Digital multiplex ligation assay for highly multiplexed screening of beta-lactamase-encoding genes in bacterial isolates

Increasing incidence of antibiotic resistance in clinical and environmental settings calls for increased scalability in their surveillance. Current screening technologies are limited by the number of samples and genes that can easily be screened. We demonstrate here digital multiplex ligation assay (dMLA) as a low-cost targeted genomic detection workflow capable of highly-parallel screening of bacterial isolates for multiple target gene regions simultaneously. Here, dMLA is used for simultaneous detection of 1187 beta-lactamase-encoding genes, including extended spectrum beta-lactamase (ESBL) genes, in 74 bacterial isolates. We demonstrate dMLA as a light-weight and cost-efficient workflow which provides a highly scalable tool for antimicrobial resistance surveillance and is also adaptable to genetic screening applications beyond antibiotic resistance.Tamminen et al. develop a digital multiplex ligation assay (dMLA) that enables the detection of bacterial isolates using probe hybridization and ligation-based assays with next-generation sequencing. Their method can be applied in high-throughput and affordable screening for antibiotic resistance

Phylogenomic analysis sheds light on the evolutionary pathways towards acoustic communication in Orthoptera

Acoustic communication is enabled by the evolution of specialised hearing and sound producing organs. In this study, we performed a large-scale macroevolutionary study to understand how both hearing and sound production evolved and affected diversification in the insect order Orthoptera, which includes many familiar singing insects, such as crickets, katydids, and grasshoppers. Using phylogenomic data, we firmly establish phylogenetic relationships among the major lineages and divergence time estimates within Orthoptera, as well as the lineage-specific and dynamic patterns of evolution for hearing and sound producing organs. In the suborder Ensifera, we infer that forewing-based stridulation and tibial tympanal ears co-evolved, but in the suborder Caelifera, abdominal tympanal ears first evolved in a non-sexual context, and later co-opted for sexual signalling when sound producing organs evolved. However, we find little evidence that the evolution of hearing and sound producing organs increased diversification rates in those lineages with known acoustic communication

Climate change goes underground: effects of elevated atmospheric CO2 on microbial community structure and activities in the rhizosphere.

General concern about climate change has led to growing interest in the responses of terrestrial ecosystems to elevated concentrations of CO2 in the atmosphere. Experimentation during the last two to three decades using a large variety of approaches has provided sufficient information to conclude that enrichment of atmospheric CO2 may have severe impact on terrestrial ecosystems. This impact is mainly due to the changes in the organic C dynamics as a result of the effects of elevated CO2 on the primary source of organic C in soil, i.e., plant photosynthesis. As the majority of life in soil is heterotrophic and dependent on the input of plant-derived organic C, the activity and functioning of soil organisms will greatly be influenced by changes in the atmospheric CO2 concentration. In this review, we examine the current state of the art with respect to effects of elevated atmospheric CO2 on soil microbial communities, with a focus on microbial community structure. On the basis of the existing information, we conclude that the main effects of elevated atmospheric CO2 on soil microbiota occur via plant metabolism and root secretion, especially in C3 plants, thereby directly affecting the mycorrhizal, bacterial, and fungal communities in the close vicinity of the root. There is little or no direct effect on the microbial community of the bulk soil. In particular, we have explored the impact of these changes on rhizosphere interactions and ecosystem processes, including food web interactions

Análisis del posible acuerdo de asociación entre la Unión Europea y Centroamérica: Caso concreto de Costa Rica y del tema de solución de controversias

Tesis para optar por el grado de Licenciatura en Derecho de la Universidad de Costa RicaCentroamérica y la Unión Europea se encuentran actualmente en negociaciones en aras de llegar a un Acuerdo de Asociación, cuyo nombre viene de la forma en que la Unión Europea ha decidido enfocar sus negociaciones, ya que, además de contener un componente comercial típico, incluye también el diálogo político en temas como terrorismo y desarme, crímenes de lesa humanidad, democracia, derechos humanos y desarrollo humano sostenible y la cooperación en dos ejes la integración regional y la cohesión social (educación, salud, fortalecimiento de PYMES, cultura, entre otros factores).El presente trabajo analiza, en primer lugar, la situación de nuestro país y Centroamérica, así como el escenario Europeo para percatarse de las asimetrías existentes, sobre todo en el tema de integración de ambas regiones, ya que la Unión Europea cuenta con una estructura plenamente firme y definida, mientras que Centroamérica carece de ésta, lo que dificulta un poco el panorama para la Parte centroamericana, por ser un requisito la integración de la región. Posteriormente, se analiza lo que se conoce hasta el momento del Acuerdo de Asociación y sus diversos elementos, como son: los antecedentes, los intereses, la posible estructura, las rondas de negociación y la posición oficial de Costa Rica. En el transcurso de las negociaciones que se han realizado se denota una concertación de la región centroamericana. Finalmente, se estudia el tema de solución de controversias, viendo como éste se ha tratado en diferentes escenarios como la Organización Mundial del Comercio, el Mecanismo centroamericano y como lo ha hecho la Unión Europea en Acuerdos de este tipo con países como Chile y México, sabiendo de antemano que la situación que se expone es complicada por cuanto sería el primer Acuerdo que la Unión Europea suscriba de Región a Región.UCR::Vicerrectoría de Docencia::Ciencias Sociales::Facultad de Derech

Enterococcus faecium PBP5-S/R, the missing link between PBP5-S and PBP5-R.

Abstract During a study to investigate the evolution of ampicillin resistance in Enterococcus faecium, we observed that a number of E. faecium strains, mainly from the recently described subclade A2, showed PBP5 sequences in between PBP5-S and PBP5-R. These hybrid PBP5-S/R patterns reveal a progression of amino acid changes from the S form to the R form of this protein; however, these changes do not strictly correlate with changes in ampicillin MICs