Unveiling the yeast interaction: Insights into the role of Saccharomyces cerevisiae metabolites in regulating Torulaspora delbrueckii aroma biosynthesis during wine fermentation.

The interactions between Saccharomyces cerevisiae and non-Saccharomyces yeasts through secreted metabolites play a crucial role in shaping wine aroma profiles, yet the underlying mechanisms remain inadequately understood. This study used a cell/medium separation strategy coupled with transcriptomic and metabolomic analyses to elucidate the influence of S. cerevisiae metabolites on aroma biosynthesis in Torulaspora delbrueckii during wine fermentation.

Random Phase Approximation Correlation Energy Using Real-Space Density Functional Perturbation Theory.

We present a real-space method for computing the random phase approximation (RPA) correlation energy within Kohn-Sham density functional theory, leveraging the low-rank nature of the frequency-dependent density response operator. In particular, we employ a cubic-scaling formalism based on density functional perturbation theory that circumvents the calculation of the response function matrix, instead relying on the ability to compute its product with a vector through the solution of the associated Sternheimer linear systems. We develop a large-scale parallel implementation of this formalism using the subspace iteration method in conjunction with the spectral quadrature method while employing the Kronecker product-based method for the application of the Coulomb operator and the conjugate orthogonal conjugate gradient method for the solution of the linear systems.

Phosphoryl group wires stabilize pathological tau fibrils as revealed by multiple quantum spin counting NMR.

Hyperphosphorylation of the protein tau is one of the biomarkers of neurodegenerative diseases in the category of tauopathies. However, the molecular level, mechanistic, role of this common post-translational modification (PTM) in enhancing or reducing the aggregation propensity of tau is unclear, especially considering that combinatorial phosphorylation of multiple sites can have complex, non-additive, effects on tau protein aggregation. Since tau proteins stack in register and parallel to elongate into pathological fibrils, phosphoryl groups from adjacent tau strands with 4.

A comparative study to investigate the individual contribution of metabolic and physical interaction on volatiles formation in the mixed fermentation of Torulaspora delbrueckii and Saccharomyces cerevisiae.

It is well-known that the co-inoculation of Saccharomyces cerevisiae and non-Saccharomyces strains can modulate and improve the aromatic quality of wine through their multi-level interactions. However, the individual contribution of metabolic interaction (MI) and physical interaction (PI) on wine volatiles remains poorly understood. In this work, we utilized a double-compartment bioreactor to examine the aromatic effect of MI and PI by comparing the volatiles production in Torulaspora delbrueckii and Saccharomyces cerevisiae single fermentations to their mixed fermentations with or without physical separation.

Real-space density kernel method for Kohn-Sham density functional theory calculations at high temperature.

Kohn-Sham density functional theory calculations using conventional diagonalization based methods become increasingly expensive as temperature increases due to the need to compute increasing numbers of partially occupied states. We present a density matrix based method for Kohn-Sham calculations at high temperatures that eliminates the need for diagonalization entirely, thus reducing the cost of such calculations significantly. Specifically, we develop real-space expressions for the electron density, electronic free energy, Hellmann-Feynman forces, and Hellmann-Feynman stress tensor in terms of an orthonormal auxiliary orbital basis and its density kernel transform, the density kernel being the matrix representation of the density operator in the auxiliary basis.

Effects of three indigenous non-Saccharomyces yeasts and their pairwise combinations in co-fermentation with Saccharomyces cerevisiae on volatile compounds of Petit Manseng wines.

The combined use of selected Saccharomyces cerevisiae and non-Saccharomyces strains is becoming an effective way to achieve wine products with distinctive aromas. The purpose of this study was to further improve the wine aroma complexity through optimizing inoculation protocols of multi-starters. The three indigenous non-Saccharomyces strains (Torulaspora delbrueckii, Hanseniaspora vineae, and Lachancea thermotolerans) and their pairwise combinations (co-inoculation) were sequentially inoculated with S.

Use of Indigenous and Co-fermentation With to Improve the Aroma Diversity of Vidal Blanc Icewine.

Using novel non- strains is regarded as an effective way to improve the aroma diversity of wines to meet the expectations of consumers. The non- Hanseniaspora vineae and have good aromatic properties useful for the production of table wine. However, no detailed information is available on their performances in icewine fermentation.

Use of Co-fermentation With Two Strains With Different Aromatic Characteristic to Improve the Diversity of Red Wine Aroma Profile.

The use of selected and non- strains as mixed starters has advantages over pure fermentation due to achieving wine products with distinctive and diversified aroma expected by consumers. To obtain a way to improve the aroma diversity and increase the differentiation of wine product, in this study, the aromatic effect of multi-culture of indigenous (12), simultaneous and sequential inoculation with two strains (indigenous icewine yeast 45 and commercial yeast BDX) with different enological characteristics were investigated in laboratory-scale 20 L fermenter, respectively. The results showed that co-fermented with different strain could generate diversified physicochemical and aromatic quality of wine as evidenced by PCA.