Search results for "Saccharomyce"
showing 10 items of 875 documents
Activation of the plant plasma membrane H+ -ATPase. Is there a direct interaction between lysophosphatidylcholine and the C-terminal part of the enzy…
1996
The antagonistic effects of the fungal toxin beticolin-1 and of L-alpha-lysophosphatidylcholine (lysoPC) were investigated on the plasma membrane H+-ATPase of the plant Arabidopsis thaliana (isoform 2) expressed in yeast, using both wild-type enzyme (AHA2) and C-terminal truncated enzyme (aha2delta92). Phosphohydrolytic activities of both enzymes were inhibited by beticolin-1, with very similar 50% inhibitory concentrations, indicating that the toxin action does not involve the C-terminal located autoinhibitory domain of the proton pump. Egg lysoPC, a compound that activates the H+-ATPase by a mechanism involving the C-terminal part of the protein, was found to be able to reverse the inhibi…
Development of a low-alcoholic fermented beverage employing cashew apple juice and non-conventional yeasts
2019
Cashew apples are by-products in the production of cashew nuts, which are mostly left to rot in the fields. Cashew apple juice (CAJ), a highly nutritious beverage, can be produced from them. It is rich in sugars and ascorbic acid, but its high polyphenol content makes it bitter and astringent, and therefore difficult to commercialize. The kingdom of fungi contains more than 2000 yeast species, of which only a few species have been studied in relation to their potential to produce aroma compounds. The aim of this research was to develop a new low-alcoholic fermented beverage to valorize cashew apples. For this purpose, a screening was carried out employing non-conventional yeast species and …
The roles of whole-genome and small-scale duplications in the functional specialization of Saccharomyces cerevisiae genes
2013
Researchers have long been enthralled with the idea that gene duplication can generate novel functions, crediting this process with great evolutionary importance. Empirical data shows that whole-genome duplications (WGDs) are more likely to be retained than small-scale duplications (SSDs), though their relative contribution to the functional fate of duplicates remains unexplored. Using the map of genetic interactions and the re-sequencing of 27 Saccharomyces cerevisiae genomes evolving for 2,200 generations we show that SSD-duplicates lead to neo-functionalization while WGD-duplicates partition ancestral functions. This conclusion is supported by: (a) SSD-duplicates establish more genetic i…
AtCCS is a functional homolog of the yeast copper chaperone Ccs1/Lys7
2005
AbstractIn plant chloroplasts two superoxide dismutase (SOD) activities occur, FeSOD and Cu/ZnSOD, with reciprocal regulation in response to copper availability. This system presents a unique model to study the regulation of metal-cofactor delivery to an organelle. The Arabidopsis thaliana gene AtCCS encodes a functional homolog to yeast Ccs1p/Lys7p, a copper chaperone for SOD. The AtCCS protein was localized to chloroplasts where it may supply copper to the stromal Cu/ZnSOD. AtCCS mRNA expression levels are upregulated in response to Cu-feeding and senescence. We propose that AtCCS expression is regulated to allow the most optimal use of Cu for photosynthesis.
Bioprospecting for brewers: Exploiting natural diversity for naturally diverse beers.
2019
The burgeoning interest in archaic, traditional, and novel beer styles has coincided with a growing appreciation of the role of yeasts in determining beer character as well as a better understanding of the ecology and biogeography of yeasts. Multiple studies in recent years have highlighted the potential of wild Saccharomyces and non‐Saccharomyces yeasts for production of beers with novel flavour profiles and other desirable properties. Yeasts isolated from spontaneously fermented beers as well as from other food systems (wine, bread, and kombucha) have shown promise for brewing application, and there is evidence that such cross‐system transfers have occurred naturally in the past. We revie…
Use of Kluyveromyces marxianus to Increase Free Monoterpenes and Aliphatic Esters in White Wines
2021
An increasing interest in novel wine productions is focused on non-Saccharomyces yeasts due to their potential in improving sensory profiles. Although Kluyveromyces marxianus has been originally isolated from grapes and its enzymatic activities are used in oenology, rarely it has been used as co-starter. The K. marxianus Km L2009 strain has been characterized here and selected as a co-starter both at laboratory- and winery-scale fermentation. The Km L2009 strain showed growth of up to 40 (mg/L) of sulfites and 6% (v/v) of ethanol. Gas chromatographic analysis demonstrates that wines produced by mixed fermentation contain remarkably higher quantities of free monoterpenes and aliphatic esters…
Anhydrobiosis in Yeasts: Changes in Mitochondrial Membranes Improve the Resistance of Saccharomyces cerevisiae Cells to Dehydration–Rehydration
2019
Anhydrobiosis is a unique state of live organisms in which their metabolism is temporary reversibly suspended as the result of strong dehydration of their cells. This state is widely used currently during large-capacity production of active dry baker&rsquo
Changes in Energy Status of Saccharomyces cerevisiae Cells During Dehydration and Rehydration
2021
Anhydrobiosis is the state of life when cells are exposed to waterless conditions and gradually cease their metabolism. In this study, we determined the sequence of events in Saccharomyces cerevisiae energy metabolism during processes of dehydration and rehydration. The intensities of respiration and acidification of the medium, the amounts of phenyldicarbaundecaborane (PCB−) bound to yeast membranes, and the capabilities of cells to accumulate K+ were assayed using an electrochemical monitoring system, and the intracellular content of ATP was measured using a bioluminescence assay. Mesophilic, semi-resistant to desiccation S. cerevisiae strain 14 and thermotolerant, very resistant to desic…
Involvement of osmotic cell shrinkage on the proton extrusion rate in Saccharomyces cerevisiae
2001
Saccharomyces cerevisiae has been subjected to hyperosmotic shocks by using permeating (sorbitol, xylitol, glycerol, NaCl) and nonpermeating (PEG 600) solutes. The proton extrusion rate decreased as the osmotic pressure increased, whichever solute was used. However, the total inhibition of the cellular H+ extrusion depended on the solute used. A total inhibition was observed at about 20 MPa with glycerol, xylitol and sorbitol. With PEG 600, a total inhibition of extracellular acidification was obtained at 8.5 MPa. NaCl, with an extracellular pressure of 37.8 MPa (near saturation), did not completely inhibit the extracellular acidification. These results showed that the total inhibition of p…
Kinetic studies on protoporphyrinogen oxidase inhibition by diphenyl ether herbicides
1991
Diphenyl ethers (DPEs) and related herbicides are powerful inhibitors of protoporphyrinogen oxidase, an enzyme involved in the biosynthesis of haems and chlorophylls. The inhibition kinetics of protoporphyrinogen oxidase of various origins by four DPEs, (methyl)-5-[2-chloro-4-(trifluoromethyl)phenoxy]-2-nitrobenzoic acid (acifluorfen and its methyl ester, acifluorfen-methyl), methyl-5-[2-chloro-4-(trifluoromethyl) phenoxy]-2-chlorobenzoate (LS 820340) and methyl-5-[2-chloro-5-(trifluoromethyl)phenoxy]-2-nitrobenzoic acid (RH 5348), were studied. The inhibitions of the enzymes from maize (Zea mays) mitochondrial and etiochloroplastic membranes and mouse liver mitochondrial membranes were com…