Catarina Prista - Academia.edu (original) (raw)

Papers by Catarina Prista

Research paper thumbnail of Use of European pulses to produce functional beverages – From chickpea and lupin as dairy alternatives

Journal of Functional Foods, Nov 1, 2022

Research paper thumbnail of Prospecting for l-arabinose/d-xylose symporters from Pichia guilliermondii and Aureobasidium leucospermi

Brazilian Journal of Microbiology, Sep 4, 2019

With the strong trend toward sustainable technologies, such as the gradual substitution of fossil... more With the strong trend toward sustainable technologies, such as the gradual substitution of fossil fuel consumption, improvement in the utilization of sugars from lignocellulosic biomass appears to be an alternative for bioenergy. However, from a number of C 5 sugars, few are used in fermentative processes for ethanol production. One of the reasons is because wild-type Saccharomyces cerevisiae is unable to efficiently co-utilize hexoses and pentoses via specific transporters for each type of sugar. Thus, a system of pentose uptake that is not modulated by D-glucose is required. Here, we were able to identify the presence of sugar/H + symporters for D-xylose and L-arabinose, especially for Pichia guilliermondii, where an uptake of D-glucose via symporter was not detected. The best D-xylose uptake route in P. guilliermondii exhibited a K M of 48 mM and V MAX of 0.48 mmol h −1 g −1 at the early stationary phase (24 h). For L-arabinose, the best route of uptake exhibited a K M of 109 mM and V MAX of 0.8 mmol h −1 g −1 on log phase (12 h). The highest kinetic uptake was observed when the final pH of the medium was below 7. In general, an alkaline medium limited the expression of symporters. The results obtained in this study will help in the further investigation of these symporters through their overexpression in engineered S. cerevisiae.

Research paper thumbnail of Application of the CATA methodology with children: Qualitative approach on ballot development and product characterization of innovative products

Food Quality and Preference, Mar 1, 2021

There is an increasing importance of the role of children and adolescents in the food market and ... more There is an increasing importance of the role of children and adolescents in the food market and to successfully develop food products intended for them, it is necessary to apply proper sensory evaluation methodologies. Although children can execute traditional methods for food liking and preference evaluation, traditional sensory descriptive methods may not be suitable for them and it is necessary to assess their ability to perform novel sensory profiling methods. Thus, this study aimed to assess children's acceptance of an innovative food productcookies incorporating fermented grass pea (Lathyrus sativus) flourand their ability to describe a sensory profile using a Check-All-That-Apply (CATA) approach. Two different types of cookies (salty and sweet) were developed, differing in the level of substitution of wheat flour by fermented grass pea flour (between 0 and 40%). The cookies were evaluated by two sensory panels of 60 children (8-12 years), who assessed the overall liking using a 7-point facial hedonic scale and the sensory profile of the samples using a CATA ballot with 21 sensory terms previously developed through focus groups with children. Children showed the ability to discriminate the different samples with the hedonic scale and according to their sensory profile. Results revealed that the focusgroup with children is an adequate way to generate CATA ballots and that the CATA approach is adequate to evaluate how children discriminate the sensory profile of food products. Furthermore, the food neophobia level of the children negatively impacted their acceptance of the food products.

Research paper thumbnail of Improving chestnut physicochemical properties through fermentation – Development of chestnut Amazake

Food Chemistry: X, Mar 1, 2023

Research paper thumbnail of The importance, prevalence and determination of vitamins B6 and B12 in food matrices: A review

Food Chemistry, Nov 1, 2023

Research paper thumbnail of Molecular and Functional Characterization of Grapevine NIPs through Heterologous Expression in aqy-Null Saccharomyces cerevisiae

International Journal of Molecular Sciences, Jan 19, 2020

Plant Nodulin 26-like Intrinsic Proteins (NIPs) are multifunctional membrane channels of the Majo... more Plant Nodulin 26-like Intrinsic Proteins (NIPs) are multifunctional membrane channels of the Major Intrinsic Protein (MIP) family. Unlike other homologs, they have low intrinsic water permeability. NIPs possess diverse substrate selectivity, ranging from water to glycerol and to other small solutes, depending on the group-specific amino acid composition at aromatic/Arg (ar/R) constriction. We cloned three NIPs (NIP1;1, NIP5;1, and NIP6;1) from grapevine (cv. Touriga Nacional). Their expression in the membrane of aqy-null Saccharomyces cerevisiae enabled their functional characterization for water and glycerol transport through stopped-flow spectroscopy. VvTnNIP1;1 demonstrated high water as well as glycerol permeability, whereas VvTnNIP6;1 was impermeable to water but presented high glycerol permeability. Their transport activities were declined by cytosolic acidification, implying that internal-pH can regulate NIPs gating. Furthermore, an extension of C-terminal in VvTnNIP6;1M homolog, led to improved channel activity, suggesting that NIPs gating is putatively regulated by C-terminal. Yeast growth assays in the presence of diverse substrates suggest that the transmembrane flux of metalloids (As, B, and Se) and the heavy metal (Cd) are facilitated through grapevine NIPs. This is the first molecular and functional characterization of grapevine NIPs, providing crucial insights into understanding their role for uptake and translocation of small solutes, and extrusion of toxic compounds in grapevine.

Research paper thumbnail of Tomate Verde Fermentado: Uma Via para a Sustentabilidade Económica e Ambiental

Boletim da Sociedade Portuguesa de Química, Jun 30, 2022

Research paper thumbnail of Development and physicochemical characterization of a new grass pea ( Lathyrus sativus L.) miso

Journal of the Science of Food and Agriculture, Oct 20, 2020

BACKGROUND: Western consumers interest in Eastern fermented foods has been growing, due to their ... more BACKGROUND: Western consumers interest in Eastern fermented foods has been growing, due to their nutritional and healthy properties. In this study, new sweet misos and salty misos were produced using grass pea (Lathyrus sativus L.)traditional Portuguese legume from local producersto promote its consumption and preservation. The evolution of the new misos was evaluated in comparison to traditional miso (made from soybean), through analysis of the chemical composition, colour, texture and linear viscoelastic behaviour. RESULTS: Throughout the fermentation process, the ascorbic acid and phenolic compounds contentwith important nutritional valueincreased in all misos, mainly in misos produced using grass pea, besides, grass pea sweet miso presented the fastest evolution and darkest colour. The texture parameters (firmness and adhesiveness) of misos decreased over time: grass pea sweet miso showed the highest firmness reduction (51.63 N to 6.52 N) and soybean sweet miso the highest adhesiveness reduction (27.76 N to 3.11 N). Viscoelastic moduli also decreased, reflecting a reduction in the degree of internal structuring for all misos. However, grass pea misos presented more structured internal systems with faster maturation kinetics than soybean misos, for which stabilization started earlier. CONCLUSION: Two innovative misos were developed from grass pea. After 4 months, the texture parameters and viscoelastic moduli for grass pea misos, were similar to the control misos made from soybean, showing that grass pea can be used as a raw material to produce a sustainable miso with potentially healthy properties.

Research paper thumbnail of Genes from increase salt tolerance in W303

Fems Yeast Research, May 1, 2002

The yeast Debaryomyces hansenii has been chosen as a model for molecular studies of tolerance to ... more The yeast Debaryomyces hansenii has been chosen as a model for molecular studies of tolerance to NaCl. A gene library was built and transformants of Saccharomyces cerevisiae W303 containing genes from D. hansenii were selected for their ability to grow in the presence of high concentrations of NaCl and/or low concentrations of KCl. In three of these transformants 500 mM

Research paper thumbnail of The grapevine NIP2;1 aquaporin is a silicon channel

Journal of Experimental Botany, 2020

Silicon (Si) supplementation has been shown to improve plant tolerance to different stresses, and... more Silicon (Si) supplementation has been shown to improve plant tolerance to different stresses, and its accumulation in the aerial organs is mediated by NIP2;1 aquaporins (Lsi channels) and Lsi2-type exporters in roots. In the present study, we tested the hypothesis that grapevine expresses a functional NIP2;1 that accounts for root Si uptake and, eventually, Si accumulation in leaves. Own-rooted grapevine cuttings of the cultivar Vinhão accumulated >0.2% Si (DW) in leaves when irrigated with 1.5 mM Si for 1 month, while Si was undetected in control leaves. Real-time PCR showed that VvNIP2;1 was highly expressed in roots and in green berries. The transient transformation of tobacco leaf epidermal cells mediated by Agrobacterium tumefaciens confirmed VvNIP2;1 localization at the plasma membrane. Transport experiments in oocytes showed that VvNIP2;1 mediates Si and arsenite uptake, whereas permeability studies revealed that VvNIP2;1 expressed in yeast is unable to transport water and...

Research paper thumbnail of Exploring the gating mechanisms of aquaporin-3: new clues for the design of inhibitors?

Molecular BioSystems, 2016

The pH gating of human AQP3 and its effects on both water and glycerol permeabilities have been f... more The pH gating of human AQP3 and its effects on both water and glycerol permeabilities have been fully characterized for the first time using a human red blood cell model (hRBC).

Research paper thumbnail of Fermented unripe tomato paste – Development of innovative salad dressings as a contribution to circular economy

Food Science and Technology International

As food trends evolve towards sustainable, healthy, and mildly processed products, it is essentia... more As food trends evolve towards sustainable, healthy, and mildly processed products, it is essential to consider new food sources, which contribute to positive changes in the food industry and originate interesting new products. For the tomato industry, where only completely red tomatoes are used, unripe and non-red tomatoes constitute an important by-product, with important losses in the field of a perfectly edible vegetable food source. To give value to this unripe tomato, a fermentation with a consortium of lactic acid bacteria and yeast was previously optimized, originating an acidic pulp with optimized nutritional characteristics and great potential for salad dressing development. Pulp's texture was improved with two hydrocolloid systems: 0.5 g/100 g of xanthan gum; and a mixed system of xanthan gum and kappa-carrageenan (0.1 g/100 g each). After rheology optimization, spices and condiments were added to the thickened fermented pulp, and promising tasty sauces were obtained. ...

Research paper thumbnail of Role of p-Coumaric Acid and Micronutrients in Sulfur Dioxide Tolerance in Brettanomyces bruxellensis

Beverages

Sulfite is a common preservative in wine, but the spoilage yeast Brettanomyces bruxellensis can p... more Sulfite is a common preservative in wine, but the spoilage yeast Brettanomyces bruxellensis can produce volatile phenols even with the recommended sulfite dose. The purpose of this study was to examine how wine components, p-coumaric acid (a precursor of volatile phenols), and micronutrients influence culturability, viability, and volatile phenols production by B. bruxellensis under sulfite stress. In red wine, a high sulfite dose (potassium metabisulfite, 100 mg L−1) led to an immediate death phase followed by growth recovery after two weeks. However, 4-ethylphenol (4-EP) was continuously produced by dead or nonculturable cells. Nonetheless, an event of growth recovery could not be observed in the case of the model wine. However, when the model wine was supplemented with minerals and vitamins, both growth recovery and 4-EP production were noticed, suggesting that the minerals and vitamins played an important role in maintaining the viability of cells under the sulfite stress. The y...

Research paper thumbnail of Functional characterization of PIP and TIP grapevine aquaporins by heterologous expression in Saccharomyces cerevisiae

ABSTRACT Molecular cloning of aquaporins PIP1;4/PIP2;1/PIP2;3 and TIP1;1/TIP2;2/TIP4;1 from V. vi... more ABSTRACT Molecular cloning of aquaporins PIP1;4/PIP2;1/PIP2;3 and TIP1;1/TIP2;2/TIP4;1 from V. vinifera (cv. Touriga nacional) and its heterologous expression in aqy-null S. cerevisiae were attempted. Their membrane localization was confirmed by GFP-tagging. These aquaporins were individually characterized for water transport [Activation energy (Ea) and water permeability coefficient (Pf)] by stopped flow spectroscopy. PIP2;1/TIP1;1/TIP2;2 actively transported water with lower Ea (9.8±0.3, 8.9±0.2, 9.25±0.2 kcalmol-1) and higher Pf (4.8±0.5, 5.16±0.1, 4.54±0.2 cms-1) than the host strain (Ea=15.0±0.2 kcalmol-1, Pf=2.23±0.07cms-1). PIP1;4/PIP2;3/TIP4;1 were non-functional for water transport with almost equal Ea and Pf values as the host strain. Growth assays suggest that PIP2;3/PIP2;2/TIP2;1/TIP4;1 are putative transporters for H2O2 and PIP2;1/TIP1;1/TIP4;1 exhibited transport of boron. All PIPs/TIPs showed high sensitivity under chloride, that infers their involvement in chloride transport.

Research paper thumbnail of The osmotolerant fructophilic yeast Zygosaccharomyces rouxii employs two plasma-membrane fructose uptake systems belonging to a new family of yeast sugar transporters

Microbiology, 2011

Owing to its high resistance to weak-acid preservatives and extreme osmotolerance, Zygosaccharomy... more Owing to its high resistance to weak-acid preservatives and extreme osmotolerance, Zygosaccharomyces rouxii is one of the main spoilage yeasts of sweet foods and beverages. In contrast with Saccharomyces cerevisiae, Z. rouxii is a fructophilic yeast; it consumes fructose faster than glucose. So far, to our knowledge, no specific Z. rouxii proteins responsible for this fructophilic behaviour have been characterized. We have identified two genes encoding putative fructose transporters in the Z. rouxii CBS 732 genome. Heterologous expression of these two Z. rouxii ORFs in a S. cerevisiae strain lacking its own hexose transporters (hxt-null) and subsequent kinetic analysis of sugar transport showed that both proteins are functionally expressed at the plasma membrane: ZrFfz1 is a high-capacity fructose-specific facilitator (K m~4 00 mM and V max~1 3 mmol h "1 g "1 ) and ZrFfz2 is a facilitator transporting glucose and fructose with similar capacity and affinity (K m~2 00 mM and V max~4 mmol h "1 g "1 ). These two proteins together with the Zygosaccharomyces bailii Ffz1 fructose-specific transporter belong to a new family of sugar transport systems mediating the uptake of hexoses via the facilitated diffusion mechanism, and are more homologous to drug/H + antiporters (regarding their primary protein structure) than to other yeast sugar transporters of the Sugar Porter family.

Research paper thumbnail of Yeast water channels: an overview of orthodox aquaporins

Biology of the Cell, 2011

In yeast, the presence of orthodox aquaporins has been first recognized in Saccharomyces cerevisi... more In yeast, the presence of orthodox aquaporins has been first recognized in Saccharomyces cerevisiae, in which two genes (AQY1 and AQY2) were shown to be related to mammal and plant water channels. The present review summarizes the putative orthodox aquaporin protein sequences found in available genomes of yeast and filamentous fungi. Among the 28 yeast genomes sequenced, most species present only one orthodox aquaporin, and no aquaporins were found in eight yeast species. Alignment of amino acid sequences reveals a very diverse group. Similarity values vary from 99 % among species within the Saccharomyces genus to 34 % between ScAqy1 and the aquaporin from Debaryomyces hansenii. All of the fungal aquaporins possess the known characteristic sequences, and residues involved in the water channel pore are highly conserved. Advances in the establishment of the structure are reviewed in relation to the mechanisms of selectivity, conductance and gating. In particular, the involvement of the protein cytosolic N-terminus as a channel blocker preventing water flow is addressed. Methodologies used in the evaluation of aquaporin activity frequently involve the measurement of fast volume changes. Particular attention is paid to data analysis to obtain accurate membrane water permeability parameters. Although the presence of aquaporins clearly enhances membrane water permeability, the relevance of these ubiquitous water channels in yeast performance remains obscure.

Research paper thumbnail of Physiological Basis for the High Salt Tolerance of Debaryomyces hansenii

than in S. cerevisiae. In media with low K1 ,N a 1was able to substitute for K1, restoring the sp... more than in S. cerevisiae. In media with low K1 ,N a 1was able to substitute for K1, restoring the specific growth rate and the final biomass of the culture. The intracellular concentration of Na1 reached values up to 800 mM, suggesting that metabolism is not affected by rather high concentrations of salt. The ability of D. hansenii to extrude Na1

Research paper thumbnail of Efficient fermentation of an improved synthetic grape must by enological and laboratory strains of Saccharomyces cerevisiae

AMB Express, 2014

Grape must or freshly pressed grape juice is a complex chemical matrix that impacts the efficienc... more Grape must or freshly pressed grape juice is a complex chemical matrix that impacts the efficiency of yeast fermentation. The composition of natural grape must (NGM) can be variable; thus, to ensure reproducibility, a synthetic grape must (SGM) with defined composition is commonly used. The aim of this work was to create conditions to advance the use of Saccharomyces cerevisiae laboratory strains for wine fermentation studies, considering previous results obtained for enological strains fermenting NGM under simulated winery conditions. We designed a new SGM formulation, ISA-SGM, by introducing specific modifications to a commonly used formulation, putting together previous reports. We added glucose and fructose in equal amounts (125 g/l) and 50 parts per million (ppm) sulfur dioxide (SO 2, corresponding to standard enological treatment), and we optimized the concentrations of malic acid (3 g/l), citric acid (0.3 g/l), and tartaric acid (3 g/l). Using ISA-SGM, we obtained similar fermentative profiles for the wine strain ISA1000, the prototrophic strain S288C, and its auxotrophic derivative BY4741. In this case, the concentrations of supplements were optimized to 120 mg/l L-uracil, 80 mg/l L-methionine, 400 mg/l L-leucine, and 100 mg/l L-histidine. All these strains tested in ISA-SGM presented a similar fermentative performance as ISA1000 in NGM. ISA-SGM formulation is a promising new tool to allow the use of the auxotrophic BY strains in the detailed assessment of the alcoholic fermentation process under simulated winery conditions, and it provides a foundation to extract relevant physiological conclusions in future research on enological yeast traits.

Research paper thumbnail of The high capacity specific fructose facilitator ZrFfz1 is essential for the fructophilic behavior of Zygosaccharomyces rouxii CBS 732T

Eukaryotic Cell, 2014

Zygosaccharomyces rouxii is a fructophilic yeast that consumes fructose preferably to glucose. Th... more Zygosaccharomyces rouxii is a fructophilic yeast that consumes fructose preferably to glucose. This behavior seems to be related to sugar uptake. In this study, we constructed Z. rouxii single-, double-, and triple-deletion mutants in the UL4 strain background (a ura3 strain derived from CBS 732 T ) by deleting the genes encoding the specific fructose facilitator Z. rouxii Ffz1 (ZrFfz1), the fructose/glucose facilitator ZrFfz2, and/or the fructose symporter ZrFsy1. We analyzed the effects on the growth phenotype, on kinetic parameters of fructose and glucose uptake, and on sugar consumption profiles. No growth phenotype was observed on fructose or glucose upon deletion of FFZ genes. Deletion of ZrFFZ1 drastically reduced fructose transport capacity, increased glucose transport capacity, and eliminated the fructophilic character, while deletion of ZrFFZ2 had almost no effect. The strain in which both FFZ genes were deleted presented even higher consumption of glucose than strain Zrffz1⌬, probably due to a reduced repressing effect of fructose. This study confirms the molecular basis of the Z. rouxii fructophilic character, demonstrating that ZrFfz1 is essential for Z. rouxii fructophilic behavior. The gene is a good candidate to improve the fructose fermentation performance of industrial Saccharomyces cerevisiae strains.

Research paper thumbnail of Exploring Three PIPs and Three TIPs of Grapevine for Transport of Water and Atypical Substrates through Heterologous Expression in aqy-null Yeast

PLoS ONE, 2014

Aquaporins are membrane channels that facilitate the transport of water and other small molecules... more Aquaporins are membrane channels that facilitate the transport of water and other small molecules across the cellular membranes. We examined the role of six aquaporins of Vitis vinifera (cv. Touriga nacional) in the transport of water and atypical substrates (other than water) in an aqy-null strain of Saccharomyces cerevisiae. Their functional characterization for water transport was performed by stopped-flow fluorescence spectroscopy. The evaluation of permeability coefficients (Pf) and activation energies (Ea) revealed that three aquaporins (VvTnPIP2;1, VvTnTIP1;1 and VvTnTIP2;2) are functional for water transport, while the other three (VvTnPIP1;4, VvTnPIP2;3 and VvTnTIP4;1) are non-functional. TIPs (VvTnTIP1;1 and VvTnTIP2;2) exhibited higher water permeability than VvTnPIP2;1. All functional aquaporins were found to be sensitive to HgCl2, since their water conductivity was reduced (24-38%) by the addition of 0.5 mM HgCl2. Expression of Vitis aquaporins caused different sensitive phenotypes to yeast strains when grown under hyperosmotic stress generated by KCl or sorbitol. Our results also indicate that Vitis aquaporins are putative transporters of other small molecules of physiological importance. Their sequence analyses revealed the presence of signature sequences for transport of ammonia, boron, CO2, H2O2 and urea. The phenotypic growth variations of yeast cells showed that heterologous expression of Vitis aquaporins increased susceptibility to externally applied boron and H2O2, suggesting the contribution of Vitis aquaporins in the transport of these species.

Research paper thumbnail of Use of European pulses to produce functional beverages – From chickpea and lupin as dairy alternatives

Journal of Functional Foods, Nov 1, 2022

Research paper thumbnail of Prospecting for l-arabinose/d-xylose symporters from Pichia guilliermondii and Aureobasidium leucospermi

Brazilian Journal of Microbiology, Sep 4, 2019

With the strong trend toward sustainable technologies, such as the gradual substitution of fossil... more With the strong trend toward sustainable technologies, such as the gradual substitution of fossil fuel consumption, improvement in the utilization of sugars from lignocellulosic biomass appears to be an alternative for bioenergy. However, from a number of C 5 sugars, few are used in fermentative processes for ethanol production. One of the reasons is because wild-type Saccharomyces cerevisiae is unable to efficiently co-utilize hexoses and pentoses via specific transporters for each type of sugar. Thus, a system of pentose uptake that is not modulated by D-glucose is required. Here, we were able to identify the presence of sugar/H + symporters for D-xylose and L-arabinose, especially for Pichia guilliermondii, where an uptake of D-glucose via symporter was not detected. The best D-xylose uptake route in P. guilliermondii exhibited a K M of 48 mM and V MAX of 0.48 mmol h −1 g −1 at the early stationary phase (24 h). For L-arabinose, the best route of uptake exhibited a K M of 109 mM and V MAX of 0.8 mmol h −1 g −1 on log phase (12 h). The highest kinetic uptake was observed when the final pH of the medium was below 7. In general, an alkaline medium limited the expression of symporters. The results obtained in this study will help in the further investigation of these symporters through their overexpression in engineered S. cerevisiae.

Research paper thumbnail of Application of the CATA methodology with children: Qualitative approach on ballot development and product characterization of innovative products

Food Quality and Preference, Mar 1, 2021

There is an increasing importance of the role of children and adolescents in the food market and ... more There is an increasing importance of the role of children and adolescents in the food market and to successfully develop food products intended for them, it is necessary to apply proper sensory evaluation methodologies. Although children can execute traditional methods for food liking and preference evaluation, traditional sensory descriptive methods may not be suitable for them and it is necessary to assess their ability to perform novel sensory profiling methods. Thus, this study aimed to assess children's acceptance of an innovative food productcookies incorporating fermented grass pea (Lathyrus sativus) flourand their ability to describe a sensory profile using a Check-All-That-Apply (CATA) approach. Two different types of cookies (salty and sweet) were developed, differing in the level of substitution of wheat flour by fermented grass pea flour (between 0 and 40%). The cookies were evaluated by two sensory panels of 60 children (8-12 years), who assessed the overall liking using a 7-point facial hedonic scale and the sensory profile of the samples using a CATA ballot with 21 sensory terms previously developed through focus groups with children. Children showed the ability to discriminate the different samples with the hedonic scale and according to their sensory profile. Results revealed that the focusgroup with children is an adequate way to generate CATA ballots and that the CATA approach is adequate to evaluate how children discriminate the sensory profile of food products. Furthermore, the food neophobia level of the children negatively impacted their acceptance of the food products.

Research paper thumbnail of Improving chestnut physicochemical properties through fermentation – Development of chestnut Amazake

Food Chemistry: X, Mar 1, 2023

Research paper thumbnail of The importance, prevalence and determination of vitamins B6 and B12 in food matrices: A review

Food Chemistry, Nov 1, 2023

Research paper thumbnail of Molecular and Functional Characterization of Grapevine NIPs through Heterologous Expression in aqy-Null Saccharomyces cerevisiae

International Journal of Molecular Sciences, Jan 19, 2020

Plant Nodulin 26-like Intrinsic Proteins (NIPs) are multifunctional membrane channels of the Majo... more Plant Nodulin 26-like Intrinsic Proteins (NIPs) are multifunctional membrane channels of the Major Intrinsic Protein (MIP) family. Unlike other homologs, they have low intrinsic water permeability. NIPs possess diverse substrate selectivity, ranging from water to glycerol and to other small solutes, depending on the group-specific amino acid composition at aromatic/Arg (ar/R) constriction. We cloned three NIPs (NIP1;1, NIP5;1, and NIP6;1) from grapevine (cv. Touriga Nacional). Their expression in the membrane of aqy-null Saccharomyces cerevisiae enabled their functional characterization for water and glycerol transport through stopped-flow spectroscopy. VvTnNIP1;1 demonstrated high water as well as glycerol permeability, whereas VvTnNIP6;1 was impermeable to water but presented high glycerol permeability. Their transport activities were declined by cytosolic acidification, implying that internal-pH can regulate NIPs gating. Furthermore, an extension of C-terminal in VvTnNIP6;1M homolog, led to improved channel activity, suggesting that NIPs gating is putatively regulated by C-terminal. Yeast growth assays in the presence of diverse substrates suggest that the transmembrane flux of metalloids (As, B, and Se) and the heavy metal (Cd) are facilitated through grapevine NIPs. This is the first molecular and functional characterization of grapevine NIPs, providing crucial insights into understanding their role for uptake and translocation of small solutes, and extrusion of toxic compounds in grapevine.

Research paper thumbnail of Tomate Verde Fermentado: Uma Via para a Sustentabilidade Económica e Ambiental

Boletim da Sociedade Portuguesa de Química, Jun 30, 2022

Research paper thumbnail of Development and physicochemical characterization of a new grass pea ( Lathyrus sativus L.) miso

Journal of the Science of Food and Agriculture, Oct 20, 2020

BACKGROUND: Western consumers interest in Eastern fermented foods has been growing, due to their ... more BACKGROUND: Western consumers interest in Eastern fermented foods has been growing, due to their nutritional and healthy properties. In this study, new sweet misos and salty misos were produced using grass pea (Lathyrus sativus L.)traditional Portuguese legume from local producersto promote its consumption and preservation. The evolution of the new misos was evaluated in comparison to traditional miso (made from soybean), through analysis of the chemical composition, colour, texture and linear viscoelastic behaviour. RESULTS: Throughout the fermentation process, the ascorbic acid and phenolic compounds contentwith important nutritional valueincreased in all misos, mainly in misos produced using grass pea, besides, grass pea sweet miso presented the fastest evolution and darkest colour. The texture parameters (firmness and adhesiveness) of misos decreased over time: grass pea sweet miso showed the highest firmness reduction (51.63 N to 6.52 N) and soybean sweet miso the highest adhesiveness reduction (27.76 N to 3.11 N). Viscoelastic moduli also decreased, reflecting a reduction in the degree of internal structuring for all misos. However, grass pea misos presented more structured internal systems with faster maturation kinetics than soybean misos, for which stabilization started earlier. CONCLUSION: Two innovative misos were developed from grass pea. After 4 months, the texture parameters and viscoelastic moduli for grass pea misos, were similar to the control misos made from soybean, showing that grass pea can be used as a raw material to produce a sustainable miso with potentially healthy properties.

Research paper thumbnail of Genes from increase salt tolerance in W303

Fems Yeast Research, May 1, 2002

The yeast Debaryomyces hansenii has been chosen as a model for molecular studies of tolerance to ... more The yeast Debaryomyces hansenii has been chosen as a model for molecular studies of tolerance to NaCl. A gene library was built and transformants of Saccharomyces cerevisiae W303 containing genes from D. hansenii were selected for their ability to grow in the presence of high concentrations of NaCl and/or low concentrations of KCl. In three of these transformants 500 mM

Research paper thumbnail of The grapevine NIP2;1 aquaporin is a silicon channel

Journal of Experimental Botany, 2020

Silicon (Si) supplementation has been shown to improve plant tolerance to different stresses, and... more Silicon (Si) supplementation has been shown to improve plant tolerance to different stresses, and its accumulation in the aerial organs is mediated by NIP2;1 aquaporins (Lsi channels) and Lsi2-type exporters in roots. In the present study, we tested the hypothesis that grapevine expresses a functional NIP2;1 that accounts for root Si uptake and, eventually, Si accumulation in leaves. Own-rooted grapevine cuttings of the cultivar Vinhão accumulated >0.2% Si (DW) in leaves when irrigated with 1.5 mM Si for 1 month, while Si was undetected in control leaves. Real-time PCR showed that VvNIP2;1 was highly expressed in roots and in green berries. The transient transformation of tobacco leaf epidermal cells mediated by Agrobacterium tumefaciens confirmed VvNIP2;1 localization at the plasma membrane. Transport experiments in oocytes showed that VvNIP2;1 mediates Si and arsenite uptake, whereas permeability studies revealed that VvNIP2;1 expressed in yeast is unable to transport water and...

Research paper thumbnail of Exploring the gating mechanisms of aquaporin-3: new clues for the design of inhibitors?

Molecular BioSystems, 2016

The pH gating of human AQP3 and its effects on both water and glycerol permeabilities have been f... more The pH gating of human AQP3 and its effects on both water and glycerol permeabilities have been fully characterized for the first time using a human red blood cell model (hRBC).

Research paper thumbnail of Fermented unripe tomato paste – Development of innovative salad dressings as a contribution to circular economy

Food Science and Technology International

As food trends evolve towards sustainable, healthy, and mildly processed products, it is essentia... more As food trends evolve towards sustainable, healthy, and mildly processed products, it is essential to consider new food sources, which contribute to positive changes in the food industry and originate interesting new products. For the tomato industry, where only completely red tomatoes are used, unripe and non-red tomatoes constitute an important by-product, with important losses in the field of a perfectly edible vegetable food source. To give value to this unripe tomato, a fermentation with a consortium of lactic acid bacteria and yeast was previously optimized, originating an acidic pulp with optimized nutritional characteristics and great potential for salad dressing development. Pulp's texture was improved with two hydrocolloid systems: 0.5 g/100 g of xanthan gum; and a mixed system of xanthan gum and kappa-carrageenan (0.1 g/100 g each). After rheology optimization, spices and condiments were added to the thickened fermented pulp, and promising tasty sauces were obtained. ...

Research paper thumbnail of Role of p-Coumaric Acid and Micronutrients in Sulfur Dioxide Tolerance in Brettanomyces bruxellensis

Beverages

Sulfite is a common preservative in wine, but the spoilage yeast Brettanomyces bruxellensis can p... more Sulfite is a common preservative in wine, but the spoilage yeast Brettanomyces bruxellensis can produce volatile phenols even with the recommended sulfite dose. The purpose of this study was to examine how wine components, p-coumaric acid (a precursor of volatile phenols), and micronutrients influence culturability, viability, and volatile phenols production by B. bruxellensis under sulfite stress. In red wine, a high sulfite dose (potassium metabisulfite, 100 mg L−1) led to an immediate death phase followed by growth recovery after two weeks. However, 4-ethylphenol (4-EP) was continuously produced by dead or nonculturable cells. Nonetheless, an event of growth recovery could not be observed in the case of the model wine. However, when the model wine was supplemented with minerals and vitamins, both growth recovery and 4-EP production were noticed, suggesting that the minerals and vitamins played an important role in maintaining the viability of cells under the sulfite stress. The y...

Research paper thumbnail of Functional characterization of PIP and TIP grapevine aquaporins by heterologous expression in Saccharomyces cerevisiae

ABSTRACT Molecular cloning of aquaporins PIP1;4/PIP2;1/PIP2;3 and TIP1;1/TIP2;2/TIP4;1 from V. vi... more ABSTRACT Molecular cloning of aquaporins PIP1;4/PIP2;1/PIP2;3 and TIP1;1/TIP2;2/TIP4;1 from V. vinifera (cv. Touriga nacional) and its heterologous expression in aqy-null S. cerevisiae were attempted. Their membrane localization was confirmed by GFP-tagging. These aquaporins were individually characterized for water transport [Activation energy (Ea) and water permeability coefficient (Pf)] by stopped flow spectroscopy. PIP2;1/TIP1;1/TIP2;2 actively transported water with lower Ea (9.8±0.3, 8.9±0.2, 9.25±0.2 kcalmol-1) and higher Pf (4.8±0.5, 5.16±0.1, 4.54±0.2 cms-1) than the host strain (Ea=15.0±0.2 kcalmol-1, Pf=2.23±0.07cms-1). PIP1;4/PIP2;3/TIP4;1 were non-functional for water transport with almost equal Ea and Pf values as the host strain. Growth assays suggest that PIP2;3/PIP2;2/TIP2;1/TIP4;1 are putative transporters for H2O2 and PIP2;1/TIP1;1/TIP4;1 exhibited transport of boron. All PIPs/TIPs showed high sensitivity under chloride, that infers their involvement in chloride transport.

Research paper thumbnail of The osmotolerant fructophilic yeast Zygosaccharomyces rouxii employs two plasma-membrane fructose uptake systems belonging to a new family of yeast sugar transporters

Microbiology, 2011

Owing to its high resistance to weak-acid preservatives and extreme osmotolerance, Zygosaccharomy... more Owing to its high resistance to weak-acid preservatives and extreme osmotolerance, Zygosaccharomyces rouxii is one of the main spoilage yeasts of sweet foods and beverages. In contrast with Saccharomyces cerevisiae, Z. rouxii is a fructophilic yeast; it consumes fructose faster than glucose. So far, to our knowledge, no specific Z. rouxii proteins responsible for this fructophilic behaviour have been characterized. We have identified two genes encoding putative fructose transporters in the Z. rouxii CBS 732 genome. Heterologous expression of these two Z. rouxii ORFs in a S. cerevisiae strain lacking its own hexose transporters (hxt-null) and subsequent kinetic analysis of sugar transport showed that both proteins are functionally expressed at the plasma membrane: ZrFfz1 is a high-capacity fructose-specific facilitator (K m~4 00 mM and V max~1 3 mmol h "1 g "1 ) and ZrFfz2 is a facilitator transporting glucose and fructose with similar capacity and affinity (K m~2 00 mM and V max~4 mmol h "1 g "1 ). These two proteins together with the Zygosaccharomyces bailii Ffz1 fructose-specific transporter belong to a new family of sugar transport systems mediating the uptake of hexoses via the facilitated diffusion mechanism, and are more homologous to drug/H + antiporters (regarding their primary protein structure) than to other yeast sugar transporters of the Sugar Porter family.

Research paper thumbnail of Yeast water channels: an overview of orthodox aquaporins

Biology of the Cell, 2011

In yeast, the presence of orthodox aquaporins has been first recognized in Saccharomyces cerevisi... more In yeast, the presence of orthodox aquaporins has been first recognized in Saccharomyces cerevisiae, in which two genes (AQY1 and AQY2) were shown to be related to mammal and plant water channels. The present review summarizes the putative orthodox aquaporin protein sequences found in available genomes of yeast and filamentous fungi. Among the 28 yeast genomes sequenced, most species present only one orthodox aquaporin, and no aquaporins were found in eight yeast species. Alignment of amino acid sequences reveals a very diverse group. Similarity values vary from 99 % among species within the Saccharomyces genus to 34 % between ScAqy1 and the aquaporin from Debaryomyces hansenii. All of the fungal aquaporins possess the known characteristic sequences, and residues involved in the water channel pore are highly conserved. Advances in the establishment of the structure are reviewed in relation to the mechanisms of selectivity, conductance and gating. In particular, the involvement of the protein cytosolic N-terminus as a channel blocker preventing water flow is addressed. Methodologies used in the evaluation of aquaporin activity frequently involve the measurement of fast volume changes. Particular attention is paid to data analysis to obtain accurate membrane water permeability parameters. Although the presence of aquaporins clearly enhances membrane water permeability, the relevance of these ubiquitous water channels in yeast performance remains obscure.

Research paper thumbnail of Physiological Basis for the High Salt Tolerance of Debaryomyces hansenii

than in S. cerevisiae. In media with low K1 ,N a 1was able to substitute for K1, restoring the sp... more than in S. cerevisiae. In media with low K1 ,N a 1was able to substitute for K1, restoring the specific growth rate and the final biomass of the culture. The intracellular concentration of Na1 reached values up to 800 mM, suggesting that metabolism is not affected by rather high concentrations of salt. The ability of D. hansenii to extrude Na1

Research paper thumbnail of Efficient fermentation of an improved synthetic grape must by enological and laboratory strains of Saccharomyces cerevisiae

AMB Express, 2014

Grape must or freshly pressed grape juice is a complex chemical matrix that impacts the efficienc... more Grape must or freshly pressed grape juice is a complex chemical matrix that impacts the efficiency of yeast fermentation. The composition of natural grape must (NGM) can be variable; thus, to ensure reproducibility, a synthetic grape must (SGM) with defined composition is commonly used. The aim of this work was to create conditions to advance the use of Saccharomyces cerevisiae laboratory strains for wine fermentation studies, considering previous results obtained for enological strains fermenting NGM under simulated winery conditions. We designed a new SGM formulation, ISA-SGM, by introducing specific modifications to a commonly used formulation, putting together previous reports. We added glucose and fructose in equal amounts (125 g/l) and 50 parts per million (ppm) sulfur dioxide (SO 2, corresponding to standard enological treatment), and we optimized the concentrations of malic acid (3 g/l), citric acid (0.3 g/l), and tartaric acid (3 g/l). Using ISA-SGM, we obtained similar fermentative profiles for the wine strain ISA1000, the prototrophic strain S288C, and its auxotrophic derivative BY4741. In this case, the concentrations of supplements were optimized to 120 mg/l L-uracil, 80 mg/l L-methionine, 400 mg/l L-leucine, and 100 mg/l L-histidine. All these strains tested in ISA-SGM presented a similar fermentative performance as ISA1000 in NGM. ISA-SGM formulation is a promising new tool to allow the use of the auxotrophic BY strains in the detailed assessment of the alcoholic fermentation process under simulated winery conditions, and it provides a foundation to extract relevant physiological conclusions in future research on enological yeast traits.

Research paper thumbnail of The high capacity specific fructose facilitator ZrFfz1 is essential for the fructophilic behavior of Zygosaccharomyces rouxii CBS 732T

Eukaryotic Cell, 2014

Zygosaccharomyces rouxii is a fructophilic yeast that consumes fructose preferably to glucose. Th... more Zygosaccharomyces rouxii is a fructophilic yeast that consumes fructose preferably to glucose. This behavior seems to be related to sugar uptake. In this study, we constructed Z. rouxii single-, double-, and triple-deletion mutants in the UL4 strain background (a ura3 strain derived from CBS 732 T ) by deleting the genes encoding the specific fructose facilitator Z. rouxii Ffz1 (ZrFfz1), the fructose/glucose facilitator ZrFfz2, and/or the fructose symporter ZrFsy1. We analyzed the effects on the growth phenotype, on kinetic parameters of fructose and glucose uptake, and on sugar consumption profiles. No growth phenotype was observed on fructose or glucose upon deletion of FFZ genes. Deletion of ZrFFZ1 drastically reduced fructose transport capacity, increased glucose transport capacity, and eliminated the fructophilic character, while deletion of ZrFFZ2 had almost no effect. The strain in which both FFZ genes were deleted presented even higher consumption of glucose than strain Zrffz1⌬, probably due to a reduced repressing effect of fructose. This study confirms the molecular basis of the Z. rouxii fructophilic character, demonstrating that ZrFfz1 is essential for Z. rouxii fructophilic behavior. The gene is a good candidate to improve the fructose fermentation performance of industrial Saccharomyces cerevisiae strains.

Research paper thumbnail of Exploring Three PIPs and Three TIPs of Grapevine for Transport of Water and Atypical Substrates through Heterologous Expression in aqy-null Yeast

PLoS ONE, 2014

Aquaporins are membrane channels that facilitate the transport of water and other small molecules... more Aquaporins are membrane channels that facilitate the transport of water and other small molecules across the cellular membranes. We examined the role of six aquaporins of Vitis vinifera (cv. Touriga nacional) in the transport of water and atypical substrates (other than water) in an aqy-null strain of Saccharomyces cerevisiae. Their functional characterization for water transport was performed by stopped-flow fluorescence spectroscopy. The evaluation of permeability coefficients (Pf) and activation energies (Ea) revealed that three aquaporins (VvTnPIP2;1, VvTnTIP1;1 and VvTnTIP2;2) are functional for water transport, while the other three (VvTnPIP1;4, VvTnPIP2;3 and VvTnTIP4;1) are non-functional. TIPs (VvTnTIP1;1 and VvTnTIP2;2) exhibited higher water permeability than VvTnPIP2;1. All functional aquaporins were found to be sensitive to HgCl2, since their water conductivity was reduced (24-38%) by the addition of 0.5 mM HgCl2. Expression of Vitis aquaporins caused different sensitive phenotypes to yeast strains when grown under hyperosmotic stress generated by KCl or sorbitol. Our results also indicate that Vitis aquaporins are putative transporters of other small molecules of physiological importance. Their sequence analyses revealed the presence of signature sequences for transport of ammonia, boron, CO2, H2O2 and urea. The phenotypic growth variations of yeast cells showed that heterologous expression of Vitis aquaporins increased susceptibility to externally applied boron and H2O2, suggesting the contribution of Vitis aquaporins in the transport of these species.