Metaproteomic and gene expression analysis of interspecies interactions in a PAH-degrading synthetic microbial consortium constructed with the key microbes of a natural consortium.

Polycyclic Aromatic Hydrocarbons (PAHs) impose adverse effects on the environment and human life. The use of synthetic microbial consortia is promising in bioremediation of contaminated sites with these pollutants. However, the design of consortia taking advantage of natural interactions has been poorly explored. In this study, a dual synthetic bacterial consortium (DSC_AB) was constructed with two key members (Sphingobium sp. AM and Burkholderia sp. Bk), of a natural PAH degrading consortium. DSC_AB showed significantly enhanced degradation of PAHs and toxic intermediary metabolites relative to the axenic cultures, indicating the existence of synergistic relationships. Metaproteomic and gene-expression analyses were applied to obtain a view of bacterial performance during phenanthrene removal. Overexpression of the Bk genes, naph, biph, tol and sal and the AM gene, ahdB, in DSC_AB relative to axenic cultures, demonstrated that both strains are actively participating in degradation, which gave evidence of cross-feeding. Several proteins related to stress response were under-expressed in DSC_AB relative to axenic cultures, indicating that the division of labour reduces cellular stress, increasing the efficiency of degradation. This is the one of the first works revealing bacterial relationships during PAH removal in a synthetic consortium applying an omics approach. Our findings could be used to develop criteria for evaluating the potential effectiveness of synthetic bacterial consortia in bioremediation.

DNA stable isotope probing reveals the impact of trophic interactions on bioaugmentation of soils with different pollution histories.

BACKGROUND: Bioaugmentation is considered a sustainable and cost-effective methodology to recover contaminated environments, but its outcome is highly variable. Predation is a key top-down control mechanism affecting inoculum establishment, however, its effects on this process have received little attention. This study focused on the impact of trophic interactions on bioaugmentation success in two soils with different pollution exposure histories. We inoculated a 13C-labelled pollutant-degrading consortium in these soils and tracked the fate of the labelled biomass through stable isotope probing (SIP) of DNA. We identified active bacterial and eukaryotic inoculum-biomass consumers through amplicon sequencing of 16S rRNA and 18S rRNA genes coupled to a novel enrichment factor calculation. RESULTS: Inoculation effectively increased PAH removal in the short-term, but not in the long-term polluted soil. A decrease in the relative abundance of the inoculated genera was observed already on day 15 in the long-term polluted soil, while growth of these genera was observed in the short-term polluted soil, indicating establishment of the inoculum. In both soils, eukaryotic genera dominated as early incorporators of 13C-labelled biomass, while bacteria incorporated the labelled biomass at the end of the incubation period, probably through cross-feeding. We also found different successional patterns between the two soils. In the short-term polluted soil, Cercozoa and Fungi genera predominated as early incorporators, whereas Ciliophora, Ochrophyta and Amoebozoa were the predominant genera in the long-term polluted soil. CONCLUSION: Our results showed differences in the inoculum establishment and predator community responses, affecting bioaugmentation efficiency. This highlights the need to further study predation effects on inoculum survival to increase the applicability of inoculation-based technologies. Video Abstract.

Datathons: fostering equitability in data reuse in ecology.

Approaches to rapidly collecting global biodiversity data are increasingly important, but biodiversity blind spots persist. We organized a three-day Datathon event to improve the openness of local biodiversity data and facilitate data reuse by local researchers. The first Datathon, organized among microbial ecologists in Uruguay and Argentina assembled the largest microbiome dataset in the region to date and formed collaborative consortia for microbiome data synthesis.

Design and evaluation of synthetic bacterial consortia for optimized phenanthrene degradation through the integration of genomics and shotgun proteomics.

Two synthetic bacterial consortia (SC) composed of bacterial strains Sphingobium sp. (AM), Klebsiella aerogenes (B), Pseudomonas sp. (Bc-h and T), Burkholderia sp. (Bk) and Inquilinus limosus (Inq) isolated from a natural phenanthrene (PHN)-degrading consortium (CON) were developed and evaluated as an alternative approach to PHN biodegradation in bioremediation processes. A metabolic network showing the potential role of strains was reconstructed by in silico study of the six genomes and classification of dioxygenase enzymes using RHObase and AromaDeg databases. Network analysis suggested that AM and Bk were responsible for PHN initial attack, while Inq, B, T and Bc-h would degrade PHN metabolites. The predicted roles were further confirmed by physiological, RT-qPCR and metaproteomic assays. SC-1 with AM as the sole PHN degrader was the most efficient. The ecological roles inferred in this study can be applied to optimize the design of bacterial consortia and tackle the biodegradation of complex environmental pollutants.

Endocorona, un enfoque diferente en rehabilitación oral

RESUMEN Introducción: Con el avance de la tecnología adhesiva, nuevas técnicas y materiales restauradores están siendo utilizados para el tratamiento de dientes endodonciados, por ello, las endocoronas son una alternativa clínica para su tratamiento. La ventaja de esta restauración es que tiene mejores características macro retentivas, requiere menor tiempo clínico y de laboratorio. Objetivo: Proporcionar información bibliográfica actual sobre esta nueva alternativa para aplicar una nueva guía en rehabilitación oral con el uso de la endocorona mediante una revisión de la literatura. Método: Se realizó una revisión bibliográfica detallada, con la consideración de artículos originales o casos clínicos que incluían información relacionada a las restauraciones de tipo endocorona. La búsqueda se efectuó en las bases de datos PubMed, SciELO, Science Direct, Elsevier y Google Académico. Resultados: Las restauraciones de tipo endocorona son un monobloque único que devuelve la anatomía completa de la corona dental, la cual aprovecha la cámara pulpar para así lograr una mayor adhesión y macro retención mecánica. Este enfoque restaurador proporciona una función adecuada y estética, así como la integridad biomecánica de las estructuras no vitales. Conclusiones: Actualmente en la Odontología moderna se emplea el término de mínima intervención, conservando en su mayor cantidad posible el tejido dental de manera que los dientes tengan mayor funcionalidad, por ello las endocoronas son una opción segura y con buen pronóstico a largo plazo en rehabilitación oral para tratar piezas endodonciadas, debido a que es un procedimiento técnicamente más conservador, estético, sencillo y de menor costo.

ABSTRACT Introduction: With the advancement of adhesive technology, new techniques and restorative materials are being used for the treatment of root canals; therefore endocrowns are a clinical alternative for their treatment. The advantage of this restoration is that it has better macro retentive characteristics, requires less clinical and laboratory time. Objective: To provide current bibliographic information on this new alternative to apply a new guide in oral rehabilitation with the use of endocrown through a literature review. Method: A detailed bibliographic review was carried out, with the consideration of original articles or clinical cases that included information related to endocrown-type restorations. The search was carried out in the databases PubMed, SciELO, Science Direct, Elsevier and Google Scholar. Results: Endocrown restorations are a single monoblock that rebuilds the complete anatomy of the dental crown, which takes advantage of the pulp chamber to achieve greater adhesion and macro mechanical retention. This restorative approach provides adequate function and aesthetics, as well as the biomechanical integrity of non-vital structures. Conclusions: The term minimal intervention is currently very used in modern dentistry, preserving the dental tissue as much as possible so that the teeth have greater functionality. Endocrowns are a safe option with a good long-term prognosis in oral rehabilitation to treat root canals, because it is a technically more conservative, aesthetic, simple and lower-cost procedure.

RESUMO Introdução: Com o avanço da tecnologia adesiva, novas técnicas e materiais restauradores estão sendo utilizados para o tratamento de dentes endodônticos, portanto os endocrowns são uma alternativa clínica para seu tratamento. A vantagem dessa restauração é que ela apresenta melhores características macro retentivas, requer menos tempo clínico e laboratorial. Objetivo: Fornecer informações bibliográficas atuais sobre esta nova alternativa de aplicação de um novo guia na reabilitação oral com o uso de endocrown por meio de uma revisão da literatura. Método: Foi realizada uma revisão bibliográfica detalhada, considerando artigos originais ou casos clínicos que incluíam informações relacionadas a restaurações do tipo endocrown. A busca foi realizada nas bases de dados PubMed, SciELO, Science Direct, Elsevier e Google Scholar. Resultados: As restaurações do tipo endocrown são um único monobloco que devolve a anatomia completa da coroa dentária, que aproveita a câmara pulpar para obter maior adesão e retenção macromecânica. Esta abordagem restauradora fornece função e estética adequadas, bem como a integridade biomecânica de estruturas não vitais. Conclusões: Atualmente na odontologia moderna é utilizado o termo de intervenção mínima, preservando-se o tecido dentário o máximo possível para que os dentes tenham maior funcionalidade, portanto endocrowns são uma opção segura e com bom prognóstico em longo prazo na reabilitação oral para tratamento da endodontia dentes, por ser um procedimento tecnicamente mais conservador, estético, simples e de menor custo.