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Diseases caused by a compromised immune system, characterized by decreased production and diversification of T lymphocytes, such as immunodeficiencies or chronic infections, are becoming increasingly prominent. These diseases lead to increased vulnerability to infections caused by parasites, viruses, bacteria, fungi, and other microorganisms. According to various articles, Trametes versicolor has been used as immunotherapy and cancer treatment due to its polysaccharides, which have shown their value in traditional medicine. However, most of the studies have been done with Asian samples. For this reason, the aim of this study was to evaluate the effect of samples of Mexican T. versicolor on human lymphoid cells. Of various extracts, the one with the best T cell proliferative response was the extract produced by maceration in water at room temperature, but all treatments in aqueous and ethanolic extracts increased the lymphocyte count, showing that extracts of Mexican T. versicolor also have compounds that stimulate T cells. Unfortunately, genetic damage expressed as an increment in micronuclei count was identified, so using these fungus extracts in traditional medicine would require careful control of recommended doses.

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There are many factors involved in the incidence of Alzheimer's disease that, in combination, impede or hinder normal neuronal functions. Little is currently known about calcium regulation before and during the disease. Internal instability of calcium levels is associated with increased vascular risk, a prevalent condition in a high number of individuals already compromised by Alzheimer's disease. This review provides a reevaluation of the molecular mechanism of the sarcoendoplasmic reticulum calcium ATPase (SERC-A) in the disease and discusses salient aspects of voltage-gated calcium channel function; in these way new alternatives could be open for its treatment. These regulation mechanisms are clinically relevant since the irregular functions of SERC+A has been implicated in pathologies of brain function.

Hay muchos factores implicados en la incidencia de la enfermedad de Alzheimer que, en combinación, terminan por impedir o dificultar las funciones neuronales normales. Actualmente, poco se conoce sobre la regulación del calcio, antes de la enfermedad y durante la misma. La inestabilidad interna de los niveles de calcio se asocia a un mayor riesgo vascular, condición prevalente en un gran número de individuos ya comprometidos por la enfermedad de Alzheimer. Esta revisión proporciona una reevaluación de los mecanismos moleculares de la ATPasa dependiente de Ca2+ del retículo sarcoendoplásmico (SERC-A) en la enfermedad y analiza los aspectos más destacados de la función de los canales de calcio dependientes de voltaje; de esta manera, se podrán abrir nuevas alternativas de tratamiento. Estos mecanismos de regulación son clínicamente relevantes, ya que se ha implicado la función irregular de SERC-A en diversas alteraciones de la función cerebral.

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Hay muchos factores implicados en la incidencia de la enfermedad de Alzheimer que, en combinación, terminan por impedir o dificultar las funciones neuronales normales. Actualmente, poco se conoce sobre la regulación del calcio, antes de la enfermedad y durante la misma. La inestabilidad interna de los niveles de calcio se asocia a un mayor riesgo vascular, condición prevalente en un gran número de individuos ya comprometidos por la enfermedad de Alzheimer. Esta revisión proporciona una reevaluación de los mecanismos moleculares de la ATPasa dependiente de Ca2+ del retículo sarcoendoplásmico (SERC-A) en la enfermedad y analiza los aspectos más destacados de la función de los canales de calcio dependientes de voltaje; de esta manera, se podrán abrir nuevas alternativas de tratamiento. Estos mecanismos de regulación son clínicamente relevantes, ya que se ha implicado la función irregular de SERC-A en diversas alteraciones de la función cerebral.

There are many factors involved in the incidence of Alzheimer's disease that, in combination, impede or hinder normal neuronal functions. Little is currently known about calcium regulation before and during the disease. Internal instability of calcium levels is associated with increased vascular risk, a prevalent condition in a high number of individuals already compromised by Alzheimer's disease. This review provides a reevaluation of the molecular mechanism of the sarcoendoplasmic reticulum calcium ATPase (SERC-A) in the disease and discusses salient aspects of voltage-gated calcium channel function; in these way new alternatives could be open for its treatment. These regulation mechanisms are clinically relevant since the irregular functions of SERC+A has been implicated in pathologies of brain function.

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Eisosomes are nanoscale plasma membrane domains shaped as furrow-like invaginations. InSaccharomyces cerevisiaethese relatively immobile and uniform structures are mainly composed of two cytoplasmic proteins Pil1 and Lsp1. The present work uses fluctuation of fluorescence signals and analytical methods to determine Pil1 and Lsp1 dynamics at different subcellular locations. Using scanning techniques and autocorrelation analysis we determine that the cytoplasmic pools of Pil1 and Lsp1 behave mainly by passive diffusion. Single-point FCS experiments performed at several subcellular locations reveal that Pil1 mobility is faster in daughter cells. Furthermore, pair correlation function analysis indicates a rapid dynamic of Pil1 near the plasma membrane of growing yeast buds, where the membrane is expected to be actively assembling eisosomes.

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Background: There are widespread concerns that the COVID-19 pandemic may increase suicides. Few studies have analysed effects beyond the pandemic's early months or examined changes in known suicide risk factors. Methods: Using time series models fit with Poisson regression, we analysed monthly police-reported suicides in Ecuador from January 2015 to June 2021. Treating March 2020 as the start of the pandemic, we calculated rate ratios (RRs) comparing the observed to the expected number of suicides for the total population and by age and sex groups. We investigated changes in risk factors, precipitants, geographic distribution, and suicide methods. Findings: There was no evidence that suicide rates were higher than expected during the pandemic (RR 0·97 [95% CI 0·92-1·02]). There was some evidence of fewer than expected male suicides (RR 0·95 [95% CI 0·90-1·00]). The proportion of suicides occurring in urban and coastal areas increased but decreased amongst indigenous and other minorities. The proportions of suicides with evidence of alcohol consumption, disability, and amongst married and cohabiting individuals decreased, whereas suicides where mental health problems were considered contributory increased. There were relative increases in the proportion of suicides by hanging but decreases in self-poisoning and other suicide methods. Interpretation: The pandemic did not appear to adversely impact overall suicide numbers nationwide during the first 16 months of the pandemic. Reduced alcohol consumption may have contributed to the decline in male suicides. Funding: None.

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Sexual reproduction consists of genome reduction by meiosis and subsequent gamete fusion. The presence of genes homologous to eukaryotic meiotic genes in archaea and bacteria suggests that DNA repair mechanisms evolved towards meiotic recombination. However, fusogenic proteins resembling those found in gamete fusion in eukaryotes have so far not been found in prokaryotes. Here, we identify archaeal proteins that are homologs of fusexins, a superfamily of fusogens that mediate eukaryotic gamete and somatic cell fusion, as well as virus entry. The crystal structure of a trimeric archaeal fusexin (Fusexin1 or Fsx1) reveals an archetypical fusexin architecture with unique features such as a six-helix bundle and an additional globular domain. Ectopically expressed Fusexin1 can fuse mammalian cells, and this process involves the additional globular domain and a conserved fusion loop. Furthermore, archaeal fusexin genes are found within integrated mobile elements, suggesting potential roles in cell-cell fusion and gene exchange in archaea, as well as different scenarios for the evolutionary history of fusexins.

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ETHNOPHARMACOLOGICAL RELEVANCE: Although Mexican oregano inhibits digestive enzymes in vitro its effect on the absorption of carbohydrates and lipids in vivo has not been addressed. AIM OF THE STUDY: Assess the effect of Mexican oregano (Lippia graveolens Kunth) on carbohydrates and lipids absorption in vivo. The antioxidant activity also was investigated. MATERIALS AND METHODS: Enzymatic inhibitory action of lipase, α-amylase, and α-glucosidase was evaluated in vitro. Oral lipid (OLTT) and starch tolerance tests (OSTT) were conducted with L. graveolens acetone (O-A) and ethanol (O-E) extracts (at 102 mg/kg body weight equivalent to a 1 g human doses) in male Wistar rats. The antioxidant activity was evaluated through inhibition of lipid peroxidation and scavenging radical. RESULTS: Both extracts exhibited higher inhibitory median concentration (IC50) of lipase activity (1.9 µg/µL for O-E and 1.8 µg/µL for O-A) than the positive control (Orlistat) (0.07 µg/µL). The IC50 of α-amylase was higher (41.8 µg/µL for O-E and 25.2 µg/µL for O-A) than the Acarbose (2.5 µg/µL); while α-glucosidase results showed not statistically differences between groups (∼1.7 µg/µL). The OLTT results showed that both extracts significantly reduced serum triglycerides (∼147 mg/dL for O-E and ∼155 mg/dL for O-A) as compared with negative control group (only lipid load). In the OSTT, glucose levels showed a significant decrease (∼31 mg/dL for O-E and ∼17 mg/dL for O-A) than the negative control group (only starch load). About in vitro antioxidant evaluation, not statistically differences between extracts and positive control (Trolox) were observed for scavenged free radicals (∼2.0 µg/µL); whereas O-A inhibited lipid peroxidation similar to the Trolox (∼0.8 µg/µL IC50). The main chemical composition of both extracts was coumaric acid, luteolin, rutinoside, naringenin, and carvacrol. CONCLUSIONS: Both extracts reduce lipid absorption; whereas O-E decreases carbohydrate absorption in vivo. Both extracts inhibit lipid peroxidation and scavenging free radicals in vitro.

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Calcium (Ca2+) is a universal second messenger that participates in the regulation of innumerous physiological processes. The way in which local elevations of the cytosolic Ca2+ concentration spread in space and time is key for the versatility of the signals. Ca2+ diffusion in the cytosol is hindered by its interaction with proteins that act as buffers. Depending on the concentrations and the kinetics of the interactions, there is a large range of values at which Ca2+ diffusion can proceed. Having reliable estimates of this range, particularly of its highest end, which corresponds to the ions free diffusion, is key to understand how the signals propagate. In this work, we present the first experimental results with which the Ca2+-free diffusion coefficient is directly quantified in the cytosol of living cells. By means of fluorescence correlation spectroscopy experiments performed in Xenopus laevis oocytes and in cells of Saccharomyces cerevisiae, we show that the ions can freely diffuse in the cytosol at a higher rate than previously thought.

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The agaves are plants of cultural importance which have been used by humans for about 10,000 years and about 40 specific uses. The most culturally and economically important of those uses are for the production of fermented (pulque) and distilled beverages (mescal). Pulque continues to be produced in nearly all of Mexico, and the agaves used for this purpose have shown domestication syndrome. We carry out an ethnobotanical, morphological, and genetic analysis of the traditional varieties of pulque agave used in the production of aguamiel (agave sap) and pulque in the state of Hidalgo. We did semi-structured interviews, free listings, and tours with 11 agave managers. We analyzed morphology and studied genetic diversity and structure using nuclear microsatellites. We found wild-collected, tolerated, transplanted, and cultivated varieties of agave. This comprised 19 traditional varieties of pulque agave, 12 of them in production during the study, which corresponded to the species Agave americana, A. salmiana y A. mapisaga and five intraspecific entities. The varieties were grouped morphologically according to a management gradient; the wild-collected varieties were the smallest, with more lateral teeth and a larger terminal spine. The cultivated varieties clearly exhibited domestication syndrome, with larger plants and smaller dentition. The expected heterozygosity (He) of the varieties ranged from 0.204 to 0.721. Bayesian clustering suggested the existence of three genetic groups, both at the level of traditional varieties of pulque agaves and for management categories, a result that matches multivariate clustering. Pulque producers in the studied localities maintain high agrobiodiversity. The cultivated varieties exhibit domestication syndrome, as has been reported for other species of the genus with the same selection purposes. Our results support the hypothesis of a decrease in genetic diversity in crops compared to wild-growing agaves, which seems to be due to vegetative propagation, among other factors.

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Los protocolos ERAS por sus siglas en inglés (Enhanced Recovery after Surgery) se centran en reducir las complicaciones postoperatorias y la respuesta al estrés, optimizando la recuperación postoperatoria, dentro de las intervenciones el inicio temprano de la alimentación ha demostrado ser eficaz para reducir la morbilidad, los costos generales y la satisfacción del paciente. El presente estudio, revisión bibliográfica, plantea la importancia de tomar este tipo de medidas en pacientes con derivación biliodigestiva en el Hospital Médico Quirúrgico del Instituto Salvadoreños del Seguro Social. Cuantificar este aspecto en el Hospital Médico Quirúrgico del ISSS permitirá profundizar en estudios clínicos o analíticos para posteriormente implementar y protocolizar la intervención

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Fifty-five adult Dicrocoelium rileyi Macy, 1931 parasitizing Tadarida brasiliensis (Geoffroy, 1824) from Durango, Nuevo Leon, Puebla, Zacatecas and Mexico State were morphologically described and morphometrically analyzed. To evaluate the degree of variation among populations from the five localities, 27 morphometric measures of this species were transformed into an orthogonal factor by principal component analysis (PCA), and a posterior comparison among populations was performed using discriminant analysis of principal components (DAPC). Significant differences were observed with exceptions between the Puebla - Zacatecas and Nuevo Leon - Mexico State populations when forming three groups with an 88 % assignation. The Durango population was the most dissimilar population. These results show that the morphological traits of D. rileyi are variable among the populations in this study due to local intraspecific variation; however, some of the specimens present in the distinct localities may represent different species. Molecular analysis is necessary to accurately define whether the populations involved in our study constitute one or several species.

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Resumen La pancreatitis aguda es un trastorno intracelular del calcio en las células pancreáticas, el cual constituye la vía final común de múltiples estímulos etiopatogénicos y puede desencadenar cambios necroinflamatorios locales, efectos multisistémicos y compromiso en órganos distantes. Todo esto lleva a los pacientes a múltiples complicaciones por disfunción orgánica e infección. El diagnóstico adecuado y oportuno, el abordaje según severidad y la optimización de la terapia nutricional, así como una adecuada analgésica, reanimación hídroelectrolítica, detección de disfunción orgánica y de complicaciones locales e infecciosas, determinan el desenlace clínico de dicha patología. Se realizó una revisión narrativa incluyendo estudios clínicos, guías de manejo, protocolos y revisiones pertinentes, y se aporta un enfoque desde el punto de vista de medicina crítica para el abordaje inicial de esta patología.

Abstract Acute pancreatitis is an intracellular calcium disorder in pancreatic cells, which constitutes the final common pathway of multiple etiopathogenic stimuli and can trigger local necroinflammatory changes, multisystemic effects and compromise distant organs. All of this leads to multiple complications due to organ dysfunction and infection in patients. The adequate and opportune diagnosis, the approach according to severity and the optimization of the nutritional therapy; as well as an adequate analgesic, hydroelectrolytic resuscitation, the detection of organic dysfunction and of local and infectious complications, determine the clinical outcome of this pathology. A narrative review was carried out including clinical studies, management guidelines, protocols and reviews. An initial approach for this pathology, from the critical medicine point of view, is provided.

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Hanseniaspora is the main genus of the apiculate yeast group that represents approximately 70% of the grape-associated microflora. Hanseniaspora vineae is emerging as a promising species for quality wine production compared to other non-Saccharomyces species. Wines produced by H. vineae with Saccharomyces cerevisiae consistently exhibit more intense fruity flavors and complexity than wines produced by S. cerevisiae alone. In this work, genome sequencing, assembling, and phylogenetic analysis of two strains of H. vineae showed that it is a member of the Saccharomyces complex and it diverged before the whole-genome duplication (WGD) event from this clade. Specific flavor gene duplications and absences were identified in the H. vineae genome compared to 14 fully sequenced industrial S. cerevisiae genomes. The increased formation of 2-phenylethyl acetate and phenylpropanoids such as 2-phenylethyl and benzyl alcohols might be explained by gene duplications of H. vineae aromatic amino acid aminotransferases (ARO8 and ARO9) and phenylpyruvate decarboxylases (ARO10). Transcriptome and aroma profiles under fermentation conditions confirmed these genes were highly expressed at the beginning of stationary phase coupled to the production of their related compounds. The extremely high level of acetate esters produced by H. vineae compared to that by S. cerevisiae is consistent with the identification of six novel proteins with alcohol acetyltransferase (AATase) domains. The absence of the branched-chain amino acid transaminases (BAT2) and acyl coenzyme A (acyl-CoA)/ethanol O-acyltransferases (EEB1) genes correlates with H. vineae's reduced production of branched-chain higher alcohols, fatty acids, and ethyl esters, respectively. Our study provides sustenance for understanding and potentially utilizing genes that determine fermentation aromas.IMPORTANCE The huge diversity of non-Saccharomyces yeasts in grapes is dominated by the apiculate genus Hanseniaspora Two native strains of Hanseniaspora vineae applied to winemaking because of their high oenological potential in aroma and fermentation performance were selected to obtain high-quality genomes. Here, we present a phylogenetic analysis and the complete transcriptome and aroma metabolome of H. vineae during three fermentation steps. This species produced significantly richer flavor compound diversity than Saccharomyces, including benzenoids, phenylpropanoids, and acetate-derived compounds. The identification of six proteins, different from S. cerevisiae ATF, with diverse acetyltransferase domains in H. vineae offers a relevant source of native genetic variants for this enzymatic activity. The discovery of benzenoid synthesis capacity in H. vineae provides a new eukaryotic model to dilucidate an alternative pathway to that catalyzed by plants' phenylalanine lyases.

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Poly-extremophiles microorganisms have the capacity to inhabit hostile environments and can survive several adverse conditions that include as variations in temperature, pH, and salinity, high levels UV light and atmospheric pressure, and even the presence of toxic compounds and the formation of reactive oxygen species (ROS). A halotolerant Exiguobacterium strain was isolated from Salar de Huasco (Chilean Altiplano), a well-known shallow lake area with variable salinity levels, little human intervention, and extreme environmental conditions, which makes it ideal for the study of resistant mechanisms and the evolution of adaptations. This bacterial genus has not been extensively studied, although its cosmopolitan location indicates that it has high levels of plasticity and adaptive capacity. However, to date, there are no studies regarding the tolerance and resistance to salinity and osmotic pressure. We set out to characterize the Exiguobacterium sp. SH31 strain and describe its phenotypical and genotypical response to osmotic stress. In this context, as a first step to characterize the response to the SH31 strain to salinity and to establish the bases for a molecular study, we proposed to compare its response under three salt conditions (0, 25, and 50 g/l NaCl). Using different physiology, genomic, and transcriptomic approaches, we determined that the bacterium is able to grow properly in a NaCl concentration of up to 50 g/l; however, the best growth rate was observed at 25 g/l. Although the presence of flagella is not affected by salinity, motility was diminished at 25 g/l NaCl and abolished at 50 g/l. Biofilm formation was induced proportionally with increases in salinity, which was expected. These phenotypic results correlated with the expression of related genes: fliG and fliS Motility); opuBA and putP (transport); glnA, proC, gltA, and gbsA (compatible solutes); ywqC, bdlA, luxS y pgaC (biofilm and stress response); and therefore, we conclude that this strain effectively modifies gene expression and physiology in a differential manner when faced with different concentrations of NaCl and these modifications aid survival.

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A novel actinobacterium, strain DB165T, was isolated from cold waters of Llullaillaco Volcano Lake (6170 m asl) in Chile. Phylogenetic analysis based on 16S rRNA gene sequences identified strain DB165T as belonging to the genus Subtercola in the family Microbacteriaceae, sharing 97.4% of sequence similarity with Subtercola frigoramans DSM 13057T, 96.7% with Subtercola lobariae DSM 103962T, and 96.1% with Subtercola boreus DSM 13056T. The cells were observed to be Gram-positive, form rods with irregular morphology, and to grow best at 10-15 °C, pH 7 and in the absence of NaCl. The cross-linkage between the amino acids in its peptidoglycan is type B2γ; 2,4-diaminobutyric acid is the diagnostic diamino acid; the major respiratory quinones are MK-9 and MK-10; and the polar lipids consist of phosphatidylglycerol, diphosphatidylglycerol, 5 glycolipids, 2 phospholipids and 5 additional polar lipids. The fatty acid profile of DB165T (5% >) contains iso-C14:0, iso-C16:0, anteiso-C15:0, anteiso-C17:0, and the dimethylacetal iso-C16:0 DMA. The genomic DNA G+C content of strain DB165T was determined to be 65 mol%. Based on the phylogenetic, phenotypic, and chemotaxonomic analyses presented in this study, strain DB165T (= DSM 105013T = JCM 32044T) represents a new species in the genus Subtercola, for which the name Subtercola vilae sp. nov. is proposed.

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ResumenJustificación y objetivo:Algunos estudios han documentado mayor riesgo de eventos cardiovasculares en pacientes con neumonía adquirida en la comunidad. El objetivo del estudio es caracterizar la población de pacientes con diagnóstico de neumonía adquirida en la comunidad e identificar factores relacionados con el desarrollo de complicaciones cardiovasculares y muerte a 30 días.Métodos:se realizó un estudio observacional de cohorte retrospectivo con casos y controles en el Servicio de Medicina Interna en un hospital universitario de nivel terciario, con pacientes con diagnóstico de neumonía adquirida en la comunidad. Se evaluaron variables clínicas y de laboratorio de los pacientes ingresados, así como diagnóstico clínico de arritmia, infarto agudo de miocardio, insuficiencia cardiaca de nuevo, o empeoramiento de cuadro preexistente, edema pulmonar y muerte en los 30 días posteriores al ingreso (casos), o ausencia de estos hallazgos (controles).Resultados:se identificó 35 casos de neumonía adquirida en la comunidad, de los cuales 17 presentaron complicaciones cardiovasculares (48,57%). Los pacientes de mayor edad, de sexo femenino, hipertensos y cardiópatas isquémicos, tuvieron mayor riesgo de eventos cardiovasculares, así como los que presentaron al ingreso mayores valores de presión sistólica, creatin fosfokinasa y nitrógeno ureico. El 22,85% de los pacientes falleció en los siguientes 30 días posteriores al ingreso por neumonía; el riesgo de muerte fue mayor para los pacientes con complicaciones cardiovasculares [Hazard ratio 8,8 (IC95% 1,08-71,66; p=0,03)]. No se encontró asociación entre las diferencias clínicas identificadas y el desenlace fatal. Limitaciones: las variables se tomaron de los expedientes clínicos, dependiendo completamente del criterio de los médicos tratantes para solicitud de exámenes y asignación de variables. Es posible la presencia de factores de confusión debido a covariables no medidas o severidad de la enfermedad.Conclusión:en los pacientes internados con diagnóstico de neumonía adquirida en la comunidad, el desarrollo de complicaciones cardiovasculares se asoció con aumento de mortalidad.

AbstractJustification and objectives:Previous studies have demonstrated increased risk of cardiovascular events in patients with community-acquired pneumonia. The objective of this study is to characterize the population of patients diagnosed with community-acquired pneumonia and identify factors associated with the development of cardiovascular complications and 30-day mortality.Methods:A retrospective observational case-control cohort was done, with cases and controls in the department of Internal Medicine at a tertiary level teaching hospital with patients diagnosed with community-acquired pneumonia. Clinical and laboratory variables of patients admitted were evaluated, also the clinical diagnosis of arrhythmia, acute myocardial infarction, heart failure (new or worsening), pulmonary edema and death within 30 days after admission (cases) or absence of these findings (controls).Results:35 cases of community-acquired pneumonia were identified on the first semester of 2015, of which 17 (48.57%) developed cardiovascular complications. Older patients, female sex, hypertension and ischemic heart disease demonstrated higher risk of cardiovascular events, as well as presenting the systolic blood pressure, creatine phosphokinase and urea nitrogen. The 22.85% of patients died within 30 days after being admitted; the risk of death was higher for patients with cardiovascular complications [Hazard ratio 8.8 (95% CI 1.08-71.66; p = 0.03)]. No association between the identified clinical differences and fatal outcome was found. Limitations:The retrospective nature of the study and the variables, which were collected from clinical records, depended entirely on the discretion of the treating physicians to request tests and variable allocation. The presence of confounding is possible due to unmeasured covariates or disease severity.Conclusions:In patients admitted with a diagnosis of community-acquired pneumonia the development of cardiovascular complications was associated with increased mortality.

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The Atacama Desert hosts diverse ecosystems including salt flats and shallow Andean lakes. Several heavy metals are found in the Atacama Desert, and microorganisms growing in this environment show varying levels of resistance/tolerance to copper, tellurium, and arsenic, among others. Herein, we report the genome sequence and comparative genomic analysis of a new Exiguobacterium strain, sp. SH31, isolated from an altiplanic shallow athalassohaline lake. Exiguobacterium sp. SH31 belongs to the phylogenetic Group II and its closest relative is Exiguobacterium sp. S17, isolated from the Argentinian Altiplano (95% average nucleotide identity). Strain SH31 encodes a wide repertoire of proteins required for cadmium, copper, mercury, tellurium, chromium, and arsenic resistance. Of the 34 Exiguobacterium genomes that were inspected, only isolates SH31 and S17 encode the arsenic efflux pump Acr3. Strain SH31 was able to grow in up to 10 mM arsenite and 100 mM arsenate, indicating that it is arsenic resistant. Further, expression of the ars operon and acr3 was strongly induced in response to both toxics, suggesting that the arsenic efflux pump Acr3 mediates arsenic resistance in Exiguobacterium sp. SH31.

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Transient and highly regulated elevations of cytosolic Ca2+ control a variety of cellular processes. Bulk measurements using radioactive Ca2+ and the luminescent sensor aequorin have shown that in response to pheromone, budding yeast cells undergo a rise of cytosolic Ca2+ that is mediated by two import systems composed of the Mid1-Cch1-Ecm7 protein complex and the Fig1 protein. Although this response has been widely studied, there is no treatment of Ca2+ dynamics at the single-cell level. Here, using protein calcium indicators, we show that both vegetative and pheromone-treated yeast cells exhibit discrete and asynchronous Ca2+ bursts. Most bursts reach maximal amplitude in 1-10 s, range between 7 and 30 s, and decay in a way that fits a single-exponential model. In vegetative cells, bursts are scarce but preferentially occur when cells are transitioning G1 and S phases. On pheromone presence, Ca2+ burst occurrence increases dramatically, persisting during cell growth polarization. Pheromone concentration modulates burst frequency in a mechanism that depends on Mid1, Fig1, and a third, unidentified, import system. We also show that the calcineurin-responsive transcription factor Crz1 undergoes nuclear localization bursts during the pheromone response.

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Benzyl alcohol and other benzenoid-derived metabolites of particular importance in plants confer floral and fruity flavors to wines. Among the volatile aroma components in Vitis vinifera grape varieties, benzyl alcohol is present in its free and glycosylated forms. These compounds are considered to originate from grapes only and not from fermentative processes. We have found increased levels of benzyl alcohol in red Tannat wine compared to that in grape juice, suggesting de novo formation of this metabolite during vinification. In this work, we show that benzyl alcohol, benzaldehyde, p-hydroxybenzaldehyde, and p-hydroxybenzyl alcohol are synthesized de novo in the absence of grape-derived precursors by Hanseniaspora vineae. Levels of benzyl alcohol produced by 11 different H. vineae strains were 20-200 times higher than those measured in fermentations with Saccharomyces cerevisiae strains. These results show that H. vineae contributes to flavor diversity by increasing grape variety aroma concentration in a chemically defined medium. Feeding experiments with phenylalanine, tryptophan, tyrosine, p-aminobenzoic acid, and ammonium in an artificial medium were tested to evaluate the effect of these compounds either as precursors or as potential pathway regulators for the formation of benzenoid-derived aromas. Genomic analysis shows that the phenylalanine ammonia-lyase (PAL) and tyrosine ammonia lyase (TAL) pathways, used by plants to generate benzyl alcohols from aromatic amino acids, are absent in the H. vineae genome. Consequently, alternative pathways derived from chorismate with mandelate as an intermediate are discussed.

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