Identification and Molecular Characterization of Novel Mycoviruses in <i>Saccharomyces</i> and Non-<i>Saccharomyces</i> Yeasts of Oenological Interest
2021
Dalila Crucitti | Marco Chiapello | Daniele Oliva | Marco Forgia | Massimo Turina | Francesco Carimi | Francesca La Bella | Davide Pacifico
Wine yeasts can be natural hosts for dsRNA, ssRNA viruses and retrotransposon elements. In this study, high-throughput RNA sequencing combined with bioinformatic analyses unveiled the virome associated to 16 <i>Saccharomyces cerevisiae</i> and 8 non-<i>Saccharomyces</i> strains of oenological interest. Results showed the presence of six viruses and two satellite dsRNAs from four different families, two of which—<i>Partitiviridae</i> and <i>Mitoviridae</i>—were not reported before in yeasts, as well as two ORFan contigs of viral origin. According to phylogenetic analysis, four new putative mycoviruses distributed in <i>Totivirus</i>, <i>Cryspovirus,</i> and <i>Mitovirus</i> genera were identified. The majority of commercial <i>S. cerevisiae</i> strains were confirmed to be the host for helper L-A type totiviruses and satellite M dsRNAs associated with the killer phenotype, both in single and mixed infections with L-BC totiviruses, and two viral sequences belonging to a new cryspovirus putative species discovered here for the first time. Moreover, single infection by a narnavirus 20S-related sequence was also found in one <i>S. cerevisiae</i> strain. Considering the non-<i>Saccharomyces</i> yeasts, <i>Starmerella bacillaris</i> hosted four RNAs of viral origin—two clustering in <i>Totivirus</i> and <i>Mitovirus</i> genera, and two ORFans with putative satellite behavior. This study confirmed the infection of wine yeasts by viruses associated with useful technological characteristics and demonstrated the presence of complex mixed infections with unpredictable biological effects.
显示更多 [+] 显示较少 [-]