The ICY1 gene from Saccharomyces cerevisiae affects nitrogen consumption during alcoholic fermentation

Background: Saccharomyces cerevisiae is the main microorganism responsible for alcoholic fermentation. In this process, the consumption of nitrogen is of great importance since it is found in limiting quantities and its deficiency produces sluggish and/or stuck fermentations generating large economic losses in the wine-making industry. In a previous work we compared the transcriptional profiles between genetically related strains with differences in nitrogen consumption, detecting genes with differential expression that could be associated to the differences in the levels of nitrogen consumed. One of the genes identified was ICY1. With the aim of confirming this observation, in the present work we evaluated the consumption of ammonium during the fermentation of strains that have deleted or overexpressed this gene. Results: Our results confirm the effect of ICY1 on nitrogen uptake by evaluating its expression in wine yeasts during the first stages of fermentation under low (MS60) and normal (MS300) assimilable nitrogen. Our results show that the mRNA levels of ICY1 diminish when the amount of assimilable nitrogen is low. Furthermore, we constructed strains derived from the industrial strain EC1118 as a null mutant in this gene as well as one that overexpressed it. Conclusions: Our results suggest that the expression of ICY1 is regulated by theamount of nitrogen available in the must and it is involved in the consumption of ammonium, given the increase in the consumption of this nitrogen source observed in the null mutant strain

Identification of QTLs linked to fruit quality traits in apricot (Prunus armeniaca L.) and biological validation through gene expression analysis using qPCR

Nine important fruit quality traits\u2014including fruit weight, stone weight, fruit diameter, skin ground colour, flesh colour, blush colour, firmness, soluble solids content and acidity content\u2014were studied for two consecutive years in two F 1 apricot progeny derived from the crosses \u2018Bergeron\u2019 7 \u2018Currot\u2019 (B 7C) and \u2018Goldrich\u2019 7 \u2018Currot\u2019 (G 7C). Results showed great segregation variability between populations, which was expected because of the polygenic nature and quantitative inheritance of all the studied traits. In addition, some correlations were observed among the fruit quality traits studied. QTL (quantitative trait loci) analysis was carried out using the phenotypic data and genetic linkages maps of \u2018B 7C\u2019 and \u2018G 7C\u2019 obtained with SSR and SNP markers. The most significant QTLs were localised in LG4 for soluble solids content and in LG3 for skin and flesh colour. In LG4, we can highlight the presence of candidate genes involved in D-glucose and D-mannose binding, while in LG3, we identified MYB genes previously linked to skin colour by other authors. In order to clearly identify the candidate genes responsible for the analysed traits, we converted the QTLs into expression QTLs and analysed the abundance of transcripts in the segregating genotypes \u2018GC 2\u201311\u2019 and \u2018GC 3\u20137\u2019 from the G 7C population. Using qPCR, we analysed the gene expression of nine candidate genes associated with the QTLs identified, including transcription factors (MYB 10), carotenoid biosynthesis genes (LOX 2, CCD1 and CCD4), anthocyanin biosynthesis genes (ANS, UFGT and F3\u20195\u2019H), organic acid biosynthesis genes (NAD ME) and ripening date genes (NAC). Results showed variable expression patterns throughout fruit development and between contrasted genotypes, with a correlation between validated genes and linked QTLs. The MYB10 gene was the best candidate gene for skin colour. In addition, we found that monitoring NAC expression is a good RNA marker for evaluating ripening progression

Sim-to-real transfer and reality gap modeling in model predictive control for autonomous driving

The main challenge for the adoption of autonomous driving is to ensure an adequate level of safety. Considering the almost infinite variability of possible scenarios that autonomous vehicles would have to face, the use of autonomous driving simulators is becoming of utmost importance. Simulation suites allow the used of automated validation techniques in a wide variety of scenarios, and enable the development of closed-loop validation methods, such as machine learning and reinforcement learning approaches. However, simulation tools suffer from a standing flaw in that there is a noticeable gap between the simulation conditions and real-world scenarios. Although the use of simulators powers most of the research around autonomous driving, and is generally used within all domains it is divided into, there is an inherent source of error given the stochastic nature of activities performed in real world, which are unreplicable in computer environments. This paper proposes a new approach to assess the real-to-sim gap for path tracking systems. The aim is to narrow down the sources of error between simulation results and real-world conditions, and to evaluate the performance of the simulation suite in the design process by employing the information extracted from gap analysis, which adds a new dimension of development against other approaches for autonomous driving. A real-time model predictive controller (MPC) based on adaptive potential fields was developed and validated using the CARLA simulator. Both the path planning and vehicle control systems where tested in real traffic conditions. The error between the simulator and the real data acquisition was evaluated using the Pearson correlation coefficient (PCC) and the max normalized cross-correlation (MNCC). The controller was further evaluated on a process of sim-to-real transfer, and was finally tested both in simulation and real traffic conditions. A comparison was performed against an optimal-control ILQR-based model predictive controller was carried out to further showcase the validity of this approach

Cinnamic acid, ethanol and temperature interaction on coumarate decarboxylase activity and the relative expression of the putative cd gene in D. bruxellensis

Dekkera bruxellensis is one of the main contaminating yeasts in wine due to its ability to metabolize cinnamic acids into volatile phenols. This yeast metabolizes p-coumaric acid into 4-vinylphenol through a coumarate decarboxylase (CD) and then transforms it into to 4-ethylphenol (EF) through a vinylphenol reductase. In this work we investigated the influence of the interaction between the concentration of p-coumaric acid, ferulic acid and ethanol as well as growth temperature on the production of CD activity and the expression of a putative gene that codes for this enzymatic activity. For this, a Box Behnken experimental design was used. The concentration of p-coumaric acid (5-26 ppm) and ferulic acid (3-9 ppm) alone did not show any significant effect on any of the studied response variables. However, the interaction between (ethanol concentration * cinnamic acid concentration) and (ethanol concentration * temperature) had a significant statistical effect on the production of CD activity. Additionally, a higher growth temperature negatively affected the expression of the putative cd gene and the production of CD activity. This is the first work that studies the effect of cinnamic acids on the production of CD activity and the relative expression of its putative gene, using natural concentrations of cinnamic acid found in wine

Callus culture development of two varieties of Tagetes erecta and carotenoid production

Background: The properties of natural pigments, such as antioxidants, functional,medical, and nutraceutical, have demonstrated the advantages of these natural compounds over synthetic ones. Some products are accepted only when they are pigmented with natural, food-quality colorants: for example poultry products (manly marigold flower extracts). Carotenoids such as \u3b2-carotene, \u3b2-criptoxanthin and lutein are very attractive as natural food colorants due to their antioxidant and pro-vitamin activities which provide additional value to the target products. Marigold ( Tagetes erecta ) is an Asteraceous ornamental plant native to Mexico, and it is also important as a carotenoid source for industrial and medicinal purposes but nowadays its production is destined mainly for ornamental purposes. Results: Friable callus of T. erecta yellow flower (YF) and white flower (WF) varieties was induced from leaf explants on Murashige and Skoog (MS) medium supplemented with 9.0 \u3bcM 4-dichlorophenoxyacetic acid (2,4-D) and 8.8 \u3bcM benzyladenine (BA). Calluses developed from both varieties were different in pigmentation. Extract characterization from callus cultures was carried out by high-performance liquid chromatography (HPLC). This analytical process detected several carotenoids; the main pigments in extracts from YF callus were lutein and zeaxanthin, whereas in the extracts of the WF callus the main pigmentswere lutein, zeaxanthin, \u3b2-cryptoxanthin and \u3b2-carotene. Callus cultures of T. erecta accumulated pigments even after several rounds of subculture. Conclusions: WF callus appeared to be a suitable candidate as a source of different carotenoids, and tested varieties could represent an alternative for further studies about in vitro pigment production

Gene expression of specific enological traits in wine fermentation

Background: Wine fermentation is a dynamic process and yeast has a precise genic regulation system that allow them to coordinate the gene transcription levels. However, the fermentation stage at which there is a great variation in the genic expression associated to a particular enological trait is often unknown and there are no simple experimental approaches to define it. Results: To identify the most adequate stage in which to evaluate the expression of the genes associated to specific enological traits we identified three stages of fermentation using the industrial strain EC1118. These stages, called early (0-16.4 hrs), middle (16.4-88.7 hrs) and late (88.7 hrs onwards), were characterized according to changes in the speed of CO2 production. The greatest nitrogen consumption velocity (1.016 g/L h) was achieved in the early stage. The most significant changes in the consumption of sugar and ethanol production acceleration occurred in the middle stage, and the greatest velocity of ethanol production (0.043%/h) and fructose consumption (0.338 g/L h) occurred in the late stage. The expression profiles for a set of genes characteristic of these processes were clearly defined during the stages of fermentation: identifying a peak for the genes related to the consumption of nitrogen during the early stage, followed by an increase in the expression of genes related to the consumption of sugars in the middle stage. Finally, during the late stage there is a decrease in the expression of genes involved in the consumption of sugar, except for HXT3 the levels of which remain high. Conclusions: The kinetic and transcriptional profiles of the enological traits under study are clearly distinct and each is associated to a particular stage of the fermentation. Our results confirm that CO2 production is a simple parameter to estimate the stages of the fermentation. Therefore, using the kinetics of CO2 loss it is possible to select the most adequate moment to study the expression of genes associated to the main enological traits: sugar consumption and production of nitrogen and ethanol

Total RNA quality of lyophilized and cryopreserved dormant grapevine buds

Background: Plant tissues must be preserved in their collection state, especially for genome-wide expression profile studies. Lyophilization is a feasible, affordable tool when fresh tissues cannot be shipped at ultralow temperatures from their origin to the place of analysis. In this study, the total RNA quality of dormant grapevine buds ( Vitis vinifera L. cv. \u2018Flame Seedless\u2019) of freeze-dried samples stored at room temperature conditions was evaluated and compared to that of cryopreserved (-80\ub0C) grapevine buds. Results: Good yield and quality of RNA were obtained from freeze-dried dormant buds stored at room temperature for 0, 3 and 6 weeks after they were lyophilized. Further experiments confirmed that the extracted total RNA could be used for actin and \u3b2-tubulin PCR gene amplification. Conclusion: High-quality RNA that is useful for downstream applications was obtained from freeze-dried dormant grapevine bud tissue, similarly to the RNA obtained from cryopreserved dormant grapevine buds

Cytotoxic Acetogenins from the Roots of Annona purpurea

Annona purpurea, known in Mexico as "cabeza de negro" or "ilama", belongs to the Annonaceae family. Its roots are employed in folk medicine in several regions of Mexico. Taking that information into account, a chemical and biological analysis of the components present in the roots of this species was proposed. Our results demonstrated that the dichloromethane (DCM) extract was exclusively constituted by a mixture of five new acetogenins named annopurpuricins A-E (1-5). These compounds have an aliphatic chain of 37 carbons with a terminal \u3b1,\u3b2 unsaturated \u3b3-lactone. Compounds 1 and 2 belong to the adjacent bis-THF (tetrahydrofuran) \u3b1-monohydroxylated type, while compounds 3 and 4 belong to the adjacent bis-THF \u3b1,\u3b1'-dihydroxylated type; only compound 5 possesses a bis-epoxide system. Complete structure analysis was carried out by spectroscopy and chemical methods. All compounds were evaluated for their antiproliferative activity on three human tumor cell lines (MSTO-211H, HeLa and HepG2). Compounds 1-4 inhibited significantly the growth of HeLa and HepG2 cells, showing GI50 values in the low/subnanomolar range, while 5 was completely ineffective under the tested conditions. The investigation of the mechanism of action responsible for cytotoxicity revealed for the most interesting compound 1 the ability to block the complex I activity on isolated rat liver mitochondria (RLM)

Modification of the activity of an \u3b1-amylase from Bacillus licheniformis by several surfactants

The influence of different commercial surfactants on the enzymatic activity of a commercial \u3b1-amylase from Bacillus licheniformis (Termamyl 300 L) has been studied. As non-ionic surfactants, alkyl polyglycosides (Glucopon\uae 215, Glucopon\uae 600 and Glucopon\uae 650) were studied, as were fatty alcohol ethoxylates (Findet 1214N/23 and Findet 10/15), and nonyl phenol ethoxylate (Findet 9Q/21.5NF). Also, an anionic surfactant, linear alkyl benzene sulfonate (LAS) was assayed. In general, none of the non-ionic surfactants studied, except Findet 10/15, vary substantially the enzymatic activity. Findet 10/15 has the strongest hydrophobic character and reduces the enzymatic activity more significantly the greater its concentration. Regarding LAS, this surfactant significantly depressed enzymatic activity, presumably due to the electrostatic interactions caused by its anionic character

Ionize Hard: Interstellar PO+ Detection

We report the first detection of the phosphorus monoxide ion (PO+) in the interstellar medium. Our unbiased and very sensitive spectral survey toward the G+0.693–0.027 molecular cloud covers four different rotational transitions of this molecule, two of which (J = 1–0 and J = 2–1) appear free of contamination from other species. The fit performed, assuming local thermodynamic equilibrium conditions, yields a column density of N=(6.0 \ub1 0.7) 7 1011\ua0cm−2. The resulting molecular abundance with respect to molecular hydrogen is 4.5 7 10–12. The column density of PO+ normalized by the cosmic abundance of P is larger than those of NO+ and SO+, normalized by N and S, by factors of 3.6 and 2.3, respectively. The N(PO+)/N(PO) ratio is 0.12 \ub1 0.03, more than one order of magnitude higher than that of N(SO+)/N(SO) and N(NO+)/N(NO). These results indicate that P is more efficiently ionized than N and S in the ISM. We have performed new chemical models that confirm that the PO+ abundance is strongly enhanced in shocked regions with high values of cosmic-ray ionization rates (10–15 − 10–14 s−1), as occurring in the G+0.693–0.027 molecular cloud. The shocks sputter the interstellar icy grain mantles, releasing into the gas phase most of their P content, mainly in the form of PH3, which is converted into atomic P, and then ionized efficiently by cosmic rays, forming P+. Further reactions with O2 and OH produces PO+. The cosmic-ray ionization of PO might also contribute significantly, which would explain the high N(PO+)/N(PO) ratio observed. The relatively high gas-phase abundance of PO+ with respect to other P-bearing species stresses the relevance of this species in the interstellar chemistry of P