In mammals there are at least three isoforms of the glycolytic enzyme enolase encoded by three similar genes:a, p and y. In this report we describe the isolation and characterization of the human a-enolase locus. The gene appears to exist as a single copy in the haploid genome and is composed of 12 exons distributed over more than 18000 bases. The structure of this gene has a high degree of similarity to that of the human and rat y-enolase genes, with identical positions for all the intron regions. Primer extension and S1 nuclease protection experiments indicate that transcription is initiated at multiple sites. The putative promoter region, like that of other housekeeping genes, lacks canonical TATA and CAAT boxes, is extremely G + C-rich and contains several potential SP1 binding sites. Furthermore, various sequences similar to known regulatory elements were detected.The functional role of multiple enzyme isoforms and the regulatory mechanisms required for developmental and tissuespecific expression of these isoforms are still largely unknown. The glycolytic enzyme enolase (2-phospo-~-glycerate hydrolase) represents a suitable model for the study of these mechanisms. Three distinct isoforms of the enzyme, referred to as a or non-neuronal enolase, p or muscle-specific enolase and y or neuron-specific enolase are present in both avian and mammalian tissues [l]. The active enzyme is a homodimer of non-covalently linked subunits, each a, p and y subunit is encoded by a separate gene as previously proposed [2] and recently established by cDNA cloning in human [3-51, rat [6 -81, and mouse [9].While the y isoform is mainly detected in cells of neuronal origin and the p isoform is found in adult skeletal muscle, the a isoform is widely distributed among different tissues and is the major form of enolase present in the early stage of embryonic development. Isoform switch occurs along with terminal differentiation in neurons and skeletal muscle cells from the a-to the y-and p-enolase respectively [2, 10, 111. Although the isolated isoenzymes have been studied for many years and a substantial body of information on their biochemical, kinetic, and immunological properties [I21 as well as on the crystallographic structure [I31 has been collected, very little is known about the control of expression of the enolase genes. Beside the already mentioned differential expression during development and in various cell types, transcriptional induction of the a-enolase gene has been shown upon mitogenic stimulation of human peripheral-blood lymphocytes [3], as well as in quiescent rat fibroblast stimulated with growth factors or serum [14]. High levels of expression of the y isoform have been detected in many tumors of nonneuronal origin [5] suggesting lack of tissue-specific control in transformed cells. Furthermore, the finding that one of the two enolase isoenzymes of the budding yeast Saccharomyces cerevisiue may be involved in both thermal tolerance and growth control [15] and the identification of the lens structural prote...

The purpose of this work was to investigate the presence of C. zemplinina yeasts in Sicilian musts and grapes and to identify strains of oenological interest. We report on the taxonomical reclassification of Candida yeast isolates from Sicilian musts and on the selection of one strain of oenological interest (Cz3), based on mixed micro-fermentation experiments in sterile Nero d'Avola musts. Our results show that Candida zemplinina is abundant in Sicilian grapes and musts, and that the Cz3 strain is suitable for Candida zemplinina/Saccharomyces cerevisiae mixed fermentations. The higher glycerol content and the lower ethanol level stood out as the most promising features of the wines obtained upon sequential inoculation of the Cz3 and (S. cerevisiae) NDA21 yeast starters. We therefore have isolated a Sicilian Cz strain endowed with very promising features for the future development of mixed fermentation protocols.

Aims:  The aim of this study was to identify the non‐Saccharomyces yeast populations present in the grape must microflora from wineries from different areas around the island of Sicily. Methods and Results:  Yeasts identification was conducted on 2575 colonies isolated from six musts, characterized using Wallerstein Laboratory (WL) nutrient agar, restriction analysis of the amplified 5·8S‐internal transcribed spacer region and restriction profiles of amplified 26S rDNA. In those colonies, we identified 11 different yeast species originating from wine musts from two different geographical areas of the island of Sicily. Conclusions:  We isolated non‐Saccharomyces yeasts and described the microflora in grape musts from different areas of Sicily. Moreover, we discovered two new colony morphologies for yeasts on WL agar never previously described. Significance and Impact of the Study:  This investigation is a first step in understanding the distribution of non‐Saccharomyces yeasts in grape musts from Sicily. The contribution is important as a tool for monitoring the microflora in grape musts and for establishing a new non‐Saccharomyces yeast collection; in the future, this collection will be used for understanding the significance of these yeasts in oenology.

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Dr Daniela Barbera, for help with the triangle tests. We thank Dr Antonio Sparacio and the oenologist Salvatore Sparla for help with the Merlot and Nero d'Avola grapes. We also acknowledge the "Valle dell'Acate" winery for help with the Frappato grapes. Funds for this work were provided through an intramural grant of the IRVO

In recent years, the preservation of biodiversity has become an important issue. Despite much public discussion, however, current practices in the food industry seldom take account of its potential economic importance: on the contrary, the introduction of industrialized agriculture practices over large areas has often resulted in a dramatic reduction in biodiversity. In this paper, we report on the remarkable degree of biodiversity in the wine yeast populations naturally present in a small area of Sicily (Italy) where traditional (non-industrial) winery practices are still in place. Out of more than 900 Saccharomyces yeast isolates recovered from late spontaneous fermentations, we detected at least 209 strains. Most interestingly, when evaluated at the fermentation and technological level, a number of isolates were found to be superior to industrial yeast strains. Out of a selected group, isolates from two strains were used for experimental fermentations in a winery environment and the quality of the wines produced was assessed at the technological, quality and sensory levels. Given that the characteristics of the wines produced were found to be industrially appealing, the study demonstrated the economic potential of preserving the patrimony of Sicilian yeast biodiversity and highlighted the importance of maintaining traditional wine making practices.

High throughput sequencing allowed the discovery of many new viruses and viral organizations increasing our comprehension of virus origin and evolution. Most RNA viruses are currently characterized through similarity searches of annotated virus databases. This approach limits the possibility to detect completely new virus-encoded proteins with no detectable similarities to existing ones, i.e., ORFan proteins. A strong indication of the ORFan viral origin in a metatranscriptome is the lack of DNA corresponding to an assembled RNA sequence in the biological sample. Furthermore, sequence homology among ORFans and evidence of co-occurrence of these ORFans in specific host individuals, provides further indication of a viral origin. Here we use this theoretical framework to report the finding of three conserved clades of protein-coding RNA segments without a corresponding DNA in fungi. Protein sequence and structural alignment suggest these proteins are distantly related to viral RNA dependent RNA polymerases (RdRP). In these new putative viral RdRP clades no GDD catalytic triad is present, but the most common putative catalytic triad is NDD, and a clade with GDQ, a triad previously unreported at that site. SDD, HDD ADD are also represented. For most members of these three clades, we were able to associate a second genomic segment, coding for a protein of unknown function. We provisionally named this new group of viruses ormycovirus. Interestingly, all the members of one of these sub-clades (gammaormycovirus) accumulate more minus sense RNA than plus sense RNA during infection.

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