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Surface matters: Decarburising wootz crucible steel ingots
No full textWootz, the Indian crucible steel, is a hypereutectoid iron–carbon alloy and famous for its outstanding qualities. Due to the paucity of archaeological and historical ingot finds and conservative sampling strategies, discussions of the homogeneity of such ingots and the microstructural representativeness of samples have remained generic and assumptive. Thus two major shortcomings in the study of crucible steel ingots include the determination of their absolute carbon content and its relative distribution across the ingots. The recent discovery of a large hoard of wootz ingots from Telangana (Jaikishan et al. 2021) offered a unique opportunity to study their microstructure and determine their carbon content.
Reports based on traditional metallography suggest a wide carbon range, from 1 to 2 wt% carbon, for similar ingots (Scott 2013). Recent work based on image analysis (Desai and Rehren 2023) offered narrower carbon estimates (about 1.8 wt%) for several of the recently discovered ingots, with some variation in concentration towards the edge of the samples. As a collaborative effort to determine absolute carbon values and potential uneven distribution of the carbon in the Telangana ingots, traditional metallography was coupled with laser-induced breakdown spectroscopy (LIBS). Beyond documenting the microstructure across several ingots, the study provides macrostructural evidence of rim decarburisation, which we believe to be intentional. This study presents the micro- and macrostructure of two of the hypereutectoid Telangana ingots, highlighting the skill of the craftsmen in decarburising the outer surfaces of their ingots, potentially for ease of subsequent forging.We are grateful for the state authorities of Telangana for permission to study the ingots. We warmly acknowledge the previous scholarship for the tremendous efforts in generating knowledge on crucible steel production in Telangana and elsewhere. Comments from three anonymous reviewers are gratefully acknowledged and have helped to strengthen the paper; all remaining errors are ours. This is a publication from the A. G. Leventis Chair in Archaeological Sciences at the Cyprus Institute; the support from the A. G. Leventis Foundation is gratefully acknowledged. We submit our warm thanks to the Gerda Henkel Foundation for funding the PhD study of the first author. This project received funding from the European Union's Horizon 2020 research and innovation programme for the PROMISED project, under grant agreement 811068, which facilitated Marc Gener's travel to and work at the Cyprus Institute. The authors declare no competing interests.Peer reviewe
Bacteriophages carry auxiliary metabolic genes related to energy, sulfur and phosphorus metabolism during a harmful algal bloom in a freshwater lake
No full text11 pages, 10 figures, supplementary data https://doi.org/10.1016/j.chemosphere.2024.143819.-- Data availability: Data will be made available on request: Bhattarai, Bishav; Shankar Bhattacharjee, Ananda; Coutinho, Felipe Hernandes; Li, Hanyan; Chadalavada, Sreeni; Goel, Ramesh K.; 2023; Study of cyanobacteria and bacterioplankton during different stages of a cyanobacterial bloom in Utah Lake [Dataset]; National Center for Biotechnology Information; https://www.ncbi.nlm.nih.gov/bioproject/PRJNA876583/Cyanophages play an important role in nutrient cycling in lakes since they can modulate the metabolism of cyanobacteria. A proper understanding of the impact of cyanophage infection on the metabolism and ecology of cyanobacteria is critical during a complete cycle of harmful algal bloom (HAB). The ecology of cyanophages in marine environments has been well-delineated, but cyanophages in freshwater lakes remain less studied. Here, we studied the diversity of cyanophages and their impact on host ecology and metabolism through the succession of HAB in Utah Lake, which is a shallow eutrophic freshwater lake, in 2019. We collected water samples at three different periods from two locations in freshwater Utah Lake. The three sampling periods represented the pre-bloom, peak-bloom, and post-bloom events. We observed that the Utah Lake virome was dominated by families Myoviridae, Siphoviridae, and Podoviridae under the order Caudovirales. We detected photosystem-related genes, sulfur assimilation genes, and pho regulon (phosphorus metabolism) genes in genomes of predicted cyanophages. We were able to capture the changes in relative abundance and expression of functional genes in genomes of cyanophage at different stages of the bloom. We observed higher relative abundance and expression of cyanophage-encoded pho-regulon genes in the “pre-bloom” period. The higher expression of pho-regulon genes in P-limited ecosystem of Utah Lake indicated the possible contribution of cyanophage to enhance the fitness of the host cyanobacteria. Our study provides some insightful findings on the role of cyanophages in controlling the ecology and relative abundance of host cyanobacteria in freshwater lakesThis study was conducted under research Grant # 2222322 awarded to Dr. RG by the United States National Science FoundationWith the institutional support of the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S)Peer reviewe
DNA microgels obtained by coacervation with gelatin in the presence of a polysaccharide
No full textPeer reviewe
Advanced LC-IMS-MS Protocol for Holistic Metabolite Analysis in Wine and Grape Samples
No full textThe final aim of metabolomics is the comprehensive and holistic study of the metabolome in biological samples. Therefore, the use of instruments that enable the analysis of metabolites belonging to various chemical classes in a wide range of concentrations is essential, without compromising on robustness, resolution, sensitivity, specificity, and metabolite annotation. These characteristics are crucial for the analysis of very complex samples, such as wine, whose metabolome is the result of the sum of metabolites derived from grapes, yeast(s), bacteria(s), and chemical or physical modification during winemaking. In recent years, a big advantage, in this direction, was the hardware developments on hyphenated instruments that enable the integration of liquid chromatography (LC), ion mobility spectrometry (IMS), and mass spectrometry (MS). This chapter describes an LC-IMS-MS protocol for the analysis of wine and grape samples as well as the use of IMS data in metabolite annotation.The research was funded by the ERDF 2014–2020 Program of the Autonomous Province of Trento (Italy) with EU co-financing (Fruitomics).Peer reviewe
Coordinates of sampling sites in aquatic environments of Madrid County (2017-2022) [in Spanish]
No full textThis dataset encompasses data on freshwater sites sampled for environmental data and algae in Madrid County in the 2017-2022 period.Madrid Sampling Sites (2017-2022).txtPeer reviewe
Comparative analysis of transcriptomic responses in wine yeast cells triggered by yeast extracellular vesicles or whole cells
No full textTrabajo presentado en el 10th Congress of European Microbiologists (FEMS 2023), celebrado en Hamburgo (Alemania), del 9 al 13 de julio de 2023Background: The use of non-Saccharomyces yeast species in the wine industry has been increasing in
recent years. These alterna¿ve yeasts are o¿¿en used in conjunc¿¿on with Saccharomyces cerevisiae to
ensure complete fermenta¿¿on. However, this can lead to poten¿¿al interac¿¿ons between the different
yeast species, which can impact the outcome of wine fermenta¿¿on. Our previous research has
demonstrated that when S. cerevisiae comes into contact with other wine yeast species, there are
transcrip¿¿onal responses with both common and species-specific features (Curiel et al., 2017).
Objec¿¿ves: In this study, we test the hypothesis that extracellular vesicles (EVs) play a role in the
biological interac¿¿ons.
Methods: S. cerevisiae cultures were exposed to purified EVs from Metschnikowia pulcherrima. We
then evaluated the impact of these EVs on the physiology of S. cerevisiae using transcriptomic analysis
and compared the results to the response of S. cerevisiae to whole M. pulcherrima cells under the
same experimental condi¿ons.
Results: Our analysis reveals an important overlap in the transcrip¿¿onal responses in S. cerevisiae
induced by either M. pulcherrima cells or EVs. Both appear to induce transcrip¿¿on of genes related to
glycolysis and ribosomal ac¿¿vity and repress vacuolar transport. These results confirm that S. cerevisiae
directly responds to compe¿¿ng species under wine-like condi¿¿ons and provide the first experimental
support for the hypothesis that recogni¿¿on mechanisms involve, at least in part, EVs. Based on these
findings, we proceeded to evaluate the reac¿¿on of S. cerevisiae against EVs from other yeast species of
oenological interest
Hydrogen Sulfide-Induced Barley Resilience to Drought and Salinity through Protein Persulfidation
No full textChemicals and CAS Registry Numbers
hydrogen sulfide 15035-72-0, 7783-06-4
sulfide 18496-25-8
Hydrogen Sulfide
Plant Proteins
Reactive Oxygen Species
sodium bisulfide
SulfidesBarley (Hordeum vulgare) is a widely cultivated cereal crops, and its production is increasingly threatened by environmental stresses such as drought and salinity. Hydrogen sulfide is established as a signaling molecule that promotes tolerance to plant stress throught persulfidation, a post-translational modification of cysteine residues in proteins. The purpose of this study is to explore the impact of NaHS (sulfide donor) pretreatment on barley plants in enhancing tolerance to drought and salinity stresses, and determine if persulfidation is involved. In pretreated-plants, phenotypical traits and pigment contents showed an improvement in the survival of the plants under stress conditions. Quantification of stress-markers such as anthocyanin, proline, and reactive oxygen species also showed significant decreased contents in pretreated compared to untreated plants. In addition, the accumulation of amino acids under drought stress was significantly reduced when plants were pretreated with NaHS. Similarly, the increase of ABA content as a typical drought response was reduced in the pretreated plants. When plants are exposed to salt stress, the Na+/K+ ratio was maintained low in NaHS-pretreated plants, by increasing K+ levels. The sulfide ameliorative effect to salt was also observed during germination in previously NaHS-soaked seeds. Our findings suggest that sulfide pretreatment prepares barely plants to better deal with drought and salinity. Moreover, persulfidation was analyzed under all conditions, exhibiting enhanced levels under stress when plants were pretreated with NaHS. Our findings indicate that sulfide pretreatment induces a previous state in barley to respond more efficiently to stress and propose persulfidation is the underlying mechanism.This work was supported by Junta de Andalucia (grant No. P18-RT-3154) and ERDF A way of making Europe and MCIN/AEI/10.13039/501100011033 and NextGenerationEU/PRTR (grant No. TED2021-131443B-I00 and PID2022-141885NB-I00). Reyes Carrillo was supported by AEI through the predoctoral contract PREP2022-000606. We thank Dr. González-Andrés, Institute of Environmental, Natural Resources and Biodiversity, University of León, Spain, for providing the barley seeds.Peer reviewe
A single route for the production of battery-type and capacitor-type electrode materials
No full textThe quest for green and effective synthetic routes towards energy grade materials is of utmost relevance in the transition to a fossil-free energy model. In a previous work we have shown the promising role of harmless MgSO4 in the synthesis of S-doped carbon anodes for fast sodium storage. Herein, we show that the same simple procedure can be used for the production of high surface, supercapacitor-type materials, by merely changing the temperature of the thermal treatment. We also found that the addition of an inert salt such as KCl -in small amounts- greatly boosts the porogenic activity of MgSO4, leading to carbons with SBET above 2000 m2 g−1. As a proof of concept, and using biomass-based substances as carbon precursors, we have built a hybrid sodium-ion capacitor out of a S-doped carbon and a highly porous carbon, both of them prepared using similar MgSO4-assisted synthetic schemes. The full cell built with similar positive and negative electrode masses exhibited a good energy/power performance (38Wh kg−1 at 22 kW kg−1), as well as a very robust cycling stability, with a capacity fade of only 0.00078 % cycle−1.This research work was supported by project IDI/2018/000148 (FICYT/FEDER) and PID2021-123648OB-I00 (MCIN/AEI/10.13039/501100011033/and ERDF A way of making Europe). S. Payá also thanks the Principality of Asturias for her Yo Investigo contract.Peer reviewe
Predictive evolution of metabolic phenotypes using model-designed environments
Get PDFTrabajo presentado en el SIMB Annual meeting 2023 (Society for Industrial Microbiology and Biotechnology), celebrado en Minneapolis (Estados Unidos), del 30 de julio al 2 de agosto de 2023Adaptive evolution under controlled laboratory conditions has been highly effective in selecting organisms with beneficial phenotypes such as stress tolerance. The evolution route is particularly attractive when the organisms are either difficult to engineer or the genetic basis of the phenotype is complex. However, many desired traits, like metabolite secretion, have been inaccessible to adaptive selection due to their trade-off with cell growth. Here, we utilize genome-scale metabolic models to design nutrient environments for selecting lineages with enhanced metabolite secretion. To overcome the growth-secretion trade-off, we identify environments wherein growth becomes correlated with a secondary trait termed tacking trait. The latter is selected to be coupled with the desired trait in the application environment where the trait manifestation is required. Thus, adaptive evolution in the model-designed selection environment and subsequent return to the application environment is predicted to enhance the desired trait. We experimentally validate this strategy by evolving Saccharomyces cerevisiae for increased secretion of aroma compounds, and confirm the predicted flux-rerouting using genomic, transcriptomic, and proteomic analyses. Overall, model-designed selection environments open new opportunities for predictive evolution
Modulation of the KEAP1–NRF2 Pathway for the Treatment of Neurodegenerative Diseases: Rationale, Assay Methodologies, and Reference Compounds
No full textThe KEAP1–NRF2–ARE pathway is the master regulator of antioxidant and cytoprotective responses to oxidative and electrophilic stress. The KEAP1–NRF2 interaction can be disrupted by direct interference with the protein–protein interface or by covalent modification of cysteine residues at the “sensor” region of KEAP1. A number of biophysical methods are useful to characterize the KEAP1–NRF2 protein–protein interaction, including fluorescence polarization, fluorescence correlation spectroscopy, Förster resonance energy transfer, thermal shift assay, isothermal titration calorimetry, surface plasmon resonance, biolayer interferometry, analytical ultracentrifugation, electrophoretic mobility shift assay, circular dichroism, saturation transfer difference NMR experiments, and X-ray crystallography. On the other hand, considering that NRF2 is a master regulator of many cytoprotective genes and represents a cross talk of numerous key signaling pathways, the biological evaluation of potential NRF2 activators generally comprises their ability to promote NRF2 activation and translocation to the nucleus and also the levels of expression of NRF2-controlled proteins and the mechanism by which NRF2 is activated. A number of biological techniques are employed for this purpose, including immunocytochemistry and immunohistochemistry, the study of gene reporter cell lines, and the activation and expression of key genes and proteins, as well as the use of knockdown/knockout cell and animal models. Regarding mechanistic studies, covalent bonding to KEAP1 can be established by KEAP1 isolation through immunoprecipitation followed by mass spectrometry or HPLC/UPLC. FRET-based techniques and the proximity ligation assay allow to assess whether the KEAP1–NRF2 interaction is disrupted by a particular compound.We gratefully acknowledge financial support from MICINU
(grants PID2021-124983OB-I00 and PID2021-123481OB-
I00), Comunidad de Madrid (grant P2022/BMD-7230-CAM-
22), Instituto de Salud Carlos III (grant PI20/00433), and
European COST Action CA20121: Bench to bedside transition
for pharmacological regulation of NRF2 in noncommunicable dis-
eases (BenBedPhar)Peer reviewe