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1.
Artículo en Inglés | MEDLINE | ID: mdl-36674160

RESUMEN

In recent years, smart city projects and initiatives have surged around the globe. Yet, a wide range of factors determine the success or failure of such initiatives and there is still a long road ahead in terms of effective governance and innovation management. In such a context, this study explores the specific case of PCT Cartuja (science and technology park in Seville, Spain)-analyzing several smart-mobility and smart-climate solutions from a Triple Helix Model standpoint. The authors tap into multiple information sources to describe the case and key implications of smart initiatives for both theory and management are discussed. This paper shows the current progress as well as the remaining challenges to illustrate how public-private partnerships and conflict can be effectively managed.


Asunto(s)
Clima , Tecnología , España , Ciudades
2.
Nucleic Acids Res ; 50(6): 3432-3444, 2022 04 08.
Artículo en Inglés | MEDLINE | ID: mdl-35234892

RESUMEN

DNA helicases of the RecD2 family are ubiquitous. Bacillus subtilis RecD2 in association with the single-stranded binding protein SsbA may contribute to replication fork progression, but its detailed action remains unknown. In this work, we explore the role of RecD2 during DNA replication and its interaction with the RecA recombinase. RecD2 inhibits replication restart, but this effect is not observed in the absence of SsbA. RecD2 slightly affects replication elongation. RecA inhibits leading and lagging strand synthesis, and RecD2, which physically interacts with RecA, counteracts this negative effect. In vivo results show that recD2 inactivation promotes RecA-ssDNA accumulation at low mitomycin C levels, and that RecA threads persist for a longer time after induction of DNA damage. In vitro, RecD2 modulates RecA-mediated DNA strand-exchange and catalyzes branch migration. These findings contribute to our understanding of how RecD2 may contribute to overcome a replicative stress, removing RecA from the ssDNA and, thus, it may act as a negative modulator of RecA filament growth.


Asunto(s)
Proteínas Bacterianas , Rec A Recombinasas , Bacillus subtilis/genética , Bacillus subtilis/metabolismo , Proteínas Bacterianas/metabolismo , ADN Helicasas/genética , ADN Helicasas/metabolismo , ADN de Cadena Simple/metabolismo , Rec A Recombinasas/metabolismo
3.
Proc Natl Acad Sci U S A ; 118(28)2021 07 13.
Artículo en Inglés | MEDLINE | ID: mdl-34244425

RESUMEN

Virus infection causes major rearrangements in the subcellular architecture of eukaryotes, but its impact in prokaryotic cells was much less characterized. Here, we show that infection of the bacterium Bacillus subtilis by bacteriophage SPP1 leads to a hijacking of host replication proteins to assemble hybrid viral-bacterial replisomes for SPP1 genome replication. Their biosynthetic activity doubles the cell total DNA content within 15 min. Replisomes operate at several independent locations within a single viral DNA focus positioned asymmetrically in the cell. This large nucleoprotein complex is a self-contained compartment whose boundaries are delimited neither by a membrane nor by a protein cage. Later during infection, SPP1 procapsids localize at the periphery of the viral DNA compartment for genome packaging. The resulting DNA-filled capsids do not remain associated to the DNA transactions compartment. They bind to phage tails to build infectious particles that are stored in warehouse compartments spatially independent from the viral DNA. Free SPP1 structural proteins are recruited to the dynamic phage-induced compartments following an order that recapitulates the viral particle assembly pathway. These findings show that bacteriophages restructure the crowded host cytoplasm to confine at different cellular locations the sequential processes that are essential for their multiplication.


Asunto(s)
Bacillus subtilis/virología , Compartimento Celular , Virosis/patología , Bacillus subtilis/ultraestructura , Bacteriófagos/fisiología , Bacteriófagos/ultraestructura , Cápside/metabolismo , Replicación del ADN , ADN Viral/biosíntesis , ADN Polimerasa Dirigida por ADN , Interacciones Huésped-Patógeno , Complejos Multienzimáticos , Factores de Tiempo , Virión/metabolismo
4.
Nucleic Acids Res ; 46(14): 7206-7220, 2018 08 21.
Artículo en Inglés | MEDLINE | ID: mdl-29947798

RESUMEN

The ubiquitous RarA/Mgs1/WRNIP protein plays a crucial, but poorly understood role in genome maintenance. We show that Bacillus subtilis RarA, in the apo form, preferentially binds single-stranded (ss) over double-stranded (ds) DNA. SsbA bound to ssDNA loads RarA, and for such recruitment the amphipathic C-terminal domain of SsbA is required. RarA is a DNA-dependent ATPase strongly stimulated by ssDNA-dsDNA junctions and SsbA, or by dsDNA ends. RarA, which may interact with PriA, does not stimulate PriA DNA unwinding. In a reconstituted PriA-dependent DNA replication system, RarA inhibited initiation, but not chain elongation. The RarA effect was not observed in the absence of SsbA, or when the host-encoded preprimosome and the DNA helicase are replaced by proteins from the SPP1 phage with similar function. We propose that RarA assembles at blocked forks to maintain genome integrity. Through its interaction with SsbA and with a preprimosomal component, RarA might impede the assembly of the replicative helicase, to prevent that recombination intermediates contribute to pathological DNA replication restart.


Asunto(s)
Adenosina Trifosfatasas/genética , Bacillus subtilis/genética , Proteínas Bacterianas/genética , Replicación del ADN/genética , Proteínas de Unión al ADN/genética , Adenosina Trifosfatasas/química , Adenosina Trifosfatasas/metabolismo , Bacillus subtilis/metabolismo , Proteínas Bacterianas/química , Proteínas Bacterianas/metabolismo , ADN/química , ADN/genética , ADN/metabolismo , ADN Helicasas/genética , ADN Helicasas/metabolismo , ADN Bacteriano/química , ADN Bacteriano/genética , ADN Bacteriano/metabolismo , ADN de Cadena Simple/química , ADN de Cadena Simple/genética , ADN de Cadena Simple/metabolismo , Proteínas de Unión al ADN/química , Proteínas de Unión al ADN/metabolismo , Genoma Bacteriano/genética , Modelos Moleculares , Conformación de Ácido Nucleico , Unión Proteica , Dominios Proteicos , Especificidad por Sustrato
5.
Front Microbiol ; 8: 1816, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29018417

RESUMEN

Natural transformation and viral-mediated transduction are the main avenues of horizontal gene transfer in Firmicutes. Bacillus subtilis SPP1 is a generalized transducing bacteriophage. Using this lytic phage as a model, we have analyzed how viral replication and recombination systems contribute to the transfer of plasmid-borne antibiotic resistances. Phage SPP1 DNA replication relies on essential phage-encoded replisome organizer (G38P), helicase loader (G39P), hexameric replicative helicase (G40P), recombinase (G35P) and in less extent on the partially dispensable 5'→3' exonuclease (G34.1P), the single-stranded DNA binding protein (G36P) and the Holliday junction resolvase (G44P). Correspondingly, the accumulation of linear concatemeric plasmid DNA, and the formation of transducing particles were blocked in the absence of G35P, G38P, G39P, and G40P, greatly reduced in the G34.1P, G36P mutants, and slightly reduced in G44P mutants. In contrast, establishment of injected linear plasmid DNA in the recipient host was independent of viral-encoded functions. DNA homology between SPP1 and the plasmid, rather than a viral packaging signal, enhanced the accumulation of packagable plasmid DNA. The transfer efficiency was also dependent on plasmid copy number, and rolling-circle plasmids were encapsidated at higher frequencies than theta-type replicating plasmids.

6.
Nucleic Acids Res ; 45(11): 6507-6519, 2017 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-28475766

RESUMEN

DNA-single strand annealing proteins (SSAPs) are recombinases frequently encoded in the genome of many bacteriophages. As SSAPs can promote homologous recombination among DNA substrates with an important degree of divergence, these enzymes are involved both in DNA repair and in the generation of phage mosaicisms. Here, analysing Sak and Sak4 as representatives of two different families of SSAPs present in phages infecting the clinically relevant bacterium Staphylococcus aureus, we demonstrate for the first time that these enzymes are absolutely required for phage reproduction. Deletion of the genes encoding these enzymes significantly reduced phage replication and the generation of infectious particles. Complementation studies revealed that these enzymes are required both in the donor (after prophage induction) and in the recipient strain (for infection). Moreover, our results indicated that to perform their function SSAPs require the activity of their cognate single strand binding (Ssb) proteins. Mutational studies demonstrated that the Ssb proteins are also required for phage replication, both in the donor and recipient strain. In summary, our results expand the functions attributed to the Sak and Sak4 proteins, and demonstrate that both SSAPs and Ssb proteins are essential for the life cycle of temperate staphylococcal phages.


Asunto(s)
Bacteriófagos/fisiología , Recombinasas/fisiología , Staphylococcus aureus/virología , Proteínas Virales/fisiología , Replicación Viral , Replicación del ADN , Proteínas de Unión al ADN/fisiología , Mutación
7.
Rev. Rol enferm ; 39(3): 196-202, mar. 2016. graf
Artículo en Español | IBECS | ID: ibc-150475

RESUMEN

Introducción. Existen diversas intervenciones de enfermería para reducir el dolor y la ansiedad tras la cirugía, entre las que destacan: relajación sistemática, música, técnicas de distracción o aplicación de calor. Objetivos. Verificar si determinadas intervenciones enfermeras intraoperatorias disminuyen el dolor y la ansiedad posteriormente. Metodología. Estudio experimental de 129 pacientes sometidos a tres tipos de cirugía (prótesis total, parcial y osteosíntesis de cadera). La muestra se dividió en dos grupos: experimental (64 pacientes, a quienes se aplicó la intervención enfermera) y control (65 pacientes). La valoración de la ansiedad se llevó a cabo mediante el State- Trait Anxiety Inventory (STAI) y la del dolor con la Escala Numérica Verbal (ENV) y el consumo de analgésicos. Se realizó un análisis estadístico comparativo utilizando el programa SPSS. Resultados. Se encontraron diferencias estadísticamente significativas intergrupos en el nivel de ansiedad-estado tras la cirugía a favor del grupo experimental (p = 0.007). Respecto al dolor, se evidenció una tendencia decreciente en ambos grupos sin que las diferencias se revelaran significativas. Los menores de 70 años presentaban menor ansiedad-estado tras la operación. La prótesis total de cadera generaba menor ansiedad que las otras operaciones. Conclusiones. La intervención enfermera mostró su utilidad en la reducción de la ansiedad, pero no en la mejoría del dolor. Mientras que en el dolor crónico la ansiedad y la percepción dolorosa se reforzarían mutuamente, en el dolor quirúrgico agudo este vínculo sería más débil, lo cual explicaría los resultados obtenidos. No obstante, se precisan más estudios al respecto (AU)


Introduction. Diverse nursing interventions have been used to relief postoperative pain and anxiety, for instance: systematic relaxation, preoperative teaching visit, music, distraction techniques or warming methods. Aim. To verify if certain nursing interventions during surgery relief postoperative pain and anxiety. Methodology. Experimental study with 129 patients under three types of surgery (total and partial hip replacement and hip osteosynthesis). The sample was divided in two groups: experimental group (64 patients, who received the nursing interventions) and control group (65 patients). The State-Trait Anxiety Inventory (STAI) and the Numerical Verbal Scale (NVS) were used to measure postoperative anxiety and pain respectively. Analgesic drug administration was also registered. A comparative statistical analysis was carried out through SPSS computerized program. Results. Statistically significant differences between both groups ere found in state anxiety after surgery in favor of experimental group (P = 0,007). Postoperative pain reflected a decreasingly tendency in both groups but differences were not statistically significant. Patients younger than 70 years old suffered less state anxiety after surgery. Total hip replacement generated less anxiety than the other two operations. Conclusions. Nursing interventions showed effectiveness in postoperative anxiety amelioration but not in pain relief. While anxiety and chronic pain would mutually reinforce, in postoperative acute pain this link may be a weaker one; hypothesis that could explain the obtained results. However, new investigations re needed (AU)


Asunto(s)
Humanos , Masculino , Femenino , Música/psicología , Musicoterapia , Musicoterapia/métodos , Atención de Enfermería/normas , Atención de Enfermería , Periodo Perioperatorio/enfermería , Manejo del Dolor/enfermería , Relajación , Terapia por Relajación/métodos , Fijación Interna de Fracturas/enfermería , Fijación Intramedular de Fracturas/enfermería , Ansiedad/enfermería , Terapia por Relajación/normas , Terapia por Relajación/tendencias , Terapia por Relajación
8.
J Virol ; 88(19): 11304-14, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25056898

RESUMEN

UNLABELLED: Although adenoviruses (AdVs) have been found in a wide variety of reptiles, including numerous squamate species, turtles, and crocodiles, the number of reptilian adenovirus isolates is still scarce. The only fully sequenced reptilian adenovirus, snake adenovirus 1 (SnAdV-1), belongs to the Atadenovirus genus. Recently, two new atadenoviruses were isolated from a captive Gila monster (Heloderma suspectum) and Mexican beaded lizards (Heloderma horridum). Here we report the full genomic and proteomic characterization of the latter, designated lizard adenovirus 2 (LAdV-2). The double-stranded DNA (dsDNA) genome of LAdV-2 is 32,965 bp long, with an average G+C content of 44.16%. The overall arrangement and gene content of the LAdV-2 genome were largely concordant with those in other atadenoviruses, except for four novel open reading frames (ORFs) at the right end of the genome. Phylogeny reconstructions and plesiomorphic traits shared with SnAdV-1 further supported the assignment of LAdV-2 to the Atadenovirus genus. Surprisingly, two fiber genes were found for the first time in an atadenovirus. After optimizing the production of LAdV-2 in cell culture, we determined the protein compositions of the virions. The two fiber genes produce two fiber proteins of different sizes that are incorporated into the viral particles. Interestingly, the two different fiber proteins assemble as either one short or three long fiber projections per vertex. Stoichiometry estimations indicate that the long fiber triplet is present at only one or two vertices per virion. Neither triple fibers nor a mixed number of fibers per vertex had previously been reported for adenoviruses or any other virus. IMPORTANCE: Here we show that a lizard adenovirus, LAdV-2, has a penton architecture never observed before. LAdV-2 expresses two fiber proteins-one short and one long. In the virion, most vertices have one short fiber, but a few of them have three long fibers attached to the same penton base. This observation raises new intriguing questions on virus structure. How can the triple fiber attach to a pentameric vertex? What determines the number and location of each vertex type in the icosahedral particle? Since fibers are responsible for primary attachment to the host, this novel architecture also suggests a novel mode of cell entry for LAdV-2. Adenoviruses have a recognized potential in nanobiomedicine, but only a few of the more than 200 types found so far in nature have been characterized in detail. Exploring the taxonomic wealth of adenoviruses should improve our chances to successfully use them as therapeutic tools.


Asunto(s)
Atadenovirus/genética , Proteínas de la Cápside/genética , ADN Viral/genética , Genoma Viral , Lagartos/virología , Virión/genética , Secuencia de Aminoácidos , Animales , Atadenovirus/clasificación , Atadenovirus/ultraestructura , Composición de Base , Secuencia de Bases , Proteínas de la Cápside/ultraestructura , ADN/genética , Expresión Génica , Datos de Secuencia Molecular , Sistemas de Lectura Abierta , Filogenia , Virión/ultraestructura
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