492 research outputs found
"Poppy" yeast
I am old enough to have taken part in the international project to sequence the first eukaryotic genome—that of Saccharomyces cerevisiae—which was released in 1996. Twenty years later, scientists from academic and commercial institutions are now involved in the first wholesale construction of a eukaryotic genome: the Yeast 2.0 Project 1. The construction of whole genomes from scratch is defined as a bottom-up approach in synthetic biology. One of the aims of such work is to reduce genome size and construct a minimal cell factory for industrial applications. These synthetic yeast chromosomes will have unique features to allow scientists to easily reshuffle, eliminate or add new genes 2 in order to engineer cells for efficient production of a desired compound. Synthetic biologists also use a top-down approach to insert functional biological components into natural genomes. This has been used in yeast to produce natural molecules of pharmaceutical value, such as artemisinin acid 3. Currently, many compounds are not chemically synthesized because it is cheaper and more efficient to extract them from plants. The products of synthetic biology could easily replace plants as the source, especially as yeast fermentation is a matter of days, while plants need months or years to grow
The divine spirit of bees. A note on honey and the origins of yeast-driven fermentation
One of the earliest domesticated organisms is perhaps the eukaryote microorganism known as Saccharomyces cerevisiae, or more simply “the yeast”. Its decisive role in triggering fermentation as a process useful for agricultural products preservation and transformation into consumable food, though known from the Palaeolithic in the ancient Near East, became decisive in the Neolithic Period. The earliest agriculturalists of the Fertile Crescent accidentally triggered fermentation with the addition of honey to fruits juices, as attested to in the archaeological record. The yeast, that lives inside the guts of bees and wasps, is responsible for this fermentation process. Honey contains both yeast and sugar that facilitates its growth generating fermentation. The creative capability of the bees let these insects to be credited of a divine skill
The central role of gut microbiota in drug metabolism and personalized medicine
The gut microbiota is now considered as a symbiotic organ playing an important role in human health and disease
development and has been recently recognized as a modulator of drug metabolism and toxicity. Here, we briefly
discuss new findings describing how the gut microbiota is now considered to be a central player in drug metabolism
and personalized medicine
Gaijin de Matayoshi y Yamasaki: un mismo nombre para dos experiencias
La novela de Maximiliano Matayoshi, Gaijin (2002), el film homónimo, Gaijin: Os caminhos da Libertade (1980), y su posterior versión, Gaijin, amame como seu (2005), de Tizuka Yamasaki, se acercan al tema de la inmigración japonesa y los problemas de asimilación experimentados al llegar a Argentina y Brasil, respectivamente. Si bien las perspectivas del autor y la directora difieren, existe un marco común en ambas obras por medio del autor y la directora, respectivamente. Por ser nikkei (descendientes de japoneses), ambos son capaces de entrar y salir de la realidad del individuo inmigrante japonés. El presente análisis se centra en la dinámica de la inmigración japonesa y cómo se comparten los espacios, y cómo las experiencias culturales incidieron en el proceso de asimilación en el nuevo lugar
Eva Perón: el poder del deseo
El estudio del cuerpo y en sus diversas formas y contextos debe abordarse desde una perspertiva interdisiplinaria que incluye desde el arte y la literatura hasta la medicina y las artes plásticas en búsqueda constante de la significación social del mismo. María Eva Duarte de Perón (1919-1952) fue el centro de una serie de eventos que no solo cambiaron el rumbo de su vida sino también el del mundo político y social de Argentina. Su vida se llama a la observación, el análisis y la búsqueda de respuestas a cómo una simple e ilegítima niña logró llegar a las más altas cumbres de la sociedad argentina. La capacidad de Eva para adaptarse y sobrepasar contratiempos conjuntamente con su estilo único y astucia la catapultaron al estrellato marcando la memoria del pueblo argentino y la comunidad internacional. Dentro de vasto material literario y artístico sobre la vida y obra de Eva, se pueden mencionar: Eva Perón (1970) de Otelo Borroni y Roberto Vacca, La pasión según Eva (1994) de Abel Posse, Eva Perón, the bibliography (1995) de Alicia Dujovne Ortíz, El misterio de Eva Perón (1988,documental) de Tulio Demicheli, Evita Pre-Madonna (1995, documental) de Claudia Nie, Santa Evita (1995) de Tomás Eloy Martínez, Evita (1996, film) de Alan Parker y Evita: Santa o Demonio (1996, film) de Juan Carlos de Sanzo. Tendiente a iluminar la vida de Eva Perón desde su conexión con el poder, observaremos el uso del cuerpo (como discurso político), la creación del mito y el mito dentro del mit
"PUTTING YOURSELF IN OTHER PEOPLE'S SHOES": FROM MEASURES TO APPLICATIONS
Questa tesi approfondisce, da un punto di vista teorico e applicativo, l’analisi della capacità di “mettersi nei panni degli altri”definita come un costrutto life-span, si sviluppa dalla prima infanzia ma non smette di evolversi fino all’età adulta. La sua traiettoria evolutiva è legata al contesto, alle interazioni, alle esperienze e allo sviluppo cognitivo ed emotivo degli individui.
Dalla letteratura emerge come tale capacità sia spesso oggetto di sovrapposizioni concettuali con altri costrutti della psicologia dello sviluppo come la “Teoria della Mente" (Premack & Woodruff, 1978; Wimmer & Perner, 1985), detta anche "mindreading" (Baron-Cohen, Jolliffe, Mortimore & Robertson, 1997); il "perspective-taking" (Carpendale & Lewis, 2006; Moll & Meltzoff, 2011; Sullivan, Bennett, Carpenter & Lewis, 2008); la "funzione riflessiva" (Fonagy & Target, 1997); e la "mentalizzazione" (Fonagy, Bateman & Luyten, 2012). Grazie all’approfondimento di tali costrutti, si arriva a comprendere essi siano spesso declinati con il concetto di mentalizzazione, che viene analizzato nella sua evoluzione storica e in relazione ad altri costrutti come il legame di attaccamento (Bowlby, 1969) e la mind-mindedness (Meins, 2002). L’analisi del costrutto prosegue con la presentazione di tre lavori di ricerca che lo esplorano, da un punto di vista teorico (i primi due) e applicativo (il terzo), dalla sua massima evoluzione nell’età adulta fino al suo manifestarsi e potenziarsi in età evolutiva.
La prima ricerca si concentra sulla validazione italiana di una scala che misura l'affettività mentalizzata, un costrutto che integra nel processo di regolazione delle emozioni la mentalizzazione in età adulta. La seconda verifica come la capacità di "mettersi nei panni degli altri", consolidata in preadolescenza, si manifesta all'interno dei legami di attaccamento tra bambini e insegnanti e infine, il terzo lavoro studia se tale capacità possa essere migliorata nel contesto scolastico e avere un impatto sui costrutti relazionali e sociali legati al processo decisionale in campo economico, come l'equità, l'altruismo e la donazione.This thesis explores, from a theoretical and applicative perspective, the ability to "put oneself in the shoes of others", defined as a life-span construct, which develops from early childhood but does not stop evolving until adulthood. Its developmental trajectory is linked to the context, interactions, experiences and cognitive and emotional development of individuals.
The literature shows how this capacity is often the subject of conceptual overlaps with other constructs of developmental psychology such as the "Theory of Mind" (Premack & Woodruff, 1978; Wimmer & Perner, 1985), also known as "mindreading" (Baron-Cohen, Jolliffe, Mortimore & Robertson, 1997); perspective-taking (Carpendale & Lewis, 2006; Moll & Meltzoff, 2011; Sullivan, Bennett, Carpenter & Lewis, 2008); the "reflective function" (Fonagy & Target, 1997); and "mentalisation" (Fonagy, Bateman & Luyten, 2012). Thanks to the in-depth study of these constructs, we come to understand that they are often declined with the concept of mentalisation, which is analysed in its historical evolution and in relation to other constructs such as the attachment bond (Bowlby, 1969) and mind-mindedness (Meins, 2002). The analysis of the construct continues with the presentation of three research works that explore it, from a theoretical point of view (the first two) and from an applicative point of view (the third), from its maximum evolution in adulthood to its manifestation and enhancement in developmental age.
The first research focuses on the Italian validation of a scale measuring mentalized affectivity, a construct that integrates mentalization in adulthood into the process of emotion regulation. The second examines how the ability to "put oneself in the shoes of others", which is consolidated in preadolescence, manifests itself within the attachment bonds between children and teachers and finally, the third work studies whether this ability can be improved in the school context and have an impact on relational and social constructs linked to economic decision-making, such as fairness, altruism and donation
Ergosterol reduction impairs mitochondrial DNA maintenance in S. cerevisiae
Sterols are essential lipids, involved in many biological processes. In Saccharomyces cerevisiae, the enzymes of the ergosterol biosynthetic pathway (Erg proteins) are localized in different cellular compartments. With the aim of studying organelle interactions, we discovered that Erg27p resides mainly in Lipid Droplets (LDs) in respiratory competent cells, while in absence of respiration, is found mostly in the ER. The results presented in this paper demonstrate an interplay between the mitochondrial respiration and ergosterol production: on the one hand, rho° cells show lower ergosterol content when compared with wild type respiratory competent cells, on the other hand, the ergosterol biosynthetic pathway influences the mitochondrial status, since treatment with ketoconazole, which blocks the ergosterol pathway, or the absence of the ERG27 gene, induced rho° production in S. cerevisiae. The loss of mitochondrial DNA in the ∆erg27 strain is fully suppressed by exogenous addition of ergosterol. These data suggest the notion that ergosterol is essential for maintaining the mitochondrial DNA attached to the inner mitochondrial membrane
The hypoxic transcription factor KlMga2 mediates the response to oxidative stress and influences longevity in the yeast Kluyveromyces lactis
Hypoxia is defined as the decline of oxygen availability, depending on environmental supply and cellular consumption rate. The decrease in O2 results in reduction of available energy in facultative aerobes. The response and/or adaptation to hypoxia and other changing environmental conditions can influence the properties and functions of membranes by modifying lipid composition. In the yeast Kluyveromyces lactis, the KlMga2 gene is a hypoxic regulatory factor for lipid biosynthesis-fatty acids and sterols-and is also involved in glucose signaling, glucose catabolism and is generally important for cellular fitness. In this work we show that, in addition to the above defects, the absence of the KlMGA2 gene caused increased resistance to oxidative stress and extended lifespan of the yeast, associated with increased expression levels of catalase and SOD genes. We propose that KlMga2 might also act as a mediator of the oxidative stress response/adaptation, thus revealing connections among hypoxia, glucose signaling, fatty acid biosynthesis and ROS metabolism in K. lactis
The proteasome lid triggers COP9 signalosome activity during the transition of Saccharomyces cerevisiae cells into quiescence.
The class of Cullin–RING E3 ligases (CRLs) selectively ubiquitinate a large portion of proteins targeted for proteolysis by the 26S proteasome. Before degradation, ubiquitin molecules are removed from their conjugated proteins by deubiquitinating enzymes, a handful of which are associated with the proteasome. The CRL activity is triggered by modification of the Cullin subunit with the ubiquitin-like protein, NEDD8 (also known as Rub1 in Saccharomyces cerevisiae). Cullin modification is then reversed by hydrolytic action of the COP9 signalosome (CSN). As the NEDD8– Rub1 catalytic cycle is not essential for the viability of S. cerevisiae, this organism is a useful model system to study the alteration of Rub1–CRL conjugation patterns. In this study, we describe two distinct mutants of Rpn11, a proteasome-associated deubiquitinating enzyme, both of which exhibit a biochemical phenotype characterized by high accumulation of Rub1-modified Cdc53–Cullin1 (yCul1) upon entry into quiescence in S. cerevisiae. Further characterization revealed proteasome 19S-lid-associated deubiquitination activity that authorizes the hydrolysis of Rub1 from yCul1 by the CSN complex. Thus, our results suggest a negative feedback mechanism via proteasome capacity on upstream ubiquitinating enzymes
A role for microbial selection in frescoes' deterioration in Tomba degli Scudi in Tarquinia, Italy
Mural paintings in the hypogeal environment of the Tomba degli Scudi in Tarquinia, Italy, show a quite
dramatic condition: the plaster mortar lost his cohesion and a white layer coating is spread over almost
all the wall surfaces. The aim of this research is to verify if the activity of microorganisms could be one of
the main causes of deterioration and if the adopted countermeasures (conventional biocide treatments)
are sufficient to stop it. A biocide treatment of the whole environment has been carried out before the
conservative intervention and the tomb has been closed for one month. When the tomb was opened
again, we sampled the microorganisms present on the frescoes and we identified four Bacillus species
and one mould survived to the biocide treatment. These organisms are able to produce spores, a highly
resistant biological form, which has permitted the survival despite the biocide treatment. We show
that these Bacillus strains are able to produce calcium carbonate and could be responsible for the white
deposition that was damaging and covering the entire surface of the frescoes. Our results confirm that
the sanitation intervention is non always resolutive and could even be deleterious in selecting harmful
microbial communities
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