A.en_ZA
dc.contributor.authorDivol, Benoiten_ZA
dc.date.accessioned2011-10-13T16:58:29Z
dc.date.available2011-10-13T16:58:29Z
dc.date.issued2011
dc.description.abstractWine strains of Saccharomyces cerevisiae have no to weak natural pectinase activity, despite their genetic ability to secrete an endo-polygalacturonase. The addition of external pectinase of fungal origin has therefore become a common step of winemaking in order to enhance the extraction of compounds located in the grape berry skins during maceration and to ease wine clarification after maturation. Recently, the strong pectinase activity of a wine strain of Saccharomyces paradoxus has been reported. In this study, the endo-polygalacturonase-encoding gene of S. paradoxus was sequenced and its activity was characterised, compared with that of S. cerevisiae and tested under winemaking conditions through overexpression of both genes individually in S. cerevisiae. A few differences in the amino acids sequences between the two proteins were revealed and the activity of the Pgu1 enzyme of S. paradoxus was shown to be weaker under winemaking conditions. Clear indicators of extracellular activity were observed in the wines made with both recombinant strains (i.e. enzyme activity in cell-free wine, higher methanol concentration and higher free-run wine), but the actual composition of the wines fermented with the mutants was only sparingly altered. Although unexpectedly found in lower concentrations in the latter wines, phenolic compounds were shown to be the most discriminatory components. Overexpressing the PGU1 gene of S. paradoxus or that of S. cerevisiae did not make much difference, showing that the higher activity of S. paradoxus strains under laboratory conditions could be due to a different regulation mechanism rather than to a different sequence of PGU1. © 2011 Springer-Verlag.
dc.description.versionArticle
dc.identifier.citationApplied Microbiology and Biotechnology
dc.identifier.citation91
dc.identifier.citation3
dc.identifier.citationhttp://www.scopus.com/inward/record.url?eid=2-s2.0-79960709492&partnerID=40&md5=5dbd9a4d5bb3412e884937ac77128615
dc.identifier.issn1757598
dc.identifier.other10.1007/s00253-011-3238-y
dc.identifier.urihttp://hdl.handle.net/10019.1/16746
dc.subjectEndo-polygalacturonase activity
dc.subjectPGU1
dc.subjectSaccharomyces paradoxus
dc.subjectWine
dc.subjectCell-free
dc.subjectEndo-polygalacturonase activity
dc.subjectExtracellular activity
dc.subjectGrape berry
dc.subjectLaboratory conditions
dc.subjectMethanol concentration
dc.subjectOver-expression
dc.subjectPectinases
dc.subjectPGU1
dc.subjectPhenolic compounds
dc.subjectRecombinant strains
dc.subjectRegulation mechanisms
dc.subjectS.cerevisiae
dc.subjectSaccharomyces
dc.subjectWine clarification
dc.subjectWine strains
dc.subjectAmino acids
dc.subjectFruits
dc.subjectGene encoding
dc.subjectMethanol
dc.subjectPhenols
dc.subjectWine
dc.subjectYeast
dc.subjectEnzyme activity
dc.subjectmethanol
dc.subjectpolygalacturonase
dc.subjectcomparative study
dc.subjectconcentration (composition)
dc.subjectdiscriminant analysis
dc.subjectenzyme activity
dc.subjectfermentation
dc.subjectgene expression
dc.subjectlaboratory method
dc.subjectmaturation
dc.subjectmethanol
dc.subjectmutation
dc.subjectprotein
dc.subjectrecombination
dc.subjectvine
dc.subjectyeast
dc.subjectamino acid sequence
dc.subjectarticle
dc.subjectenzyme activity
dc.subjectfungal gene
dc.subjectgene overexpression
dc.subjectnucleotide sequence
dc.subjectregulatory mechanism
dc.subjectSaccharomyces
dc.subjectSaccharomyces cerevisiae
dc.subjectSaccharomyces paradoxus
dc.subjectwine
dc.subjectwine industry
dc.subjectSaccharomyces cerevisiae
dc.subjectSaccharomyces paradoxus
dc.subjectVitaceae
dc.titleComparative characterization of endo-polygalacturonase (Pgu1) from Saccharomyces cerevisiae and Saccharomyces paradoxus under winemaking conditions
dc.typeArticle
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