Natural occurring epialleles determine vitamin E accumulation in tomato fruits

Vitamin E (VTE) content is a low heritability nutritional trait for which the genetic determinants are poorly understood. Here, we focus on a previously detected major tomato VTE quantitative trait loci (QTL; mQTL9-2-6) and identify the causal gene as one encoding a 2-methyl-6-phytylquinol methyltransferase (namely VTE3(1)) that catalyses one of the final steps in the biosynthesis of γ- and α-tocopherols, which are the main forms of VTE. By reverse genetic approaches, expression analyses, siRNA profiling and DNA methylation assays, we demonstrate that mQTL9-2-6 is an expression QTL associated with differential methylation of a SINE retrotransposon located in the promoter region of VTE3(1). Promoter DNA methylation can be spontaneously reverted leading to different epialleles affecting VTE3(1) expression and VTE content in fruits. These findings indicate therefore that naturally occurring epialleles are responsible for regulation of a nutritionally important metabolic QTL and provide direct evidence of a role for epigenetics in the determination of agronomic traits.L.Q. was recipient of a fellowship of Agencia Nacional de Promoción Científica y Tecnológica and Consejo Nacional de Investigaciones Científicas y Técnicas in Argentina and supported by a postdoctral fellowship from Investissements d’Avenir ANR-10-LABX-54 MEMO LIFE in France. J.A. and L.B. were recipients of a fellowship of Fundação à Amparo da Pesquisa do Estado de São Paulo (Brazil). J.V.C.d.S. was recipient of a fellowship of Conselho Nacional de Desenvolvimento Científico e Tecnológico (Brazil). R.A., L.B. and F.C. are members of Consejo Nacional de Investigaciones Científicas y Técnicas (Argentina). This work was carried out in compliance with current laws governing genetic experimentation in Brazil and in Argentina. This work was supported with grants from Instituto Nacional de Tecnologia Agropecuária, Consejo Nacional de Investigaciones Científicas y Técnicas and Agencia Nacional de Promoción Científica y Tecnológica (Argentina), Fundação à Amparo da Pesquisa do Estado de São Paulo, Conselho Nacional de Desenvolvimento Científico e Tecnológico and Universidade de São Paulo (Brazil); Max Planck Society (Germany); the Agence Nationale de la Recherche (Investissements d’Avenir ANR-10-LABX-54 MEMO LIFE and ANR-11-IDEX-0001-02 PSL* Research University to V.C.); and the European Union (EpiGeneSys FP7 Network of Excellence number 257082 to V.C. and the European Solanaceae Integrated Project FOOD-CT-2006-016214 to F.C., M.R. and A.R.F.)

Physiological and proteomic response of Escherichia coli O157:H7 to a bioprotective lactic acid bacterium in a meat environment

The enterohemorrhagic Escherichia (E.) coli (EHEC) is a pathogen of great concern for public health and the meat industry all over the world. The high economic losses in meat industry and the high costs of the illness highlight the necessity of additional efforts to control this pathogen. Previous studies have demonstrated the inhibitory activity of Enterococcus mundtii CRL35 towards EHEC, showing a specific proteomic response during the co-culture. In the present work, additional studies of the EHEC-Ent. mundtii interaction were carried out: i) differential protein expression of E. coli O157:H7 NCTC12900 growing in co-culture with Ent. mundtii in a meat environment, ii) the reciprocal influence between these two microorganisms in the adhesion to extracellular matrix (ECM) proteins and iii) the possible induction of the phage W933, coding for Shiga toxin (Stx1), by Ent. mundtii CRL35. Proteomic analysis showed a significant repression of a number of E. coli NCTC12900 proteins in co-culture respect to its single culture, these mostly related to the metabolism and transport of amino acids and nucleotides. On the other hand, statistically significant overexpression of EHEC proteins involved in stress, energy production, amino acid metabolism and transcription was observed at 30 h respect to 6 h when EHEC grew in co-culture. Data are available via ProteomeXchange with identifier PXD014588. Besides, EHEC showed a decreased adhesion capacity to ECM proteins in the presence of the bioprotective strain. Finally, Ent. mundtii CRL35 did not induce the lytic cycle of W933 bacteriophage, thus indicating its potential safe use for eliminating this pathogen. Overall, this study expands the knowledge of EHEC- Ent. mundtii CRL35 interaction in a meat environment, which will certainly contribute to find out effective biological strategies to eliminate this pathogen.Fil: Orihuel, Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; ArgentinaFil: Teran, Lucrecia Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; ArgentinaFil: Renaut, Jenny. Luxembourg Institute of Science and Technology; LuxemburgoFil: Planchon, Sébastien. Luxembourg Institute of Science and Technology; LuxemburgoFil: Valacco, Maria Pia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales; ArgentinaFil: Masias, Ruth Emilse. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Investigaciones Biológicas. Universidad Nacional de Tucumán. Instituto Superior de Investigaciones Biológicas; ArgentinaFil: Minahk, Carlos Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Investigaciones Biológicas. Universidad Nacional de Tucumán. Instituto Superior de Investigaciones Biológicas; ArgentinaFil: Vignolo, Graciela Margarita. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; ArgentinaFil: Moreno, Silvia Margarita. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales; ArgentinaFil: Almeida, André Martinho de. Universidade de Lisboa; PortugalFil: Saavedra, Maria Lucila. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; ArgentinaFil: Fadda, Silvina G.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; Argentin

Avaliação de Ibicella lutea como agente antimicrobiano frente à Staphylococcus aureus

Justificativa e Objetivos: O estudo objetivou a avaliação da atividade antibacteriana de extratos brutos e frações de Ibicella lutea, na inibição do crescimento de Staphylococcus aureus, avaliando a combinação destes compostos e sua atividade citotóxica. Métodos: Para a atividade antibacteriana dos extratos foi utilizado o Teste de Microdiluição em Caldo, seguido do Teste Checkerboard. Os extratos que apresentaram atividade antibacteriana foram submetidos ao teste de citotoxicidade, com células macrofágicas e determinação do seu Índice de Seletividade (IS). Resultados: A fração de acetato de etila(AcOE) obteve o melhor potencial antibacteriano (6,25 µg/mL), entretanto nenhum dos compostos testados apresentaram atividade bactericida nas concentrações empregadas. Neste estudo pode-se observar uma ação aditiva entre as frações AcOE e metanólica (MeOH), sendo a interação entre os extratos brutos indiferente. De acordo com o teste de citotoxicidade, a fração AcOE apresentou uma maior índice de sobrevivência das células macrofágicas (IC50%=30,35 µg/mL). Entretanto, quando calculado o IS, não houve resultados satisfatórios (IS < 10) para os extratos analisados. Conclusões: Neste estudo observou-se o potencial antibacteriano das frações AcOE e MeOH, assim como uma ação aditiva na combinação das frações, dando suporte para o isolamento e caracterização de seus componentes ativos. Apesar dos extratos não apresentarem um IS satisfatório, novos estudos de toxicidade devem ser realizados para determinar com segurança o potencial de uso dos produtos provenientes de I. lutea, como é o caso de medicamentos para uso tópico ou biocidas

Avaliação de Ibicella lutea como agente antimicrobiano frente à Staphylococcus aureus

Justificative and Objectives: the study aimed the assessment of the antibacterial activity of crude extracts and fractions of Ibicella lutea, front Staphylococcus aureus, thecombination of these compounds and cytotoxic activity. Methods: was used for antibacterial activity the Microdilution Test Broth, and performed the Checkerboard Test. The extracts showed antibacterial activity were submitted to the citotoxicity test, with macrophages cell and determination of the Selectivity Index (SI). Results: The acetate etila fraction (AcOE) was better antimicrobial activity (6.25 µg/mL) compared with the others extracts and fractions used, however none of the compounds showed bactericidal activity in concentrations employed. In present study, we can be observed an additive activity between AcOE and methanolic (MeOH) fractions, and indifferent interaction between crude extracts. According to citotoxicity test, the extract which led to a higher survival rate of macrophage cells was the fraction AcOE (IC50%=30.35 µg/mL). However, when the calculated SI no satisfactory results (SI < 10) to any of the extracts was observed. Conclusions: in the present study we can observe an antimicrobial activity of the fractions AcOE and MeOH to S. aureus, as well as an additive this potential when the fractions are combined, providing support from isolation and characterization of yours active components. Despite the extracts did not showed a satisfactory SI, new toxicity studies should be performed to establish the potential use of safety with the products derived from I. lutea, such as drugs for topical and biocide products.Justificativa e Objetivos: O estudo objetivou a avaliação da atividade antibacteriana de extratos brutos e frações de Ibicella lutea, na inibição do crescimento de Staphylococcus aureus, avaliando a combinação destes compostos e sua atividade citotóxica. Métodos: Para a atividade antibacteriana dos extratos foi utilizado o Teste de Microdiluição em Caldo, seguido do Teste Checkerboard. Os extratos que apresentaram atividade antibacteriana foram submetidos ao teste de citotoxicidade, com células macrofágicas e determinação do seu Índice de Seletividade (IS). Resultados: A fração de acetato de etila(AcOE) obteve o melhor potencial antibacteriano (6,25 µg/mL), entretanto nenhum dos compostos testados apresentaram atividade bactericida nas concentrações empregadas. Neste estudo pode-se observar uma ação aditiva entre as frações AcOE e metanólica (MeOH), sendo a interação entre os extratos brutos indiferente. De acordo com o teste de citotoxicidade, a fração AcOE apresentou uma maior índice de sobrevivência das células macrofágicas (IC50%=30,35 µg/mL). Entretanto, quando calculado o IS, não houve resultados satisfatórios (IS < 10) para os extratos analisados. Conclusões: Neste estudo observou-se o potencial antibacteriano das frações AcOE e MeOH, assim como uma ação aditiva na combinação das frações, dando suporte para o isolamento e caracterização de seus componentes ativos. Apesar dos extratos não apresentarem um IS satisfatório, novos estudos de toxicidade devem ser realizados para determinar com segurança o potencial de uso dos produtos provenientes de I. lutea, como é o caso de medicamentos para uso tópico ou biocidas

Spectroscopic and Asteroseismic Analysis of the Secondary Clump Red Giant HD 226808*

In order to clarify the properties of the secondary clump star HD 226808 (KIC 5307747), we combined four years of data from Kepler space photometry with high-resolution spectroscopy of the High Efficiency and Resolution Mercator Échelle Spectrograph mounted on the Mercator telescope. The fundamental atmospheric parameters, radial velocities, rotation velocities, and elemental abundance for Fe and Li were determined by analyzing line strengths and fitting-line profiles, based on a 1D local thermodynamic equilibrium model atmosphere. Second, we analyzed a photometric light curve obtained by Kepler and we extracted asteroseismic data of this target using Lets Analysis, Use and Report of Asteroseismology, a new seismic tool developed for the study of evolved FGK solar-like stars. We determined the evolutionary status and effective temperature, surface gravity, metallicity, microturbulence, and chemical abundances for Li, Ti, Fe, and Ni for HD 226808, by employing spectroscopy, asteroseismic scaling relations, and evolutionary structure models built in order to match observed data. Our results also show that an accurate synergy between good spectroscopic analysis and asteroseismology can provide a jump toward understanding evolved stars

The Fluorescence Detector of the Pierre Auger Observatory

The Pierre Auger Observatory is a hybrid detector for ultra-high energy cosmic rays. It combines a surface array to measure secondary particles at ground level together with a fluorescence detector to measure the development of air showers in the atmosphere above the array. The fluorescence detector comprises 24 large telescopes specialized for measuring the nitrogen fluorescence caused by charged particles of cosmic ray air showers. In this paper we describe the components of the fluorescence detector including its optical system, the design of the camera, the electronics, and the systems for relative and absolute calibration. We also discuss the operation and the monitoring of the detector. Finally, we evaluate the detector performance and precision of shower reconstructions.Comment: 53 pages. Submitted to Nuclear Instruments and Methods in Physics Research Section

Cabbage and fermented vegetables : From death rate heterogeneity in countries to candidates for mitigation strategies of severe COVID-19

Large differences in COVID-19 death rates exist between countries and between regions of the same country. Some very low death rate countries such as Eastern Asia, Central Europe, or the Balkans have a common feature of eating large quantities of fermented foods. Although biases exist when examining ecological studies, fermented vegetables or cabbage have been associated with low death rates in European countries. SARS-CoV-2 binds to its receptor, the angiotensin-converting enzyme 2 (ACE2). As a result of SARS-CoV-2 binding, ACE2 downregulation enhances the angiotensin II receptor type 1 (AT(1)R) axis associated with oxidative stress. This leads to insulin resistance as well as lung and endothelial damage, two severe outcomes of COVID-19. The nuclear factor (erythroid-derived 2)-like 2 (Nrf2) is the most potent antioxidant in humans and can block in particular the AT(1)R axis. Cabbage contains precursors of sulforaphane, the most active natural activator of Nrf2. Fermented vegetables contain many lactobacilli, which are also potent Nrf2 activators. Three examples are: kimchi in Korea, westernized foods, and the slum paradox. It is proposed that fermented cabbage is a proof-of-concept of dietary manipulations that may enhance Nrf2-associated antioxidant effects, helpful in mitigating COVID-19 severity.Peer reviewe

Nrf2-interacting nutrients and COVID-19 : time for research to develop adaptation strategies

There are large between- and within-country variations in COVID-19 death rates. Some very low death rate settings such as Eastern Asia, Central Europe, the Balkans and Africa have a common feature of eating large quantities of fermented foods whose intake is associated with the activation of the Nrf2 (Nuclear factor (erythroid-derived 2)-like 2) anti-oxidant transcription factor. There are many Nrf2-interacting nutrients (berberine, curcumin, epigallocatechin gallate, genistein, quercetin, resveratrol, sulforaphane) that all act similarly to reduce insulin resistance, endothelial damage, lung injury and cytokine storm. They also act on the same mechanisms (mTOR: Mammalian target of rapamycin, PPAR gamma:Peroxisome proliferator-activated receptor, NF kappa B: Nuclear factor kappa B, ERK: Extracellular signal-regulated kinases and eIF2 alpha:Elongation initiation factor 2 alpha). They may as a result be important in mitigating the severity of COVID-19, acting through the endoplasmic reticulum stress or ACE-Angiotensin-II-AT(1)R axis (AT(1)R) pathway. Many Nrf2-interacting nutrients are also interacting with TRPA1 and/or TRPV1. Interestingly, geographical areas with very low COVID-19 mortality are those with the lowest prevalence of obesity (Sub-Saharan Africa and Asia). It is tempting to propose that Nrf2-interacting foods and nutrients can re-balance insulin resistance and have a significant effect on COVID-19 severity. It is therefore possible that the intake of these foods may restore an optimal natural balance for the Nrf2 pathway and may be of interest in the mitigation of COVID-19 severity