Summary
We sequenced the genome of the highly heterozygous almond Prunus dulcis cv. Texas combining short‐ and long‐read sequencing. We obtained a genome assembly totaling 227.6 Mb of the estimated ...almond genome size of 238 Mb, of which 91% is anchored to eight pseudomolecules corresponding to its haploid chromosome complement, and annotated 27 969 protein‐coding genes and 6747 non‐coding transcripts. By phylogenomic comparison with the genomes of 16 additional close and distant species we estimated that almond and peach (Prunus persica) diverged around 5.88 million years ago. These two genomes are highly syntenic and show a high degree of sequence conservation (20 nucleotide substitutions per kb). However, they also exhibit a high number of presence/absence variants, many attributable to the movement of transposable elements (TEs). Transposable elements have generated an important number of presence/absence variants between almond and peach, and we show that the recent history of TE movement seems markedly different between them. Transposable elements may also be at the origin of important phenotypic differences between both species, and in particular for the sweet kernel phenotype, a key agronomic and domestication character for almond. Here we show that in sweet almond cultivars, highly methylated TE insertions surround a gene involved in the biosynthesis of amygdalin, whose reduced expression has been correlated with the sweet almond phenotype. Altogether, our results suggest a key role of TEs in the recent history and diversification of almond and its close relative peach.
Significance Statement
Almond and peach are closely related and cross‐compatible species of the genus Prunus that separated about 6 million years ago. Here we show that the almond genome, with 227.6 Mbp and 27 696 protein‐coding genes, is highly similar to that of peach. However, transposable elements have been recently active and have generated mutations that may be responsible for some key phenotypic differences between peach and almond, such as the sweet versus bitter almond taste.
Microbial fuel cells (MFCs) operating with complex microbial communities have been extensively reported in the past, and are commonly used in applications such as wastewater treatment, bioremediation ...or in-situ powering of environmental sensors. However, our knowledge on how the composition of the microbial community and the different types of electron transfer to the anode affect the performance of these bioelectrochemical systems is far from complete. To fill this gap of knowledge, we designed a set of three MFCs with different constrains limiting direct and mediated electron transfer to the anode.
The results obtained indicate that MFCs with a naked anode on which a biofilm was allowed unrestricted development (MFC-A) had the most diverse archaeal and bacterial community, and offered the best performance. In this MFC both, direct and mediated electron transfer, occurred simultaneously, but direct electron transfer was the predominant mechanism. Microbial fuel cells in which the anode was enclosed in a dialysis membrane and biofilm was not allowed to develop (MFC-D), had a much lower power output (about 60% lower), and a prevalence of dissolved redox species that acted as putative electron shuttles. In the anolyte of this MFC, Arcobacter and Methanosaeta were the prevalent bacteria and archaea respectively. In the third MFC, in which the anode had been covered by a cation selective nafion membrane (MFC-N), power output decreased a further 5% (95% less than MFC-A). In this MFC, conventional organic electron shuttles could not operate and the low power output obtained was presumably attributed to fermentation end-products produced by some of the organisms present in the anolyte, probably Pseudomonas or Methanosaeta.
Electron transfer mechanisms have an impact on the development of different microbial communities and in turn on MFC performance. Although a stable current was achieved in all cases, direct electron transfer MFC showed the best performance concluding that biofilms are the major contributors to current production in MFCs. Characterization of the complex microbial assemblages in these systems may help us to unveil new electrogenic microorganisms and improve our understanding on their role to the functioning of MFCs.
Since 1959 with the proposal of Double Agar Layer (DAL) method for phage detection and quantification, many sophisticated methods have emerged meanwhile. However, many of them are either too ...complex/expensive or insensitive to replace routine utilization of DAL method in clinical, environmental and industrial environments. For that purpose, we have explored an alternative method for the detection and quantification of bacteriophages that fulfills the criteria of being rapid, simple and inexpensive. In this paper we have developed a method based on the analysis of optical density kinetics in bacterial cultures exposed to phage-containing samples. Although the decrease in optical density caused by cell lysis was one of the first observable consequences of the effect of viral infection in bacterial cultures, the potential of the method for the assessment of phage abundance has never been fully exploited. In this work we carry out a detailed study of optical density kinetics in phage-infected bacterial cultures, as a function of both, phage abundance and initial concentration of the host organisms. In total, 90 different combinations of bacteria/phage concentrations have been used. The data obtained provide valuable information about sensitivity ranges, duration of the assay, percentages of inhibition and type of lysing behavior for each phage concentration. The method described can detect, as few as 10 phage particles per assay volume after a phage incubation period of 3.5h. The duration of the assay can be shortened to 45min at the expense of losing sensitivity and increasing the limit of detection to 108 pfu/ml. Despite using non-sophisticated technology, the method described has shown sensitivity and response time comparable to other high-end methods. The simplicity of the technology and of the analytical steps involved, make the system susceptible of miniaturization and automation for high-throughput applications which can be implemented in routine analysis in many environments.
Summary
Ethylene is a gaseous plant hormone involved in defense, adaptations to environmental stress and fruit ripening. Its relevance to the latter makes its detection highly useful for ...physiologists interested in the onset of ripening. Produced as a sharp peak during the respiratory burst, ethylene is biologically active at tens of nl L−1. Reliable quantification at such concentrations generally requires specialized instrumentation. Here we present a rapid, high‐sensitivity method for detecting ethylene in attached fruit using a conventional gas chromatography–mass spectrometry (GC‐MS) system and in situ headspace collection chambers. We apply this method to melon (Cucumis melo L.), a unique species consisting of climacteric and non‐climacteric varieties, with a high variation in the climacteric phenotype among climacteric types. Using a population of recombinant inbred lines (RILs) derived from highly climacteric (‘Védrantais’, cantalupensis type) and non‐climacteric (‘Piel de Sapo’, inodorus type) parental lines, we observed a significant variation for the intensity, onset and duration of the ethylene burst during fruit ripening. Our method does not require concentration, sampling times over 1 h or fruit harvest. We achieved a limit of detection of 0.41 ± 0.04 nl L−1 and a limit of quantification of 1.37 ± 0.13 nl L−1 with an analysis time per sample of 2.6 min. Validation of the analytical method indicated that linearity (>98%), precision (coefficient of variation ≤2%) and sensitivity compared favorably with dedicated optical sensors. This study adds to evidence of the characteristic climacteric ethylene burst as a complex trait whose intensity in our RIL population lies along a continuum in addition to two extremes.
Significance Statement
We present a rapid, non‐invasive headspace assay that detects trace emissions of ethylene in attached, developing fruit without concentration and show its utility in dissecting climacteric fruit ripening in melon using a recombinant inbred line population. The short sampling and analysis times support high throughput workflows with a sensitivity of 1 part per billion using a conventional capillary gas chromatography – mass spectrometry system, a vital technique for plant biologists studying climacteric ripening mechanisms.
Even though transgender people continue to experience violence and discrimination in many aspects of life, there has been progressive recognition of their experiences and demands in recent decades. ...This article analyses the process of claiming civil rights and the evolution of health care for transgender people in Spain, from the mid-1970s to the present day, paying particular attention to the narratives of key actors involved. To this end, three socio-historical periods are identified: (1) the travesti period (the mid-1970s to the early 1990s), characterised by strong social and institutional transphobia and resulting self-care practices; (2) the transexual period (mid-1990s to the 2000s), when demands for health care were institutionalised under a pathological medical model; and (3) the transgénero or trans period (2010s until the present) when identity and bodily autonomy have been re-claimed through a socio-cultural prism that has denounced pathologisation. At each stage, political, social and economic factors intervened at both national and international levels to trigger an ongoing negotiation between transgender movements and dominant social institutions, all within a changing universe of social values.
In recent years, local government administrations in Spain have strengthened their commitment to putting into effect policies that favour the well-being of LGBTQ+ people. This has happened not only ...in large cities, but in small rural municipalities as well. Based on the discourses, representations and practices of professionals in health and social services, this article is organised around two interrelated axes of analysis. First, we assess the extent of knowledge regarding public policies among professionals and LGBTQ+ people. And second, we examine the rural area as a specific setting for the application of LGBTQ+ policies. This leads us to the conclusion that such legal changes are important but not sufficient in themselves to ensure the well-being of LGBTQ+ people. Moreover, LGBTQ+ policies need to consider local contexts and avoid transferring the rationale of the big city into rural environments.
SUMMARY Fruit ripening is an essential developmental stage in Angiosperms triggered by hormonal signals such as ethylene, a major player in climacteric ripening. Melon is a unique crop showing both ...climacteric and non‐climacteric cultivars, offering an ideal model for dissecting the genetic mechanisms underpinning this process. The major quantitative trait locus ETHQV8.1 was previously identified as a key regulator of melon fruit ripening. Here, we narrowed down ETHQV8.1 to a precise genomic region containing a single gene, the transcription factor CmERF024 . Functional validation using CRISPR/Cas9 knock‐out plants unequivocally identified CmERF024 as the causal gene governing ETHQV8.1 . The erf024 mutants exhibited suppression of ethylene production, leading to a significant delay and attenuation of fruit ripening. Integrative multi‐omic analyses encompassing RNA‐seq, DAP‐seq, and DNase‐seq revealed the association of CmERF024 with chromatin accessibility and gene expression dynamics throughout fruit ripening. Our data suggest CmERF024 as a novel regulator of climacteric fruit ripening in melon.
Significance Statement The current study describes a novel regulator of climacteric fruit ripening in melon, ERF024 (an ethylene‐responsive transcription factor), providing new insights into this complex system. This transcription factor would act in the first stages of fruit ripening, adding a new layer to the control of this key process in plant life cycle.
En el presente artículo se analiza el modo en que se ha conceptuado la transexualidad en el Manual Diagnóstico y Estadístico de los Trastornos Mentales (DSM). Veremos que los sucesivos cambios de ...denominación y de criterios diagnósticos obedecen a las presiones recibidas por los redactores del manual por parte de científicos, académicos, organismos políticos y asociaciones por los derechos “trans”. Fruto de estas tensiones se ha reconceptualizado la transexualidad en diversas ocasiones, pero se han mantenido las connotaciones mórbidas de la categoría diagnóstica. Abordaremos asimismo el debate sobre la patologización de la transexualidad, que está dominado por dos discursos contrapuestos: el que justifica su inclusión en el DSM porque cree que de este modo se garantiza el acceso a la terapia hormonal y quirúrgica, y el que la critica porque considera que el diagnóstico contribuye a la estigmatización de las personas “trans”. Concluiremos el artículo sosteniendo que el acceso a los recursos sanitarios para personas “trans” ha de entenderse como un derecho básico que no puede estar sujeto a requisitos clínicos.
Currently, identification of pathogenic bacteria present at very low concentration requires a preliminary culture-based enrichment step. Many research efforts focus on the possibility to shorten this ...pre-enrichment step which is needed to reach the minimal number of cells that allows efficient identification. Rapid microbiological controls are a real public health issue and are required in food processing, water quality assessment or clinical pathology. Thus, the development of new methods for faster detection and isolation of pathogenic culturable bacteria is necessary. Here we describe a specific enrichment technique for culturable Gram negative bacteria, based on non-lethal click chemistry and the use of magnetic beads that allows fast detection and isolation. The assimilation and incorporation of an analog of Kdo, an essential component of lipopolysaccharides, possessing a bio-orthogonal azido function (Kdo-N3), allow functionalization of almost all Gram negative bacteria at the membrane level. Detection can be realized through strain-promoted azide-cyclooctyne cycloaddition, an example of click chemistry, which interestingly does not affect bacterial growth. Using E. coli as an example of Gram negative bacterium, we demonstrate the excellent specificity of the technique to detect culturable E. coli among bacterial mixtures also containing either dead E. coli, or live B. subtilis (as a model of microorganism not containing Kdo). Finally, in order to specifically isolate and concentrate culturable E. coli cells, we performed separation using magnetic beads in combination with click chemistry. This work highlights the efficiency of our technique to rapidly enrich and concentrate culturable Gram negative bacteria among other microorganisms that do not possess Kdo within their cell envelope.
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