A new putative Zygosaccharomyces yeast species isolated from traditional balsamic vinegar

Abstract

The taxonomic status and species number of the genus Zygosaccharomyces have rapidly changed in the last years. In this study, two new osmotolerant Zygosaccharomyces strains isolated from traditional balsamic vinegar, viz. ABT301 and ABT601, were investigated to elucidate their taxonomic relationships with Zygosaccharomyces rouxii species. A multi-gene sequence approach was employed, including regions of the rDNA repeat [5.8S, two internal transcribed spacers (ITS) and the 26S D1/D2 domain], COX2 mitochondrial gene and two nuclear genes (SOD2 and HIS3 ). Cloning and sequence analysis of 5.8S-ITS rDNA revealed that these strains bear an unusual polymorphism for this region. Three highly divergent 5.8S-ITS sequences were detected, one identical to Z. rouxii, the other two showing some relatedness to Z. mellis. Sequence and gene number polymorphism was also observed for the protein-encoding nuclear genes SOD2 and HIS3, as two copies for each gene different from those found in Z. rouxii were detected. Analysis of the D1/D2 26S domain showed that ABT301 and ABT601 have only one type of D1/D2 sequence statistically different from that of Z. rouxii. The findings obtained in this work suggest that the genomic background of strains ABT301 and ABT601 is different from the other Zygosaccharomyces species. We speculated that they could belong to a new putative species related to Z. rouxii.

Zygosaccharomyces sapae sp. nov., isolated from Italian traditional balsamic vinegar

“…nov. in relevant genome-level properties. These results were also confirmed by phylogenetic divergences among these strains, previously demonstrated using the mitochondrial cytochrome oxidase II gene (COX2) and two nuclear housekeeping markers (imidazole-glycerol-phosphate dehydratase, HIS3, and Na + / H + -antiporter, ZrSOD2, respectively) (Solieri et al, 2007).…”

“…The ITS domain sequencing of strains ABT301 T and ABT601 revealed that three non-orthologous ITS sequences (arbitrarily referred to as copies 1-3) coexisted within the genome of a single strain (Solieri et al, 2007), whereas two ITS sequences were found from strain ATCC 42981 (Gordon & Wolfe, 2008). An increasing number of examples have been recently reported on intragenomic polymorphism in ITS sequences within the same strain of fungal and yeast species (Wang & Yao, 2005;Fell et al, 2007;Kageyama et al, 2007;Jacques et al, 2009;Connell et al, 2010;Saksinchai et al, 2012).…”

“…The entire internal transcribed spacer (ITS) domains (ITS 1, ITS 2 and the intervening 5.8S rRNA gene) were amplified with primers ITS1 and ITS4 (White et al, 1990) and cloned according to Solieri et al (2007). ITS PCR-restriction fragment length polymorphism (RFLP) analysis was carried out as reported by Solieri et al (2007). PCR products of D1/D2 and ITS domains were purified and sequenced as previously reported (Solieri et al, 2007), using the same primers as those for PCR, as well as the internal primer sets NL2A and NL3A (Kurtzman & Robnett, 1998) and ITS2 and ITS3 (White et al, 1990), respectively.…”

“…ITS PCR-restriction fragment length polymorphism (RFLP) analysis was carried out as reported by Solieri et al (2007). PCR products of D1/D2 and ITS domains were purified and sequenced as previously reported (Solieri et al, 2007), using the same primers as those for PCR, as well as the internal primer sets NL2A and NL3A (Kurtzman & Robnett, 1998) and ITS2 and ITS3 (White et al, 1990), respectively. Sequences were edited and assembled using SeqMan software (DNASTAR) and BLASTed against the GenBank database to retrieve sequences of the closest relatives.…”

Cultivable microorganisms associated with honeys of different geographical and botanical origin

“…Nine yeast species were identified, but only Z. rouxii and D. hansenii were directly identified by 5.8S rRNA gene RFLP; for the other species the sequencing of the D1/D2 domain of the 26S rRNA gene was necessary, because atypical restriction profiles of 5.8S-ITS were registered. An atypical polymorphism for this region is not surprising, since many authors observed this behaviour in several yeasts (Solieri et al, 2007;Tofalo et al, 2009). The two osmotolerant Z. mellis and Z. rouxii are commonly associated with the honey environment (Deak, 2007;Carvalho et al, 2006), but no previous detection of A. pullulans, C. uzbekistanensis and D. hansenii in honey sources are available in literature.…”