Wine is a processed beverage that offers high nutritional and health benefits. It is produced from grape must, which undergoes fermentation by yeasts (and sometimes lactic acid bacteria) to create a product that is highly appreciated by consumers worldwide. However, if only one type of yeast, specifically Saccharomyces cerevisiae, were used in the fermentation process, the resulting wine would lack aroma and flavor and may be rejected by consumers. To produce wine with a desirable taste and aroma, non-Saccharomyces yeasts are necessary. These yeasts contribute volatile aromatic compounds that significantly impact the wine’s final taste. They promote the release of primary aromatic compounds through a sequential hydrolysis mechanism involving several glycosidases unique to these yeasts. This review will discuss the unique characteristics of these yeasts (Schizosaccharomyces pombe, Pichia kluyveri, Torulaspora delbrueckii, Wickerhamomyces anomalus, Metschnikowia pulcherrima, Hanseniaspora vineae, Lachancea thermotolerans, Candida stellata, and others) and their impact on wine fermentations and co-fermentations. Their existence and the metabolites they produce enhance the complexity of wine flavor, resulting in a more enjoyable drinking experience.

Consumer demands for new sensory experiences have driven the research of unconventional yeasts in beer. While much research exists on the use of various common Saccharomyces cerevisiae strains as well as non-Saccharomyces yeasts, there exists a gap in knowledge regarding other non-cerevisiae Saccharomyces species in the fermentation of beer, outside that of S. pastorianus. Here, five distinct species of Saccharomyces from the UC Davis Phaff Yeast Culture Collection, as well as one interspecies hybrid from Fermentis, were chosen to ferment 40 L pilot scale beers. S. kudriavzevii, S. mikatae, S. paradoxus, S. bayanus, and S. uvarum yeasts were fermented in duplicate, with one fermenter in each pair receiving 10 g/L dry-hop during fermentation. Analytical measurements were made each day of fermentation and compared to controls of SafAle US-05 and SafLager W 34/70 for commercial brewing parameters of interest. Finished beers were also analyzed for aroma, taste, and mouthfeel to determine the flavor of each yeast as it pertains to brewing potential. All beers exhibited spicy characteristics, likely from the presence of phenols; dry-hopping increased fruit notes while also increasing perceived bitterness and astringency. All of the species in this study displayed great brewing potential, and might be an ideal addition to beer depending on a brewery’s desire to experiment with flavor and willingness to bring a new yeast into their production environment

Beer is a fermented beverage with a history as old as human civilization and its productive process has been spread all around the world becoming unique in every country and iconic of entire populations. Ales and lagers are by far the most common beers; however, the combination of raw materials, manufacture techniques and aroma profiles are almost infinite, so it is not surprising to notice that there is a large amount of different beer styles, each of them with unique characteristics. Nowadays, diversification is becoming increasingly important in the brewing market and the brewers are continuously interested in improving and extending the already wide range of products, especially in craft brewery. One of the major components that can have a deep impact on the final product is yeast, since it is able to convert carbohydrates in wort, especially maltose and maltotriose, into ethanol, carbon dioxide and other minor aroma-active compounds. Saccharomyces cerevisiae (top‐fermenting yeasts used to produce ales) and Saccharomyces pastorianus (cryotolerant bottom‐fermenting hybrids between S. cerevisiae and Saccharomyces eubayanus responsible for the fermentation of lagers) are most used in breweries. However, an increasing number of different yeast starter cultures are commercially available, to improve the production efficiency also at relative low temperatures and to obtain desirable and diversified aroma profiles avoiding undesired compounds. Four main genetic engineering-free trends are becoming popular in craft brewing yeast development: 1) the research for novel reservoirs as source of new performant S. cerevisiae yeasts; 2) the creation of synthetic hybrids between S. cerevisiae and Saccharomyces non-cerevisiae in order to mimic lager yeasts by expanding their genetic background; 3) the exploitation of evolutionary engineering approaches; 4) the usage of non-Saccharomyces yeasts either in co-coculture or in sequential fermentation with S. cerevisiae. In the present work we summarized pro and contra of these approaches and provided an overview on the most recent advances on how brewing yeast genome evolved and domestication took place. Finally, we delineated how the correlations maps between genotypes and relevant brewing phenotypes can assist and further improve the search for novel craft beer starter yeasts.

Fermented food matrices, including beverages, can be defined as the result of the activity of complex microbial ecosystems where different microorganisms interact according to different biotic and abiotic factors. Certainly, in industrial production the technological processes aim to control the fermentation to place safe foods on the market. Therefore, if food safety is the essential prerogative, consumers are increasingly oriented towards a healthy and conscious diet driving the production and consequently the applied research towards natural processes. In this regard, the aim to guarantee safety, quality and diversify of products should be reached limiting or avoiding the addition of antimicrobials or synthetic additives using the biological approach. In this paper, following the recent re-evaluation of non-Saccharomyces yeasts (NSYs) has been re-viewed the bio-protectant and biocontrol activity with a particular focus on their antimicrobial power, probiotic features and promoting functional aspects. In this review, the authors would underline the contribution of NSYs in all food production chain and its role in the technological and fermentative features for their practical and useful use as biocontrol agent in food preparations.

Non-alcoholic beer (NAB) or low alcoholic beer (LAB) are taking over the market with a growing sale. Sus-tainable recycling and valorization of exhausted brewer’s spent grains (BSG) coming from craft beer is a relevant issue in brewing process. In this work, recycled BSG and BSG+GJ (supplemented with 10% grape juice) were used as wort-substrate to inoculate already selected non-conventional yeasts to produce NABLAB craft beer. Results showed that wort composed by only recycled BSG produced appreciate NAB beers (ethanol from 0.12% to 0.54 % v/v) while the addition of 10% of grape juice made LAB beers (ethanol from 0.82 to 1.66 % v/v). As expected, volatile compounds production was highest with the addition of grape juice. Lachancea thermotolerans confirmed the lactic acid production and, as Saccharomyces cerevisiae, is characterized by (in both worts) ethyl butyrate and isoamyl acetate, while Torulaspora delbrueckii produced relevant amounts of exanol, phenylethyl acetate and β-phenyl ethanol (wort added with grape juice). Wickeramhomyces anomalus and Pichia kluyvery showed consistent volatile production but only in wort with grape juice addition where a fermentation activity was exhibited. The overall results indicated that reused BSGs, non-conventional yeasts and grape juice is a suitable strategy for specialty NABLAB beer.

Despite well-documented health benefits of probiotics Saccharomyces, its application in oral health has not been comprehensively assessed. Dental caries is a transmissible disease initiated by acid production of cariogenic bacteria and yeast, such as Streptococcus mutans and Candida albicans, on tooth enamel and followed by subsequent enamel demineralization. Here, we investigated the effect of two Saccharomyces strains (Saccharomyces boulardii, Saccharomyces cerevisiae) on S. mutans-C. albicans cross-kingdom interactions using a cariogenic planktonic model. Viable cells, pH changes and gene expression were measured. S. cerevisiae and S. boulardii inhibited the growth of C. albicans either in dual-, or multi-species conditions. Saccharomyces also inhibited C. albicans hyphal formation. Furthermore, Saccharomyces reduced the acidity of the culture medium which usually plummeted below pH 5 when S. mutans and C. albicans were present in the model. The presence of Saccharomyces maintained the culture medium above 6 even after overnight incubation, demonstrating a protective potential against dental enamel demineralization. S. boulardii significantly downregulated S. mutans atpD and eno genes expression. Overall, our results shed light on a new promising candidate, Saccharomyces, for dental caries prevention due to its potential to create a less cariogenic environment marked by a neutral pH and reduced growth of C. albicans.

Background: Aflatoxins (AFs) as toxic compounds are widely spread. They are frequent contaminants of crops that are produced by fungi species. Corn is of crops that widely used in the corn dry milling process; a four-step procedure comprises grain handling and milling, liquefaction and saccharification, fermentation, and co-product recovery that produces ethanol and animal feed. However, it is possible that corn as a feed for dry milling process might be contaminated with AFs. Therefore, monitoring AFs in during widespread this process results having a better understanding of the fate of AFs. Methods: In this study, a sample of corn kernel was contaminated with a high level of AFs using Aspergillus parasiticus. Then, the corn flour comprising 23400.5 µg/kg of the total level of aflatoxins (AFT), was hydrolyzed by enzymes and acid for ethanol fermentation with Saccharomyces cerevisiae. Also, the level of AFs was monitored during ethanol fermentation process. Results: The results showed that AFs did not detect in the ethanol produced through fermentation and it was safe. Also, during the experiments, the AFT level reduced by 58.5 and 95.7% for the ethanol fermentation with simultaneous saccharification and fermentation and ethanol production with acidic hydrolysis, respectively. Conclusion: The results of this study showed that highly contaminated corn with AFs can be used for ethanol fermentation through dry milling process and the produced ethanol was safe.

The increasing demand for craft beer drives the search for novel ale yeast cultures from brew-ing-related wild environments. The focus of bioprospecting for craft cultures is to identify feral yeasts suitable to imprint unique sensorial attributes to the final product. Here, we integrated phylogenetic, genotypic, genetic, and metabolomic techniques to demonstrate that sour beer during aging in wooden barrel is a source of suitable craft ale yeast candidates. Differently from traditional lambic beer maturation phase, during aging of sour-matured production style beer, different biotypes of Saccharomyces cerevisiae dominated the cultivable in-house mycobiota, fol-lowed by Pichia membranifaciens, Brettanomyces bruxellensis, and Brettanomyces anomalus. In addi-tion, three putative S. cerevisiae x Saccharomyces uvarum hybrids were identified. S. cerevisiae feral strains sporulated, produced viable monosporic progenies, and have STA1 gene as well as the full-length promoter. During hopped wort fermentation four S. cerevisiae strains and the S. cere-visiae x S. uvarum hybrid WY213 overcame non-Saccharomyces strains in fermentative rate and ethanol production, except for P. membranifaciens WY122. This strain consumed maltose after a long lag phase, in contrast with the phenotypic profile descripted for the species. According to STA1+ genotype S. cerevisiae partially consumed dextrin, but no 4-vynil guaiacol was detected among VOCs, suggesting that these strains were phenolic off flavor-negative (POF-). In conclu-sion, the strains characterized here have relevant brewing properties and are exploitable as in-digenous craft beer starters.

The aim of the present trial was to evaluate the growth performance of buffalo calves fed diets characterized by different forage/concentrate ratio with or without the Saccharomyces Cerevisiae supplementation (CBS 493.94, Yea-Sacc®). Twenty-four male buffalo calves (mean age 145.1 ± 16.1 days; mean weight 108.0 ± 18.7) were assigned randomly to 4 groups, homogeneous for age, fed four different diets: diet 1 F:C ratio 50:50; diet 2 F:C ratio 30:70; diet 3 F:C ratio 50:50 + Yea-Sacc® and diet 4 F:C ratio 30:70 + Yea-Sacc®. Buffalo calves were individually weighted before the start of the experiment and the data were used as a covariate, monthly until the end of the trial. Dry matter intake (DMI), daily weight gain (DWG) and feed conversion ratio (FCR) were calculated. The differences in diets’ composition significantly (p

Saccharomyces cerevisiae (S. cerevisiae) ethanol fermentation has left an indelible trace in human history. It is regarded as the original beverage synthesis, and has developed into an essential energy supply for mankind today. However, the history of ethanol synthesis using S. cerevisiae, including the mechanism analysis process, has not been carefully and succinctly reported. In this paper, we review the history of ethanol synthesis using S. cerevisiae. In addition, we also review the substrates that drive S. cerevisiae ethanol synthesis, including the utilization of glucose, sucrose, starch and molasses, in order to summarize the current development status and to contribute to the further improvement of this field.

Yeast extract is widely used in different food industries as a flavoring agent or vitamin supplement. In this study, a process was optimized for the production of yeast extract from Baker’s yeast (Saccharomyces cerevisiae). A glass vessel stirred fermenter was used for the cultivation of yeast biomass. The effect of various physical and chemical factors was evaluated on the production of yeast cells and optimum conditions for the production of maximum yeast biomass were determined. The optimum growth was obtained at 30ºC with pH 4.5 using molasses as a substrate supplemented with urea at 150rpm. Yeast cells were then separated by centrifugation and ruptured and autolysis was observed to be the most feasible method. Among various method employed to dry the yeast extract, spray dryer appeared as most efficient one. Yeast extract obtained after drying was subjected to different analyses and compared with commercial yeast extract. The produced yeast extract was applied in media preparation to grow different microorganisms including yeast, bacteria and fungi and considerable growth was observed. These results indicated that the developed process is a cost effective alternate approach for the production of yeast extract.

Chondroitin is a glycosaminoglycan that has gained widespread use in nutraceuticals and pharmaceuticals, mainly for treating osteoarthritis. Traditionally, it has been extracted from animal cartilage but recently, biotechnological processes have emerged as a commercial alternative to avoid the risk of viral or prion contamination and offer a vegan-friendly source. Typically, these methods involve producing the chondroitin backbone using pathogenic bacteria and then modifying it enzymatically through the action of sulfotransferases. Despite the challenges of expressing active sulfotransferases in bacteria, the use of eukaryotic microorganisms is still limited to a few works using Pichia pastoris. To create a safer and efficient biotechnological platform, we have constructed a biosynthetic pathway for chondroitin production in S. cerevisiae as a proof-of-concept. Up to 125 mg/L and 200 mg/L of intracellular and extracellular chondroitin were produced, respectively. Furthermore, as genome-scale models are valuable tools for identifying novel targets for metabolic engineering, a stoichiometric model of chondroitin-producing S. cerevisiae has been developed and used in optimization algorithms. Our research has yielded several novel targets, such as uridine diphosphate(UDP)-N-acetylglucosamine pyrophosphorylase (QRI1), glucosamine-6-phosphate acetyltransferase (GNA1) or N-acetylglucosamine-phosphate mutase (PCM1) overexpression that might enhance chondroitin production, which will guide future experimental research to develop more efficient host organisms for the biotechnological production process.

In Brazil, sucrose-rich broths (cane juice and/or molasses) are used to produce billions of liters of both fuel ethanol and cachaça per year using selected Saccharomyces cerevisiae industrial strains. Aiming to improve this disaccharide fermentation, we have first determined the genetic characteristics, by array comparative genomic hybridization, of a group of 8 fuel ethanol and 5 cachaça industrial yeasts that tend to dominate the fermentors during the production season. The widespread presence of SUC genes encoding invertase at multiple telomeres has been shown to be a common feature of both baker’s and distillers’ yeast strains and is postulated to be an adaptation to sucrose-rich broths. Our results show that only two strains (one fuel ethanol and one cachaça yeast) have amplification of the SUC genes, with high invertase activity. The other industrial yeast strains had a single SUC locus (SUC2) in their genome, with different patterns of invertase activity. These results indicate that invertase activity probably does not limit sucrose fermentation during fuel ethanol and cachaça production by these industrial strains. Using this knowledge, we changed the mode of sucrose metabolism of an industrial strain by avoiding extracellular invertase activity, overexpressing the intracellular invertase, and increasing its transport through the AGT1 permease. This approach allowed higher ethanol production from sucrose by the modified industrial yeast when compared to its parental strain.

The unicellular eukaryote S. cerevisiae is an invaluable resource for the study of basic eukaryotic cellular and molecular processes. However, due to its small size compared to other eukaryotic organisms the study of subcellular structures is challenging. Expansion microscopy (ExM) holds great potential to study the intracellular architecture of yeast, especially when paired with pan-labelling techniques visualising the full protein content inside cells. ExM allows to increase imaging resolution by physically enlarging a fixed sample that is embedded and cross- linked to a swellable gel followed by isotropic expansion in water. The cell wall present in fungi – including yeast – and Gram-positive bacteria is a resilient structure that resists denaturation and conventional digestion processes usually used in ExM protocols, resulting in uneven expansion. Thus, the digestion of the cell wall while maintaining the structure of the resulting protoplasts are crucial steps to ensure isotropic expansion. For this reason, specific experimental strategies are needed, and only a few protocols are currently available. We have developed a modified ExM protocol for S. cerevisiae, with 4x expansion factor, which allows the visualisation of the ultrastructure of the cells. Here, we describe the experimental procedure in detail, focusing on the most critical steps required to achieve isotropic expansion for ExM of S. cerevisiae.

Many contaminant yeast strains able to survive inside fuel ethanol industrial vats show detrimental cell surface phenotypes, such as filamentation, invasive growth, flocculation, biofilm formation and excessive foam production. Previous studies have linked some of these phenotypes to the expression of FLO genes, and the presence of gene length polymorphisms causing the expansion of FLO gene size appears to result in stronger flocculation and biofilm formation phenotypes. We have performed here a molecular analysis of FLO1 and FLO11 gene polymorphisms present in contaminant strains of S. cerevisae from Brazilian fuel ethanol distilleries showing strong foaming phenotypes during fermentation. The size variability of these genes was correlated with cellular hydrophobicity, flocculation and highly foaming phenotypes in these yeast strains. Our results also show that deleting the major activator of FLO genes (the FLO8 gene) from the genome of a contaminant and highly foaming industrial strain avoids problematic foam formation, flocculation, invasive growth and biofilm production by the engineered (flo8∆::BleR / flo8Δ::kanMX) yeast strain. Thus, the characterization of highly foaming yeasts and the influence of FLO8 in this phenotype opens new perspectives for yeast strain engineering and optimization in the sugarcane fuel-ethanol industry.

Genome-scale engineering and custom synthetic genomes are reshaping the next generation of industrial yeast strains. The Cre-recombinase mediated chromosomal rearrangement mechanism of designer synthetic Saccharomyces cerevisiae chromosomes, known as SCRaMbLE, is a powerful tool which allows rapid genome evolution upon command. This system is able to generate millions of novel genomes with potential valuable phenotypes, but the excessive loss of essential genes often results in poor growth or even the death of cells with useful phenotypes. In this study we expanded the versatility of SCRaMbLE to industrial strains, and evaluated different control measures to optimise genomic rearrangement, whilst limiting cell death. To achieve this, we have developed RED (Rapid Evolution Detection), a simple colorimetric plate-assay procedure to rapidly quantify the degree of genomic rearrangements within a post-SCRaMbLE yeast population. RED-enabled semi-synthetic strains were mated with haploid progeny of industrial yeast strains to produce stress tolerant heterozygous diploid strains. Analysis of these heterozygous strains with the RED-assay, genome sequencing and custom bioinformatics scripts demonstrated a correlation between RED-assay frequencies and physical genomic rearrangements. Here we show that RED is a fast and effective method to evaluate optimal SCRaMbLE induction times of different Cre-recombinse expression systems for the development of industrial strains.

Concern for global health security and the environment due to the emergence of antibiotic-resistant bacteria and antibiotic residues in meat and other livestock products has led many countries to restrict the use of antibiotics in animal feed. This experiment was performed to assess the impact of dietary supplementation with a probiotic (Bacillus subtilis) and a postbiotic (Saccharomyces cerevisiae fermentation product) on growth performance, carcass traits, blood haemato-biochemical profile, gut microbiome, gut morphology, and immune response in broilers as an alternative to antimicrobials in poultry production system to minimize the effect on global health security. A total of 324-day-old Ven Cobb 400 broiler chicks were randomly divided into three dietary groups, each containing 12 replicated pens (n = 12), .and each replicate contained nine broiler chickens. The dietary groups consisted of 1) a basal diet without any growth promoting (T1), 2) the basal diet augmented with Bacillus subtilis at 200 g/MT feed (T2), and 3) the basal diet supplemented with Saccharomyces cerevisiae fermentation product at 1.25 kg/MT feed (T3). To calculate body weight gain, all birds and residual feed were weighed on a replicated basis over days 0, 7, 14, 21, 28, 35, and 42; mortality was recorded daily. Each replicate's mortality percentage was calculated and used to adjust BW, ADFI, and FCR calculations at the trial's end. At the end of the trial (42 d), two chickens from each replicate (24 chickens per group) were slaughtered for carcass traits, gut microbiome, and morphology measurements. Blood samples were collected for the haemato-biochemical profile on 35d and antibody titer on 28d and 35d.Feeding with SCFP (T3 group) significantly improved average daily feed intake (ADFI) and average daily gain (ADG) of chickens compared to the T1 (control) and T2 (probiotic) groups from 1 to 14 days of age. FCR was significantly improved (P<0.05) in SCFP-fed birds (T3) relative to the control (T1)over the entire experimental period (1-42 days). Carcass traits and blood haemato-biochemical parameters remained unaffected (P>0.05) by any diets. However, cholesterol levels and concentrations of corticosterone were significantly lower (P<0.05) in SCFP-fed birds (T3) compared to those of the probiotic (T2) and control (T1) groups. Total E. coli, Enterohaemorrhagic E. coli, ESBL-producing Enterobacteriaceae, and Salmonella counts were significantly higher in the T1group compared to T3 and T2 groups (P<0.05) and Salmonella counts were lower in T3 when compared to T2 (P<0.05). However, there was no significant difference in Lactobacillus count among treatment groups. PCR based characterization of ESBL- producing Enterobacteriaceae revealed maximum presence of blaCTX-M-Type (6/15, 40%), followed by blaSHV-Type (5/15, 33.3%) and blaTEM-Type (4/15, 26.6%). No variation in the occurrence pattern of ESBL/beta-lactamase associated genes in the studied ESBL- producing Enterobacteriaceae isolates was observed between the treatment groups. A significant increase in villi height and villi height to crypt depth ratio (VH: CD) (P<0.05) was observed in both T3 and T2 groups. Contrarily, villi widths did not vary across the dietary groups (P>0.05). The control group (T1) displayed a notable deeper in crypts when compared to the T3 and T2 groups (P<0.05). On day 28, the SCFP-fed birds (T3) and those fed the probiotics (T2) exhibited a significant increase (P<0.05) in antibody titers against Newcastle disease virus and Infectious bursal disease virus. Increase in antibody titre against IBDV in birds with the addition of SCFP in the diet was detected for the first time. However, there were no significant differences observed on day 35. The phagocytic activity of neutrophils and lymphocytes in broiler chickens did not show any noticeable variations among the different groups at day 35(P>0.05).It can be concluded that Saccharomyces cerevisiae fermentation product and Bacillus subtilis probiotic could be viable alternatives to antimicrobials in poultry production considering beneficial impacts in broilers fed antibiotic-free diet.

Saccharomyces cerevisiae fermentation products (SCFP) can potentially promote gastrointestinal growth and immunity in young livestock. However, reports within the existing literature on the effects of SCFP supplements on calves have been inconsistent; therefore, we perform the following experiments to resolve the inconsistencies. A total of 22 Holstein calves [10 d after birth, BW = 48.93 ± 3.99 kg (mean ± SD)] were assigned randomly into two groups, namely the control group (CON) and SCFP group, each having 11 replicas. The calves in the CON were fed a basal diet, while the SCFP group was fed the basal diet supplemented with 5g/head/d SCFP (NutriTek, Diamond V, Cedar Rapids, IA52404, United States) incorporated into feed. All the calves were regularly fed thrice daily at 08:00, 14:30, and 21:00 and had free access to water. A 5-day adaptation phase was followed by a 45-day experimental period. The results showed that compared to the CON, at the end of the d-45 trial, the body weight was significantly greater in the SCFP group (p < 0.05), and during the 1-45 days, the ADG was higher (p < 0.05). The FCR in the 30-45 days SCFP group was higher (p < 0.05). Furthermore, the apparent digestibility of DM, CP, EE, ADF, Ca, and P were significantly increased in the SCFP group, except for NDF (p < 0.05). The concentration of GH and IGF-1 in serum showed a tremendous increase (p < 0.05) with SCFP supplementation on d 15 and d 45. On d 15, SCFP supplementation significantly increased the serum IgA contents (p < 0.05). Notably, on d 15 and d 45, the serum concentrations of IL-1β, IL-6, and TNF-α reduced (p < 0.001). Moreover, the Actinobacteriota in the SCFP group were significantly lower than those in the CON group (p = 0.034). SCFP significantly increased the abundance of Butyricimonas, Parabacteroides, and Ruminococcus. The differences among sob, Chao1, and PD-tree groups were statistically significant (p < 0.05). In conclusion, these results demonstrate that SCFP supplementation improved ADG, apparent digestibility and serum hormone, enhanced immunity, and regulated gut microbiota, thereby jointly promoting the growth of pre-weaning calves.

The yeast Saccharomyces cerevisiae is widely used in food and nonfood industries. During industrial fermentations yeast are exposed to fluctuations in oxygen concentration, osmotic pressure, pH, ethanol concentration, nutrient availability and temperature. Fermentation performance depends on the ability of different yeast strains to adapt to these changes. Suboptimal growth conditions trigger responses to these external stimuli to allow cellular homeostasis to be maintained. Stress-specific signaling pathways are activated to coordinate changes in tran-scription, translation, protein function, and metabolic fluxes while a transient arrest of growth and cell cycle progression occur. cAMP-PKA, HOG-MAPK and CWI signalling pathways are signal transduction pathways turned on during stress re-sponse. Comprehension of the mechanisms involved in the responses and in the adaptation to these stresses during fermentation is key to improving this industrial process. The scope of this review is to outline the advancement of knowledge about the cAMP-PKA signalling and the crosstalk of this pathway with the CWI and HOG-MAPK cascades in response to the environmental challenges heat and hy-perosmotic stress.

This study aimed to evaluate the capacity of Saccharomyces cerevisiae for Cadmium absorption in Milk. Nowadays one of the most serious problems is heavy metals pollution. Applying microorgaisms as a novel biotechnology is so useful especially in foodstuffs. Among the biosorbents for heavy metals’ removal, Saccharomyces cerevisiae has got an increasing attention due to its popularity in food industry. In this regard, the effects of some important factors such as the initial metal concentration, biomass concentration and contact time on the biosorption capacity of Saccharomyces cerevisiae were studied. The biosorption was analyzed by the inductively coupled plasma mass spectrometer (ICP-MS). The maximum Cd bioremoval (70%) was at 80 μg/L of this metal concentration in milk samples containing 30×10⁸ CFU Saccharomyces cerevisiae at the end of storage time (the 4^th day). There were no significant differences in sensory and physicochemical properties of milk samples during storage (p < 0.05). The isotherm studies followed by two popular models; Langmuir and Freundlich and the results showed a better fit to the Langmuir isotherm. All together, the results of this project demonstrated that the approach of using this valuable yeast, could be applied for food and drinks’ detoxification and producing healthier foods.

In this study is developed an aerobic and anaerobic stoichiometric model for Saccharomyces cerevisiae, compartmentalized in mitochondria and cytosol. This model considers the central metabolism of S. cerevisiae and it possesses the peculiarity of having catabolic and anabolic biochemical reactions for the synthesis of the higher alcohols contained in tequila; involving 94 metabolites and 117 reactions; of which 93 correspond to biochemical internal reactions and 24 to transport fluxes between the medium and the cell. The model is validated under aerobic and anaerobic conditions for the main fermentation metabolites and it coincides with experimental results and those in silico reported in the literature. This model is used to obtain three different physiological states of S. cerevisiae through of estimation of its distributions of fluxes calculated from experimental data reported in literature of fermentation in continuous culture during the tequila production under different dilution rate (0.04-0.12 h^-1). The model developed constitutes a tool for the estimation of flux distribution maps during fermentation processes for the production of tequila, which could permit estimate yields and visualize different fermentation scenarios.

Abstract: Yeast – especially Saccharomyces cerevisiae – have long been a preferred workhorse for the production of numerous recombinant proteins and other metabolites. S. cerevisiae is a noteworthy aroma compound producer, and has also been exploited to produce foreign bioflavour compounds. In the past few years, important strides have been made in unlocking the key elements in the biochemical pathways involved in the production of many aroma compounds. The expression of these biochemical pathways in yeast often involves the manipulation of the host strain to direct the flux towards certain precursors needed for the production of the given aroma compound. This review highlights recent advances in the bioengineering of yeast – including S. cerevisiae – to produce aroma compounds and bioflavours. To capitalise on recent advances in synthetic yeast genomics, this review presents yeast as a significant producer of bioflavours in a fresh context and proposes new directions for combining engineering and biology principles to improve the yield of targeted aroma compounds.

The aim of this study was to isolate and characterize autochthonous Saccharomyces cerevisiae yeasts from Cabernet Sauvignon grape must and to analyze how they impacted the final characteristics of the wines obtained from the same must type. This work was carried out in a “Pago” winery located in Requena, Spain. Twenty-two isolates were obtained from grape must. After molecular identification and typing, 11 different strains were determined. Growth-related parameters and metabolic characteristics (glucose and fructose consumption, and ethanol, glycerol and acetic acid production) were determined by laboratory-scale fermentations (50 mL) of Cabernet Sauvignon must. From 2 L fermentation batches, residual sugar, density, ethanol concentration, titratable and volatile acidities, pH, and polyphenolic and volatile compounds were determined, as well as the sensory attributes of the produced wines. Differences between strains in the growth and metabolic parameters were observed. Eleven S. cerevisiae strain profiles were characterized to establish which strain or strains of the selected yeasts would produce the highest polyphenolic and aromatic concentration of the red Cabernet wines made in the “Pago winery” to then multiply them for their use to make the red wines of this winery.

Here we propose the concept of an electro–microbial route to uncouple food production from photosynthesis, thereby enabling production of nutritious food in space without the need to grow plant-based crops. In the proposed process, carbon dioxide is fixed into ethanol using either chemical catalysis or microbial carbon fixation, and the ethanol created is used as a carbon source for yeast to synthesize food for human or animal consumption. The process depends upon technologies that can utilize electrical energy to fix carbon into ethanol and uses an optimized strain of the yeast Saccharomyces cerevisiae to produce high quality, food grade single cell protein using only ethanol, urea, phosphate, and inorganic salts as inputs. Unlike crops using photosynthesis that require months to mature and are challenging to grow under the conditions found in space, the electro–microbial process could generate significant quantities of food on demand with potentially high yields and productivities. In this paper we explore the potential of the proposed process to provide food on demand in space, but it should be noted that this novel approach to food production has many valuable terrestrial applications too. For example, enabling food production in climatically challenged environments including turning deserts into food bowls, or utilizing surplus electricity generated from large-scale renewable power sources.

From grape cultivation to ripening and harvest timing to processing, each step can be a critical point when it comes to wine quality and phenolic composition. In this study, the influence of winemaking technology on resveratrol and quercetin content, as well as other polyphenolic compounds, was investigated. Resveratrol is a non-flavonoid polyphenolic stilbene synthesized by grape skin when damaged by infectious diseases or ionizing radiation. Quercetin is a phenol found in grape skins and stems and is produced to protect grapes from UV light damage. Trans-resveratrol and quercetin are known to act as antioxidants, reduce the risk of atherosclerosis and type 2 diabetes, inhibit the growth of cancer cells, and prevent the release of allergic and inflammatory molecules. However, the question was whether red wine could be enriched with these phenols using an innovative winemaking technology. The innovative idea was to completely replace the cold maceration process with maceration with the addition of wild yeast (Torulaspora delbrueckii, Td). Maceration with the addition of wild yeast (Td) offers the following advantages over traditional cold maceration: (1) higher concentrations of trans-resveratrol (>35-40%) and quercetin (>35-40%) in the final wine, (2) the new wine has a higher potential for human health, (3) the wine has a better aroma and stability due to the higher mannoprotein content, and (4) the better energy efficiency in the production process. The study of stability during storage and aging also included derivatives of benzoic acid and hydroxycinnamic acid, piceid, catechin, naringenin, rutin, kaempherol, hesperetin, and anthocyanins. The study found that younger wines had higher phenolic content, while storage of the wine resulted in a decrease in total phenolic content, especially monomeric stilbenes and quercetin.

In proteomics, it is essential to quantify proteins in absolute terms if we wish compare results among studies and integrate high-throughput biological data into genome-scale metabolic models. While labeling target peptides with stable isotopes allows protein abundance to be accurately quantified, the utility of this technique is constrained by the low number of quantifiable proteins that it yields. Recently, label-free shotgun proteomics has become the “gold standard” for carrying out global assessments of biological samples containing thousands of proteins. However, this tool must be further improved if we wish to accurately quantify absolute levels of proteins. Here, we used different label-free quantification techniques to estimate absolute protein abundance in the model yeast Saccharomyces cerevisiae. More specifically, we evaluated the performance of seven different quantification methods, based either on spectral counting (SC) or extracted-ion chromatogram (XIC), which were applied to samples from five different proteome backgrounds. We also compared the accuracy and reproducibility of two strategies for transforming relative abundance into absolute abundance: a UPS2-based strategy and the total protein approach (TPA). This study mentions technical challenges related to UPS2 use and proposes ways of addressing them, including utilizing a smaller, more highly optimized amount of UPS2. Overall, three SC-based methods (PAI, SAF, and NSAF) yielded the best results because they struck a good balance between experimental performance and protein quantification.

A bottom-up route towards predicting evolution relies on deep understanding of the complex network proteins form inside cells. In a rapidly expanding panorama of experimental possibilities, the most difficult question is how to conceptually approach the disentangling of such complex networks. These can exhibit varying degrees of hierarchy and modularity, which obfuscate certain protein functions that may prove pivotal for adaptation. Using the well-established polarity network in budding yeast as a case study, we first organize current literature to highlight protein entrenchments inside polarity. Following three examples, we see how alternating between experimental novelties and subsequent emerging design strategies can construct a layered understanding, potent enough to reveal evolutionary targets. We show that if you want to understand a cell’s evolutionary capacity, such as possible future evolutionary paths, seemingly unimportant proteins need to be mapped and studied. Finally, we generalize this research structure to be applicable to other systems of interest.

The [PSI⁺] nonsense-suppressor determinant of Saccharomyces cerevisiae is related to formation of heritable amyloids of the Sup35 (eRF3) translation termination factor. [PSI⁺] amyloids have variants in amyloid structure and in the strength of suppressor phenotype. Appearance of [PSI⁺], its propagation and manifestation depend primarily on chaperones. Besides chaperones, the Upf1/2/3, Siw14 and Arg82 proteins restrict [PSI⁺] formation, while Sla2 can prevent the [PSI⁺] toxicity. Here, we identify two more non-chaperone proteins involved in [PSI⁺] detoxification. We show that simultaneous lack of the Pub1 and Upf1 proteins causes lethality of [PSI⁺] cells with a strong, but not with weak suppressor phenotype. This lethality results from excessive depletion of the Sup45 (eRF1) termination factor due to its sequestration into Sup35 polymers. We also show that Pub1 acts to restrict excessive Sup35 prion polymerization, while Upf1 interferes with Sup45 binding to Sup35 polymers. These data allow considering the Pub1 and Upf1 proteins as a novel [PSI⁺] detoxification system.

Abstract: CRISPR/Cas systems are used for genome editing, both in basic science and in bio-technology. At the same time, CRISPR/Cas editors have several limitations, including insufficient specificity leading to "off-targets" and the dependence of activity on chromatin state. A number of highly specific Cas9 variants have been obtained now, but most of them are characterized by reduced activity on eukaryotic chromatin. We identified a spatial cluster of amino acid residues in the PAM-recognizing domain of Streptococcus pyogenes Cas9, whose mutations restore the activity of one of the highly specific forms of SpyCas9 without reducing its activity in Saccharomyces cere-visiae. In addition, one of these new mutations also increases the efficiency of SpyCas9-mediated editing of a site localized on the stable nucleosome. The improved Cas9 variants we obtained, which are capable of editing hard-to-reach regions of the yeast genome, may help in both basic research and yeast biotechnological applications.

Conjugation is a bacterial mechanism for DNA transfer from a donor cell to a wide range of recipients, including both prokaryotic and eukaryotic cells. In contrast to conventional DNA delivery techniques, such as electroporation and chemical transformation, conjugation eliminates the need for DNA extraction, thereby preventing DNA damage during isolation. While most established conjugation protocols allow for DNA transfer in liquid media or on a solid surface, we developed a procedure for conjugation within solid media. Such a protocol may expand conjugation as a tool for DNA transfer to species that require semi-solid or solid media for growth. Conjugation within solid media could also provide a more stable microenvironment in which the conjugative pilus can establish and maintain contact with recipient cells for the successful delivery of plasmid DNA. Furthermore, transfer in solid media may enhance the ability to transfer plasmids and chromosomes greater than 100 kbp. Using our optimized method, plasmids of varying sizes were tested for transfer from E. coli to S. cerevisiae. We demonstrated that there was no substantial decrease in conjugation frequency as plasmid size increased—up to 138.5 kbp in length. Finally, we established an efficient PCR-based synthesis protocol to generate custom conjugative plasmids

A twelve-week feeding trial was conducted to investigate the effect of dietary supplementation of a functional immunostimulant mixture (FIM; nucleotides, β-glucan and vitamins C and E) on growth, feed utilization, innate immunity, digestive enzyme activity, hematological parameters, intestinal morphology and inflammatory gene expression of olive flounder, Paralichthys olivaceus. A fish meal-based basal diet (control) was formulated and three other diets were prepared by incorporating 0.5, 1.0 and 1.5% FIM into the basal diet (HB0.5, HB1.0 and HB1.5, respectively). Five replicate groups of fish (26.3 ± 0.1 g) were fed one of the experimental diets. Inclusion of 1.5% FIM in the diet significantly enhanced growth and feed utilization. Significantly higher plasma hemoglobin, hematocrit, total protein levels and lower plasma glucose level were observed in HB1.5 group. Total immunoglobulin content, lysozyme, nitroblue tetrazolium, myeloperoxidase, superoxide dismutase, glutathione peroxidase and catalase activities and immune-related gene expressions of toll-like receptor and perforin were significantly increased at highest inclusion level. FIM supplementation significantly increased villus height and goblet cell counts. Anti-inflammatory gene expression was significantly upregulated at a 1.5% level. Dietary supplementation of 1.5% of FIM could improve growth and feed utilization, immune, hematological and histomorphological parameters of olive flounder.

Bioethanol has many environmental and practical benefits as a transportation fuel. It is one of the best alternatives to replace fossil fuels due to its liquid nature which is similar to petrol and diesel fuels traditionally used in transportation. In addition, bioethanol production technology has the capacity for negative carbon emissions which is vital for solving the current global warming dilemma. However, conventional bioethanol production takes place based on an inland site and relies on freshwater and edible crops (or land suitable for edible crop production) for production, which has led to the food vs fuel debate. Establishing a coastal marine biorefinery (CMB) system for bioethanol production that is based on coastal sites and relies on marine resources (seawater, marine biomass and marine yeast) could be the ultimate solution. In this paper, we aim to evaluate the environmental impact of using seawater for bioethanol production at coastal locations as a step towards the evaluation of a CMB system. Hence, a life cycle assessment for bioethanol production was conducted using the proposed scenario named Coastal-Seawater and compared to the conventional scenario, named Inland-Freshwater (IF). The impact of each scenario in relation to climate change, water depletion, land use and fossil depletion was studied for comparison. The coastal-seawater scenario demonstrated an improvement upon the conventional scenario in all the selected impact categories. In particular, the use of seawater in the process had a significant effect on water depletion showing an impact reduction of 31.2%. Furthermore, reductions are demonstrated in natural land transformation, climate change and fossil depletion of 5.5%, 3.5% and 4.2% respectively. This indicates the positive impact of using seawater and coastal locations for bioethanol production and encourages research to investigate the CMB system.

The use of interspecific hybrids during the industrial fermentation process has been well established, positioning the frontier of advancement in brewing to capitalize on the potential of Saccharomyces hybridization. Interspecific yeast hybrids used in modern monoculture inoculations benefit from a wide range of volatile metabolites that broaden the organoleptic complexity. This is the first report of sake brewing by Saccharomyces arboricola and its hybrids. S. arboricola x S. cerevisiae direct-mating generated cryotolerant interspecific hybrids which increased yields of ethanol and ethyl hexanoate compared to parental strains, important flavor attributes of fine Japanese ginjo sake rice wine. We used hierarchical clustering heatmapping with principal component analysis for metabolic profiling and found that the low levels of endogenous amino/organic acids clustered S. arboricola apart from the S. cerevisiae industrial strains. In sake fermentations, hybrid strains showed a mosaic profile of parental strains, while metabolic analysis suggested S. arboricola had a lower amino acid net uptake than S. cerevisiae. Additionally, we found an increase in ethanolic fermentation from pyruvate and increased sulfur metabolism. Together, our results suggest S. arboricola is poised for in-depth metabolomic exploration in sake fermentation.

Between a vineyard and the foliage wall of an adjacent forest, 25 traps containing different Drosophila attractants were applied on three occasions in autumn after the grape harvest. The attractant liquid was Pinot Blanc grape juice to which pure Saccharomyces cerevisiae yeast had been added to initiate fermentation. The five test variants differed in only one characteristic, namely the fermentation time, which was changed in two-day steps. Nine species of the genus Drosophila were captured, but only two were abundant enough to allow statistical analysis of variant differences in capture frequencies. Both species, D. suzukii and D. simulans, can affect the quality of the berries and ultimately the wine even before the harvest and are therefore considered pests. The studies showed that fermenting grape juice is significantly more attractive to both species than unfermented grape juice and that the attractiveness of the attractant liquid is maximised for D. simulans males with a fermentation time of seven to eight days.Parallel to this experiment, an analysis of the aroma spectrum of the fermenting grape juice was carried out with a temporal resolution of one day for the first twenty days. This made it possible to identify the aroma substances that had the highest concentrations in the time frame in which the attractant was particularly attractive and whose attractant effect should therefore be investigated further.

In eukaryotes, the Dph1•Dph2 dimer is a non-canonical radical SAM enzyme. Using iron-sulfur (FeS) clusters, it cleaves the cosubstrate S-adenosyl-methionine (SAM) to form a 3-amino-3-carboxy-propyl (ACP) radical for synthesis of diphthamide. The latter decorates a histidine residue on elongation factor 2 (EF2) conserved from archaea to yeast and humans and is important for accurate mRNA translation and protein synthesis. Guided by evidence from archaeal orthologues, we searched for a putative SAM binding pocket in Dph1•Dph2 from Saccharomyces cerevisiae. We predict a SAM binding pocket near the FeS cluster domain that is conserved across eukaryotes in Dph1 but not Dph2. Site-directed DPH1 mutagenesis and functional characterization by assays diagnostic for loss of diphthamide reveal the SAM pocket is essential for synthesis of the décor on EF2 in vivo. Further evidence from structural modeling suggests particularly critical residues close to the methionine moiety of SAM. Presumably, they facilitate a geometry specific for SAM cleavage and ACP radical formation that distinguishes Dph1•Dph2 from classical radical SAM enzymes, which generate canonical 5′-deoxyadenosyl (dAdo) radicals.

This study evaluated the anti-inflammatory effects, protection of gut barrier integrity, and stimulation of phagocytosis in peripheral cells of a nutritional supplement based on a synergistic combination of yeast-based ingredients with a unique 1,3/1,6-glucan complex and a consortium of postbiotic Saccharomyces cerevisiae rich in selenium and zinc. The anti-inflammatory effect in Caco-2 cells in the presence and absence of a pro-inflammatory challenge (tumour necrosis factor alpha [TNF-α]/interferon gamma [IFN-ɣ]) showed statistically significant reductions of IFN-ɣ induced protein-10 (IP-10), and monocyte chemoattractant protein-1 (MCP-1) levels vs. controls (p &lt; 0.001). Disruption of the gut integrity in the presence or absence of Escherichia coli (ETEC H10407) showed transepithelial electrical resistance (TEER) values higher in the ABB C1® group after 6 hours of testing. Spontaneous build-up of the gut epithelium monolayer over 22 days was also greater in the ABB C1® condition vs. a negative control. ABB C1® showed a significantly higher capacity to stimulate phagocytosis as compared with controls of algae β-1,3-glucan and yeast β-1,3/1,6 glucan (p &lt; 0.001). This study supports the mechanism of action by which ABB C1® may improve the immune response and be useful to prevent infection and allergy in clinical practice.

Saccharomyces cerevisiae are a phenotypically diverse species that adapt to a wide variety of environments by exploiting standing genetic diversity and selecting for advantageous mutations. Glyphosate and copper-based herbicides/ fungicides affect non-target organisms, these incidental exposures can impact microbial populations. In this study, glyphosate resistance was found in the historical collection of yeast which was collected over the last century, but only in yeast isolated after the introduction of glyphosate. The highest glyphosate-resistant yeasts were isolated from agricultural sites. However, herbicide application at these sites was not recorded. In an effort to assess glyphosate resistance and impact on non-target microorganisms, yeast were harvested from 15 areas with known herbicidal histories, including an organic farm, conventional farm, remediated coal mine, suburban locations, state park, and a national forest. Yeast representing 23 genera were isolated from 237 samples of plant, soil, spontaneous fermentation, nut, flower, fruit, feces, and tree material samples. Saccharomyces, Candida, Metschnikowia, Klyveromyces, Hanseniaspora, and Pichia were other genera commonly found across our sampled environments. Managed areas had less species diversity and at the brewery, only Saccharomyces and Pichia were isolated. A conventional farm growing RoundUp Ready™ corn had the lowest phylogenetic diversity and the highest glyphosate resistance. The mine was sprayed with multiple herbicides including a commercial formulation of glyphosate; however, the yeast did not have elevated glyphosate resistance. In contrast to the conventional farm, the mine was exposed to glyphosate only one year prior to sample isolation. Glyphosate resistance is an example of the anthropogenic selection of nontarget organisms.

The turnover of the RNA molecules is determined by the rates of transcription and RNA degradation. Several methods have been developed to study mRNA turnover since the beginnings of molecular biology. Here we summarize the main methods to measure RNA half-life: transcription inhibition, gene control and metabolic labelling. These methods were used to detect the cellular activity of the mRNAs degradation machinery, including the exo-ribonuclease Xrn1 and the exosome. Less progress has been made in the study of the differential stability of mature RNAs because the different methods have often yielded inconsistent results so that an mRNA considered to be stable can be classified as unstable by another method. Recent advances in the systematic comparison of different method variants in yeast have permitted the identification of the least invasive methodologies that reflect half-lives the most faithfully, which is expected to open the way for a consistent quantitative analysis of the determinants of mRNA stability.

RNA pol II assembly occurs in the cytoplasm before the translocation of the enzyme to the nucleus. Affecting assembly influences mRNA transcription in the nucleus and mRNA decay in the cytoplasm. However, very little is known about the consequences on ncRNA synthesis. In this work, we show that impairment of RNA pol II assembly leads to a decrease in cryptic non-coding RNAs (preferentially CUTs and SUTs). This alteration is partially restored upon overcoming the assembly defect. Notably, this drop in ncRNAs is only partially dependent on the nuclear exosome, which suggests a major specific effect of enzyme assembly. Our data also point out a defect in transcription termination and lead as to proposes that CTD phosphatase Rtr1 could be involved in this process.

The regulation of intracellular pH in yeast (Saccharomyces cerevisiae) cells is critical for cell function and viability. In yeast, protons (H+) can be excreted from cell by the plasma membrane ATPase Pma1 and pumped into vacuoles by the vacuolar H+-ATPase. Because Pma1 is critical to the survival of yeast cells, it is unknown whether other compensatory components are involved in the pH homeostasis in the absence of Pma1. To elucidate how intracellular pH is regulated independently of Pma1, we employed a screening approach by exposing the yeast haploid deletion mutant library (ver 4.0) to the selective plant plasma membrane H+-ATPase inhibitor PS-1, which we previously reported. After repeated screenings and verification, we identified two proteins, ALY1 and ALY2, that play a role in the regulation of intracellular pH when Pma1 is deficient. Our research uncovers a new perspective on the regulation of intracellular pH related to Pma1 and also preliminarily reveals a role for ALY1 and ALY2 in the regulation of intracellular pH.

Kluyveromyces marxianus (K. marxianus) is a newly emerging industrially relevant yeast. It is known to possess a highly efficient Non-Homologous End Joining (NHEJ) pathway that promotes random integration of non-homologous DNA fragments into its genome. The nature of the integration events was traditionally analyzed by Southern blot hybridization. However, the precise DNA sequence at the insertion sites were not fully explored. We transformed a PCR product of the Saccharomyces cerevisiae URA3 gene (ScURA3) into an uracil auxotroph K. marxianus wildtype strain and picked 24 stable Ura+ transformants for sequencing analysis. We took advantage of rapid advances in DNA sequencing technologies and developed a method using a combination of Illumina MiSeq and Oxford Nanopore sequencing. This approach enables us to uncover the Gross Chromosomal Rearrangements (GCRs) that are associated with the ScURA3 random integration. Moreover, it will shine a light on understanding DNA repair mechanisms in Eukaryotes, which could potentially provide insights for cancer research.

The Dph1•Dph2 heterodimer from yeast is a radical SAM (RS) enzyme that generates the 3-amino-3-carboxy-propyl (ACP) precursor for diphthamide, a clinically relevant modification on eukaryotic elongation factor 2 (eEF2). ACP formation requires SAM cleavage and atypical Cys-bound Fe-S clusters in each Dph1 and Dph2 subunit. Intriguingly, the first Cys residue in each motif locates next to another, ill-defined cysteine that we show in-here is conserved across eukaryotes. As judged from structural modeling, the orientation of these tandem cysteine motifs (TCM) suggests a candidate Fe-S cluster ligand role. Hence, we generated by site-directed DPH1 and DPH2 mutagenesis, Dph1•Dph2 variants with cysteines from each TCM replaced individually or in combination by serines. Assays diagnostic for diphthamide formation in vivo reveal that while single substitutions in the TCM of Dph2 cause mild defects, double mutations almost entirely inactivate the RS enzyme. Based on enhanced Dph1 and Dph2 subunit instability in response to cycloheximide chases, the variants with Cys substitutions in their cofactor motifs are particularly prone to protein degradation. In sum, we identify a fourth functionally cooperative Cys residue within the Fe-S motif of Dph2 and show that the Cys-based cofactor binding motifs in Dph1 and Dph2 are critical for the structural integrity of the dimeric RS enzyme in vivo.

We are all similar, but a bit different. These differences are partially due to variations in our genomes and are related to the heterogeneity of symptoms and responses to treatments that patients exhibit. Most animal studies are performed in one single strain with one manipulation. However, due to the lack of variability, therapies are not always reproducible when treatments are translated to humans. Panels of already sequenced organisms are valuable tools for mimicking human phenotypic heterogeneities and gene mapping. This review summarizes the current knowledge of mouse, fly and yeast panels with insightful applications for translational research.

Reversed Flow Gas Chromatography (R.F.G.C.) was employed to assess the impact of genetic modification on Saccharomyces cerevisiae yeast strains during the process of alcoholic fermentation, utilizing fig syrup. Multiple fermentations were carried out at various temperatures to evaluate the influence of genetic modifications on yeast strain efficiency. The study involved a wild-type yeast strain, W303, as a control, and two genetically modified strains, W_M4_533 and W_M4_558, sharing the same genetic background as the wild type. Notably, the genetic modifications in the Msn4p transcription factor involved the substitution of serine residues with alanine at positions 533 and 558, resulting in the development of psychrophilic or ethanol-resistant strains. Utilizing the R.F.G.C. method enabled the differentiation of the duration of alcoholic fermentation phases, providing insights correlated to the yeast cell life cycle. The values of rate constants (k) for each phase, conducted with both wild-type and genetically modified cells using RFGC, aligned with existing literature. Additionally, the calculation of activation energies for distinct phases revealed lower values for genetically modified strains compared to wild-type strains. This decrease in activation energies suggests enhanced efficiency in the alcoholic fermentation process for the genetically modified strains.