Gens de superviviència bacteriana

Un nou pas en l'estudi de la genòmica permetrà entendre una mica més la vida cel·lular i molecular present als oceans. En aquest cas, l'anàlisi s'ha centrat en el bacteri Polaribacter sp. MED152, un microorganisme abundant en el mar que ha sabut sobreviure en ambients pobres en carboni en els quals no sempre pot trobar els compostos necessaris per al seu creixement. La clau està en la proteorodopsina, una proteïna que permet al bacteri obtenir energia a partir de la llum. Una estratègia de supervivència que, fins ara, era desconeguda, i que pot ser rellevant en l'estudi del paper d'aquests microorganismes en els cicles marins.Un nuevo paso en el estudio de la genómica permitirá entender un poco más la vida celular y molecular presente en los océanos. En este caso, el análisis se ha centrado en la bacteria Polaribacter sp. MED152, un microorganismo abundante en el mar que ha sabido sobrevivir en ambientes pobres en carbono, en los que no siempre encuentra los compuestos necesarios para su crecimiento. La clave está en la proteorodopsina, una proteína que lo que hace es permitir a la bacteria obtener energía a partir de la luz. Una estrategia de supervivencia que, hasta ahora, era desconocida, y que puede ser relevante en el estudio del papel de estos microorganismos en los ciclos marinos.A new advance in genomics research will allow for a better understanding of cellular and molecular life in oceans. In this case, the analysis focuses on the marine bacterium Polaribacter sp. MED152, a microorganism widely found in oceans which has survived in carbon- deficient environments and cannot always find all the compounds it needs to grow. The key lies in proteorhodopsins, proteins which allow bacteria to obtain energy from light. This survival strategy was unknown of until now and could become relevant when studying the role these microorganisms play in marine cycles

Microorganismes termofílics en biofilms de sistemes d'irrigació per degoteig en hivernacles

El reg per degoteig permet optimitzar la reutilització d'aigua i fer més eficient la irrigació, però el sistema sovint presenta problemes d'obstrucció provocats sobretot per acumulació de material d'origen biològic, que en molts casos comença per biofilms (o biopelícules) de bacteris. Un estudi dels biofilms que obturaven el sistema d'irrigació d'un hivernacle experimental a Almeria ha detectat un predomini de seqüències de microorganismes adaptats a créixer en ambients amb altes temperatures relacionades amb organismes potencialment formadors d'espores.El riego por goteo permite optimizar la reutilización de agua y hacer más eficiente la irrigación, pero el sistema a menudo presenta problemas de obstrucción provocados sobre todo por acumulación de material de origen biológico, que en muchos casos comienza por biofilms (o biopelículas) de bacterias. Un estudio de los biofilms que obturan el sistema de irrigación de un invernadero experimental en Almería ha detectado un predominio de secuencias de microorganismos adaptados a crecer en ambientes con altas temperaturas relacionadas con organismos potencialmente formadores de esporas.Drip irrigation optimises water reuse and makes irrigation more efficient, but the system often presents problems of obstruction caused mainly by the accumulation of material of biological origin, which often begins with bacterial biofilms. A study of biofilms clogging the irrigation system of an experimental greenhouse in Almeria has found a predominance of microorganism sequences adapted to growing in environments with high temperatures related to potential spore-forming organisms

Light-limited growth of Chromatium vinosum

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Endoplasmic Reticulum Stress during Mammalian Follicular Atresia

Follicles are ovarian structures that contain a single germ cell. During the mammalian reproductive lifetime, ovarian follicles mature through the process of follicular development, with the aim of selecting oocytes for ovulation. As part of this process, several follicles are eliminated by means of follicular atresia, a mechanism that mainly involves apoptosis. Nevertheless, it has been shown that there are other routes of programmed cell death in the ovary including autophagy, paraptosis, and necroptosis. Surprisingly, the endoplasmic reticulum is involved in these different programmed cell death pathways. Moreover, there are several evidences for the pathways triggered by intra- and extracellular signals in endoplasmic reticulum-induced cell death. Thus, it is important to analyze the participation of endoplasmic reticulum in follicular atresia

Biofunctionalization of cork with Moringa oleifera seeds and use of PMA staining and qPCR to detect viability of Escherichia coli

Cork matrices biofunctionalized with Moringa oleifera seed extracts (MoSe) have potential for use as a biofilter with antibacterial properties to reduce waterborne pathogens. The aim of this study was to evaluate the effect of cork biofunctionalized with active antimicrobial compounds of MoSe (f-cork) on the inhibition of Escherichia coli (InhEc). The LacZ gene from a strain of E. coli was used as the target sequence using viability quantification Polymerase Chain Reaction (qPCR) and differentiation of viable and dead bacteria through selective cell viability PMA staining. To perform this, a 27−4 fractional factorial design and a biofiltration system were used to evaluate the effect of the active protein in MoSe immobilized in granulated cork on InhEc. We found that the potential for antimicrobial activity increased with f-cork for an effective maximal bacterial reduction (99.99%; p < 0.05). The effect of f-cork functionalized with MoSe on E. coli viability was of 0.024% and 0.005% for the cells exposed to PMA, respectively, being the relevant conditions in treatment 2: (0 L/min) without aeration, (5%) MoSe and (5 mm) cork particle. In conclusion, the f-cork functionalized with MoSe presented biosorbent and antibacterial properties that effectively reduced the E. coli growth

Prevalence of potentially thermophilic microorganisms in biofilms from greenhouse-enclosed drip irrigation systems

Drip irrigation systems using reclaimed water often present clogging events of biological origin. Microbial communities in biofilms from microirrigation systems of an experimental greenhouse in Almería, SE Spain, which used two different qualities of water (treated wastewater and reclaimed water), were analyzed by denaturing gradient gel electrophoresis and subsequent sequencing of amplified 16S rRNA gene bands. The most remarkable feature of all biofilms was that regardless of water origin, sequences belonging to Firmicutes were prevalent (53.5 % of total mean band intensity) and that almost all sequences recovered had some similarity (between 80.2 and 97 %) to thermophilic microorganisms. Mainly, sequences were closely related to potentially spore-forming organisms, suggesting that microbial communities able to grow at high temperatures were selected from the microbiota present in the incoming water. These pioneer results may contribute to improve management strategies to minimize the problems associated to biofouling in irrigation systems

Mesonia oceanica sp. Nov., isolated from oceans during the tara oceans expedition, with a preference for mesopelagic waters

Strain ISS653T, isolated from Atlantic seawater, is a yellow pigmented, non-motile, Gram-reaction-negative rod-shaped bac-terium, strictly aerobic and chemoorganotrophic, slightly halophilic (1-15% NaCl) and mesophilic (4-37 °C), oxidase-and catalase-positive and proteolytic. Its major cellular fatty acids are iso-C15:0, iso-C15:0 2-OH, and iso-C17:0 3-OH; the major identified phospholipid is phosphatidylethanolamine and the major respiratory quinone is MK6. Genome size is 4.28 Mbp and DNA G+C content is 34.9 mol%. 16S rRNA gene sequence similarity places the strain among members of the family Flavobacteriaceae, with the type strains of Mesonia phycicola (93.2%), Salegentibacter mishustinae (93.1%) and Mesonia mobilis (92.9%) as closest relatives. Average amino acid identity (AAI) and average nucleotide identity (ANI) indices show highest values with M. mobilis (81% AAI; 78.9% ANI), M. phycicola (76% AAI; 76.3% ANI), Mesonia maritima (72% AAI, 74.9% ANI), Mesonia hippocampi (64% AAI, 70.8% ANI) and Mesonia algae (68% AAI; 72.2% ANI). Phylogenomic analysis using the Up-to-date-Bacterial Core Gene set (UBCG) merges strain ISS653T in a clade with species of the genus Mesonia. We conclude that strain ISS653T represents a novel species of the genus Mesonia for which we propose the name Mesonia oceanica sp. nov., and strain ISS653T (=CECT 9532T=LMG 31236T) as the type strain. A second strain of the species, ISS1889 (=CECT 30008) was isolated from Pacific Ocean seawater. Data obtained throughout the Tara oceans expedition indicate that the species is more abundant in the mesopelagic dark ocean than in the photic layer and it is more frequent in the South Pacific, Indian and North Atlantic oceans

Characterization of Actinomycetes Strains Isolated from the Intestinal Tract and Feces of the Larvae of the Longhorn Beetle Cerambyx welensii

[EN]Actinomycetes constitute a large group of Gram-positive bacteria present in different habitats. One of these habitats involves the association of these bacteria with insects. In this work, we have studied twenty-four actinomycetes strains isolated from the intestinal tract and feces from larvae of the xylophagous coleopteran Cerambyx welensii and have shown that seventeen strains present hydrolytic activity of some of the following substrates: cellulose, hemicellulose, starch and proteins. Fourteen of the isolates produce antimicrobial molecules against the Gram-positive bacteria Micrococcus luteus. Analysis of seven strains led us to identify the production of a wide number of compounds including streptanoate, alpiniamide A, alteramides A and B, coproporphyrin III, deferoxamine, demethylenenocardamine, dihydropicromycin, nocardamine, picromycin, surugamides A, B, C, D and E, tirandamycins A and B, and valinomycin. A significant number of other compounds, whose molecular formulae are not included in the Dictionary of Natural Products (DNP), were also present in the extracts analyzed, which opens up the possibility of identifying new active antibiotics. Molecular identification of ten of the isolated bacteria determined that six of them belong to the genus Streptomyces, two of them are included in the genus Amycolatopsis and two in the genus Nocardiopsis

El efecto del capital social en la violencia en la pareja adolescente desde una perspectiva de interseccionalidad

Antecedentes: La violencia de pareja (VP) es un fenómeno social complejo ampliamente estudiado. Sin embargo, pocos de estos estudios consideran el capital social y la interseccionalidad. Nuestro objetivo fue describir el efecto del capital social en la victimización por VP entre estudiantes de secundaria, considerando tres factores de interseccionalidad (sexo asignado al nacer, orientación sexual y origen migratorio) en dos ciudades de España en 2019-2020. Métodos: Se analizó una muestra transversal de 640 adolescentes con pareja, de 13 a 16 años, de un programa de promoción de relaciones equitativas en Alicante y Terrassa. La variable resultado fue haber sufrido violencia en la pareja (control, miedo, física o sexual) en algún momento de la vida. Se utilizaron variables individuales y relacionales para calcular la razón de prevalencia ajustada (RPa) a partir de modelos multivariable construidos mediante regresión robusta de Poisson, y estratificados por sexo, orientación sexual y origen migratorio. Resultados: La mayor prevalencia de VP (56,25%) se encontró en adolescentes lesbianas, gays o bisexuales (LGB) sin actividad social. La orientación LGB se asoció significativamente con la victimización por VP en los adolescentes con origen en países de bajos ingresos (PBI) (aPR: 1,93) y en las chicas (aPR: 1,53). Por último, la procedencia de un PBI fue un determinante significativo de la VP en los chicos (aPR: 1,76) y en los estudiantes, independientemente de la orientación sexual. Una mayor actividad social mostró un efecto protector para los estudiantes de origen en países de altos ingresos (PAI) y de orientación sexual LGB, independientemente del sexo y la orientación sexual. Conclusiones: La actividad social se asocia de forma desigual con una menor victimización por violencia de la pareja en algún momento de la vida adolescente. La fuerte asociación del origen migratorio y la orientación sexual con la VPI refuerza el enfoque de su prevención en los adolescentes desde una perspectiva de interseccionalidad.Background: Intimate partner violence (IPV) is a complex social phenomenon widely studied. However, few of these studies consider social capital and intersectionality. Our aim was to describe the effect of social capital in IPV victimisation among secondary students, considering three factors of intersectionality (sex assigned at birth, sexual orientation and migration background) in two cities of Spain in 2019-2020. Methods: We analysed a cross-sectional sample of 640 ever-partnered adolescents aged 13–16 years who had taken part in a programme for positive relationship. The main outcome was lifetime IPV (control, fear, physical or sexual violence). Individual and relational variables (bonding social capital) were used to calculate adjusted prevalence ratios (aPR) from multivariate Robust Poisson regression models stratified by sex assigned at birth, sexual orientation and migration background (factors of intersectionality). Results: The highest IPV prevalence (56.25%) was found in lesbian, gay or bisexual (LGB) adolescents without social activity. LGB orientation was significantly associated with IPV victimisation in adolescents with low-income country (LIC) backgrounds (aPR: 1.93) and in girls (1.53). Finally, a LIC background was a significant determinant of IPV in boys (aPR: 1.76) and in students independently of sexual orientation. Higher social activity showed a protective effect for students with HIC backgrounds and LGB-sexual orientations. A possible protective effect of social support in HIC backgrounds and regardless of sex and sexual orientation must be considered. Conclusions: Social activity is unequally associated with less lifetime IPV. The strong association of migration background and sexual orientation with IPV reinforces the approach to its prevention in adolescents from an intersectionality perspective.This study was funded by the multi-centre project "Promotion of protective assets against gender violence in adolescence and preadolescence" (Grant reference PI18/00590 and PI18/00544) of the Carlos III Institute of Health, as an intermediary body of the European Regional Development Fund (ERDF) and the European Social Fund (ESF). The project was also supported by the Centro de Investigación Biomédica en Red de Epidemiología Salud Pública (CIBERESP) through the subprogramme on Prevention of Gender Violence of the Programme on Social Determinants of Health (no grant award number specified)