The influence of growth conditions on MALDI-TOF MS spectra of winemaking yeast: implications for industry applications.

Abstract Previous studies have shown MALDI-TOF MS to be a powerful tool in wine yeast identification and potential prediction of application. However, it is also established that substrate composition influences protein expression , but the degree to which this may affect MALDI-TOF spectra (and analytical results thereof) has not been fully explored. To further inform assay optimisation, the influence on MALDI-TOF spectra was determined using eight Saccharomyces strains of diverse origins cultivated on grape juices from Pinot Noir and Chardonnay varieties, synthetic grape juice, and laboratory-grade artificial culture media (YPD broth and agar). Our results demonstrated significant influences of culture media on strain MALDI-TOF spectra. Yeast culture on YPD agar is recommended for taxonomic studies, with YPD broth culture of S. cerevisiae offering improved intra-subspecific differentiation Furthermore, our data supported a correlation between MALDI spectra and the potential industrial application of individual yeast strains.