Glycolytic Functions Are Conserved in the Genome of the Wine Yeast Hanseniaspora uvarum, and Pyruvate Kinase Limits Its Capacity for Alcoholic Fermentation

Abstract

(anamorph ) is a predominant yeast on wine grapes and other fruits and has a strong influence on wine quality, even when starter cultures are employed. In this work, we sequenced and annotated approximately 93% of the genome. Southern and synteny analyses were employed to construct a map of the seven chromosomes present in a type strain. Comparative determinations of specific enzyme activities within the fermentative pathway in and indicated that the reduced capacity of the former yeast for ethanol production is caused primarily by an ∼10-fold-lower activity of the key glycolytic enzyme pyruvate kinase. The heterologous expression of the encoding gene, (), and two genes encoding the phosphofructokinase subunits, and, in the respective deletion mutants of confirmed their functional homology. is a predominant yeast species on grapes and other fruits. It contributes significantly to the production of desired as well as unfavorable aroma compounds and thus determines the quality of the final product, especially wine. Despite this obvious importance, knowledge on its genetics is scarce. As a basis for targeted metabolic modifications, here we provide the results of a genomic sequencing approach, including the annotation of 3,010 protein-encoding genes, e.g., those encoding the entire sugar fermentation pathway, key components of stress response signaling pathways, and enzymes catalyzing the production of aroma compounds. Comparative analyses suggest that the low fermentative capacity of compared to that of can be attributed to low pyruvate kinase activity. The data reported here are expected to aid in establishing as a non- yeast in starter cultures for wine and cider fermentations.

Genome Sequencing and Comparative Analysis of Three Hanseniaspora uvarum Indigenous Wine Strains Reveal Remarkable Biotechnological Potential

“…Whole-genome sequencing revealed comparable genome size (∼9 Mb), GC content (∼31%) and number of genes (∼4000) for the three strains ( Table 3). These data also converge on the genomic features of the other H. uvarum strains analyzed in this work (Table 4) and by other authors (Langenberg et al, 2017). Hierarchical clustering of Hanseniaspora species indicates that the H. uvarum strains included in this study form a wellsupported monophyletic clade (Figure 2A), with high levels of genomic identity and a relatively compact pan-genome, where core genes account for more than 75% of the average number of genes that are annotated in any individual strain ( Figure 2C).…”

“…Among these yeasts, the genus Hanseniaspora, which can play a critical role in the modulation of the wine sensory profile by increasing its complexity and organoleptic richness, is attracting a significant interest (Fleet, 2003). So far, the knowledge on genetics and physiology of Hanseniaspora species remains limited, notwithstanding some recent significant studies open new perspectives in the field, revealing speciesspecific properties to be explored (Langenberg et al, 2017;Seixas et al, 2019). In this context, genomics analysis may enable a correlation between genetics and useful traits, which could provide a roadmap for biotechnological exploitations (Hittinger et al, 2015;Riley et al, 2016).…”

Oenological Impact of the Hanseniaspora/Kloeckera Yeast Genus on Wines—A Review

“…Notwithstanding, there are wide differences in genome size and chromosome number in karyotyping results from natural grape samples. Besides, Hanseniaspora genus belongs to the group of yeast that does not undergo whole-genome duplication, contrary to Saccharomyces [44]. These discrepancies were previously detected in the mitochondrial DNA of H. uvarum.…”

“…As informed by karyotyping approaches, H/K species could present between seven and nine chromosomes [29,30]. In a recent study based on field inversion gel electrophoresis and the whole genome sequencing of type strain H. uvarum DSM2768, seven chromosomes were detected [44]. Notwithstanding, there are wide differences in genome size and chromosome number in karyotyping results from natural grape samples.…”

“…A key enzyme associated with the glycolytic pathway is pyruvate kinase. Langenberg et al [44] recently demonstrated the correlation between pyruvate kinase activity and the enhanced fermentative ability of SC compared with H. uvarum. The authors explained this difference was due to a lowered specific activity rather than the structure of this enzyme.…”