Rapid identification of Saccharomyces cerevisiae, Zygosaccharomyces bailii and Zygosaccharomyces rouxii.

Most strains of Saccharomyces cerevisiae, Zygosaccharomyces bailii and Zygosaccharomyces rouxii have been found to contain plasmid DNA. The sequences of the plasmids from these three yeasts are known to be different. We have used two primers within the plasmid from each yeast species in a multiplex polymerase chain reaction (PCR) to discriminate between these three yeasts. The primers were designed to give easily distinguishable fragment sizes when run on a simple agarose gel. Due to the sensitivity of PCR, crude cells can be used with no need to isolate DNA. The method is rapid when compared with current methods.