Espacio de Biología Vegetal del Noreste, Centro Universitario de Tacuarembó, Universidad de la República, Tacuarembó, Uruguay.
Area Enología y Biotecnología de Fermentaciones, Facultad de Química, Universidad de la República, Montevideo, Uruguay.
Appl Environ Microbiol. 2018 Dec 13;85(1). doi: 10.1128/AEM.01959-18. Print 2019 Jan 1.
is the main genus of the apiculate yeast group that represents approximately 70% of the grape-associated microflora. is emerging as a promising species for quality wine production compared to other non- species. Wines produced by with consistently exhibit more intense fruity flavors and complexity than wines produced by alone. In this work, genome sequencing, assembling, and phylogenetic analysis of two strains of showed that it is a member of the complex and it diverged before the whole-genome duplication (WGD) event from this clade. Specific flavor gene duplications and absences were identified in the genome compared to 14 fully sequenced industrial genomes. The increased formation of 2-phenylethyl acetate and phenylpropanoids such as 2-phenylethyl and benzyl alcohols might be explained by gene duplications of aromatic amino acid aminotransferases ( and ) and phenylpyruvate decarboxylases (). Transcriptome and aroma profiles under fermentation conditions confirmed these genes were highly expressed at the beginning of stationary phase coupled to the production of their related compounds. The extremely high level of acetate esters produced by compared to that by is consistent with the identification of six novel proteins with alcohol acetyltransferase (AATase) domains. The absence of the branched-chain amino acid transaminases () and acyl coenzyme A (acyl-CoA)/ethanol -acyltransferases () genes correlates with 's reduced production of branched-chain higher alcohols, fatty acids, and ethyl esters, respectively. Our study provides sustenance for understanding and potentially utilizing genes that determine fermentation aromas. The huge diversity of non- yeasts in grapes is dominated by the apiculate genus Two native strains of applied to winemaking because of their high oenological potential in aroma and fermentation performance were selected to obtain high-quality genomes. Here, we present a phylogenetic analysis and the complete transcriptome and aroma metabolome of during three fermentation steps. This species produced significantly richer flavor compound diversity than , including benzenoids, phenylpropanoids, and acetate-derived compounds. The identification of six proteins, different from ATF, with diverse acetyltransferase domains in offers a relevant source of native genetic variants for this enzymatic activity. The discovery of benzenoid synthesis capacity in provides a new eukaryotic model to dilucidate an alternative pathway to that catalyzed by plants' phenylalanine lyases.
是尖孢酵母属的主要属，代表了约 70%的葡萄相关微生物群。与其他非尖孢酵母属物种相比，该属种正在成为优质葡萄酒生产的有前途的物种。用与其他种共同发酵生产的葡萄酒比单独用种发酵生产的葡萄酒表现出更浓郁的果味和更复杂的风味。在这项工作中，对两个尖孢酵母属菌株的基因组测序、组装和系统发育分析表明，它是复杂的成员，并且在这个分支的全基因组复制（WGD）事件之前就已经分化了。与 14 个完全测序的工业尖孢酵母属基因组相比，在属种基因组中发现了特定的风味基因重复和缺失。与苯乙醇和苯丙醇等芳香族氨基酸转氨酶（和）和苯丙酮酸脱羧酶（）相比，2-苯乙醇乙酸酯和苯丙素类化合物的形成增加可能是由于基因重复所致。在发酵条件下的转录组和香气图谱证实，这些基因在静止期开始时高度表达，与相关化合物的产生有关。与种相比，种产生的乙酸酯水平极高，这与鉴定出的六种具有醇乙酰基转移酶（AATase）结构域的新型蛋白质一致。支链氨基酸转氨酶（）和酰基辅酶 A（酰基辅酶 A）/乙醇酰基转移酶（）基因的缺失与种分支链高醇、脂肪酸和乙酯的产量降低有关。我们的研究为理解和潜在利用决定发酵香气的基因提供了支持。葡萄中庞大的非酵母菌群主要由尖孢酵母属主导。选择了两种具有高酿造潜力的本土尖孢酵母属菌株用于酿酒，以获得高质量的基因组。在这里，我们展示了在三个发酵步骤中属种的系统发育分析以及完整的转录组和香气代谢组。与种相比，该种产生的风味化合物多样性更丰富，包括苯类、苯丙素类和乙酸酯衍生化合物。在属种中发现的六种与 ATF 不同、具有不同乙酰基转移酶结构域的蛋白质为这种酶活性提供了一个相关的本土遗传变异来源。在属种中发现的苯并类化合物合成能力为阐明植物苯丙氨酸裂解酶催化的替代途径提供了一个新的真核模型。
