Paraclostridium is the Main Genus of Anaerobic Bacteria Isolated from New Species of the Marine Sponge Plakina in the Brazilian Southeast Coast.

Despite the broad assessment of sponge bacterial diversity through cultivation-independent and dependent strategies, the knowledge focusing on cultivable anaerobes from this holobiont is still incipient. Plakina is a genus with the highest number of described species from the smallest of poriferan classes, Homoscleromorpha. The Brazilian Atlantic coast has been presenting itself as a hotspot for the discovery of new plakinidae species, with initial surveys just now concerning to characterize their microbiome. The current study aimed to isolate and identify strict anaerobes from recently described species of Plakina collected at the coast of Cabo Frio, RJ. Samples of four sympatric morphotypes of Plakina cyanorosea and Plakina cabofriense were collected on the coast of Cabo Frio, RJ. Using five different culture media, a total of 93 bacterial isolates were recovered, among which 60 were strict anaerobes and, ultimately, 34 remaining viable. A total of 76.5% from these strains were mostly identified as Clostridium bifermentans by mass spectrometry and 82.4% identified by 16S rRNA sequencing, almost all of them affiliated to the genus Paraclostridium, and with one isolate identified as Clostridium butyricum by both techniques. None of the anaerobic bacteria exhibited antimicrobial activity by the adopted screening test. The present work highlights not only the need for cultivation and characterization of the anaerobic microbiota from marine sponges but also adds the existing scarce knowledge of culturable bacterial communities from Homoscleromorph sponges from Brazilian coast.

Epidemiología de bacterias anaerobias aisladas en muestras clínicas en el hospital san juan de dios, San José, Costa Rica, durante el trienio 2014, 2015 y 2016 / Epidemiology of anaerobic bacteria isolated in clinical samples at San Juan de Dios Hospital, San José, Costa Rica, during the 2014, 2015 and 2016 triennium

Resumen La epidemiología de las posibles poblaciones en riesgo de sufrir una infección por bacterias anaerobias a nivel nacional es desconocida, se debería de incentivar el conocimiento en los servicios de salud sobre este tipo de infecciones. Las bacterias anaerobias están relacionadas en los medios hospitalarios como causa importante de morbilidad, razón por la cual es conveniente conocer la epidemiologia y prevalecía de especies involucradas. En el Laboratorio de Bacteriología del Hospital San Juan de Dios, durante tres años, se analizaron un total de 1545 pacientes sospechosos de microorganismos anaerobios en medios prerreducidos, mediante un tamizaje se redujeron a un total de 469 posibles muestras, las cuales, fueron enviadas al Laboratorio de Investigación en Bacteriología Anaerobia (LIBA) para su correspondiente identificación. A lo largo de las semanas epidemiológicas de los tres años se encontraron en promedio de 1.77 casos confirmados / semana, con razón de sexo positiva a favor de los masculinos. Se determinó que solo 245 de las muestras enviadas presentaban uno o varios microorganismos anaerobios estrictos representando un 15.85% del total, identificándose 39 especies diferentes, en 306 cepas aisladas. Las mayormente importante fue el género Bacteriodes, provenientes de cavidad abdominal seguido de abscesos y heridas de piel. El presente estudio tiene como objetivo presentar datos que respalden la importancia clínica de la búsqueda de microorganismos anaerobios y que ayuden a los analistas de bacteriología a guiar cuales son los principales microorganismos esperables en muestras clínicas, además de conocer la prevalencia en general.

Abstract The epidemiology of the possible populations at risk of suffering an infection by anaerobic bacteria a national level is unknown, it should be encouraged the knowledge in the health services about this type of infections. Anaerobic bacteria are related in hospital environments as an important cause of morbidity, which is why it is convenient to know the epidemiology and prevalence of species involved. In the Bacteriology Laboratory of the Hospital San Juan de Dios, for three years, a total of 1545 patients suspected of anaerobic microorganisms in prereduced media were analyzed, through a screening was reduced to a total of 469 possible samples, which were sent to the Anaerobic Bacteriology Research Laboratory (LIBA) for its corresponding identification. Throughout the epidemiological weeks of the three years were found on average of 1.77 confirmed cases / week, with a positive sex ratio in favor of men. It was determined that only 245 of the samples sent had one or several strict anaerobic microorganisms representing 15.85% of the total, identifying 39 different species, in 306 isolated strains. The most important was the genus Bacteriodes, coming from the abdominal cavity followed by abscesses and skin wounds. The present study aims to present data that support the clinical importance of the search for anaerobic microorganisms and that help the analysts of bacteriology to guide which are the main expected microorganisms in clinical samples, in addition to knowing the prevalence in general.

Quorum sensing en la asociación beneficiosa de las bacterias con las plantas / Quorum sensing in beneficial plant-bacteria associations

Se conoce que el quorum sensing es un atributo común de muchas especies bacterianas y que puede ser un carácter universal de las bacterias. Actualmente se están describiendo a un paso más rápido nuevas señales y nuevos sistemas de regulación por quorum sensing y se han desarrollado las investigaciones acerca de la comunicación célula-célula en bacterias basada en el mecanismo de quorum sensing. En los ambientes naturales existen muchas bacterias que viven juntas y utilizan varias clases de moléculas señales. Dentro de las señales especie específicas predominan las acilhomoserín lactonas (AHLs), pero ya se han descrito una amplia diversidad de moléculas involucradas en la señalización célula-célula. Numerosos bioensayos y sistemas sensores se han desarrollado para la detección, caracterización y cuantificación de las AHLs. Se han obtenido evidencias de la acción de estas moléculas señales en la colonización de la rizosfera, el swarming, las interacciones simbióticas y la capacidad de interrumpir el proceso de señalización de otras bacterias que convivan en el mismo ambiente. Todas estas potencialidades de las bacterias que involucran el mecanismo de quorum sensing, pudieran ser utilizadas para fortalecerla acción estimuladora del crecimiento vegetal y el control biológico de patógenos en los agroecosistemas sostenibles.

The quorum sensing is a common attribute in some bacterial species. Currently, several signals and new regulation systems are describing and the researchers are very interested in the cell-cell communication based on quorum sensing mechanism. In the natural environments several bacteria are living together, then several types of signal molecules are using. The acylhomoserines lactones (AHLs), are predominant, but a wide range of molecules are involved in cell-cell communication. To detect, characterization and quantification of signals numerous bioassays and sensors systems were developed. It were demonstrated the action of signals molecules in the rhizosphere colonization, swarming, symbiotic interactions and the capacity to break the signaling process of another microorganism in the same environment. These potentialities of bacteria would be used to improve the plant growth stimulation and biological control of pathogens in sustainable agricultural.

Granules characteristics in the vertical profile of a full-scale upflow anaerobic sludge blanket reactor treating poultry slaughterhouse wastewater.

The performance and the granules characteristics of a 450 m(3) -UASB reactor operating for 1228 days, treating poultry slaughterhouse wastewater with an average COD reduction of 85% was examined. Granules were sampled in three different positions along the vertical central line of the reactor, revealing variations in the concentration of volatile total solids. Although the reactor had been in operation for an extended period of time, granule sizes of 0.5-1.5 mm appeared to predominate. The hollow core was well defined for granules with sizes ranging from 2 to 3 mm in all the sampling ports. The granules exhibited no layered microbial distribution and were packed with different morphotype cells intertwined randomly throughout the cross-section. Methanogenic Archaea predominated in the granules taken from every sampling port along the reactor. The results indicated that the characterization of the granules is a useful tool for the adoption of operational strategies toward optimization of UASB reactors.

Toxic effects of zinc on anaerobic microbiota from Zimapán Reservoir (Mexico).

The toxic effects of heavy metals have been extensively documented in different organisms. Nevertheless, a lack of information exists with regard to this topic in the case of autochthonous microorganism communities. The aim of this study was to evaluate the toxic effects of zinc on the anaerobic microorganisms present in the sediment and anoxic water of Zimapán Reservoir (Mexico), with particular focus on dissimilatory sulphate reducing bacteria. In the laboratory, a system of enrichment microcosms was set up with sediment and water from the reservoir. ATP, protein, carbohydrates and lactate and alcohol dehydrogenase activity were determined. The physicochemical parameters of the reservoir were evaluated over the course of one year. Sulphate reduction occurred in the reservoir throughout the year, but was most pronounced at the end of the wet season and during winter. In the field, increases in the rate of sulphate reduction coincided with the lowest levels of total phosphorus and hydrosoluble organic carbon. Zinc enrichment was observed to modify protein and carbohydrate content as well as to affect lactate and alcohol dehydrogenase activity. All responses followed a zinc concentration-response relationship and were dependent on reservoir physicochemical parameters. ATP content was used as a biomarker to evaluate the sublethal toxic effects of zinc. The acceptable threshold concentration of zinc in the aquatic and sediment enrichment microcosms was determined to be 0.06mgZn/L and 711.1mgZn/kg, respectively.

Halitosis: nuevas herramientas para un viejo desafío / Halitosis: new tools for an old challenge

La halitosis crónica es una condición en la que se producen olores desagradables en la cavidad bucal o la región nasalo y que no se corrigen con una higiene oral normal. El 90 por ciento de los casos se origina en la liberación de compuestos sulfurados volátiles (CSV) y otras moléculas malolientes por acción de bacterias anaerobias ubicadas en la región bucal, fundamentalmente en el dorso de la lengua. Las proteínas del mucus, células descamadas, restos de alimentos y la secreción postnasal, que se acumulan en la lengua, actúan de sustrato para la formación anaeróbica de los CSVs. El uso regular de limpialenguas reduce la carga microbiana bucal, el mal aliento y el riesgo de caries. El efecto de los enjuagues bucales es disímil, apareciendo como más eficaces aquellos que contienen dióxido de cloro estabilizado. La evolución de los pacientes puede determinarse en el consultorio mediante el Halimeter, un equipo portátil que detecta los niveles de CSVs o el BANA test, que identifica por métodos colorimétricos algunos gérmenes anaeróbicos asociados al mal aliento. Esta afección no mata, pero hay gente que muere por ella. Así lo plantean muchos trabajos psiquiátricos donde se señala que soledad de la persona inmersa en esta afección conduce a estados de depresión e inclusive al suicidio. El ignorar esta condición puede ser un ejercicio de mala praxis. Por ello el objetivo de este trabajo es informar cómo con un método sencillo se puede evitar una crisis de mayores proporciones. (AU)

Tissue reactions to a component of root canal system bacteria: lipoteichoic acid.

Lipoteichoic acid (LTA), present in Gram-positive microorganisms, has physiochemical characteristics that allow it to act as an immunogen. Due to polymicrobial characteristics of root canal infections, LTA can participate in the development of periapical disease. The reaction of the rat subcutaneous tissue to Teflon tube implants, filled with Fibrinol soaked in lipoteichoic acid (concentration of 150 microg/ml), was observed. Lipoteichoic acid provoked an inflammatory tissue reaction.

Tissue reactions to a component of root canal system bacteria: lipoteichoic acid

Lipoteichoic acid (LTA), present in Gram-positive microorganisms, has physiochemical characteristics that allow it to act as an immunogen. Due to polymicrobial characteristics of root canal infections, LTA can participate in the development of periapical disease. The reaction of the rat subcutaneous tissue to Teflon tube implants, filled with Fibrinol soaked in lipoteichoic acid (concentration of 150 æg/ml), was observed. Lipoteichoic acid provoked an inflammatory tissue reaction

Mobiluncus, ¿nuevo patógeno microbiano? / Mobiluncos: new microbian patogen?

La llamada vaginitis inespecífica, conocida en al actualidad como vaginosis bacteriana, es una entidad patológica de indudable relevancia. A su etiología polimicrobiana aceptada por la mayoría de investigadores se añade un nuevo género bacteriano: Mobiluncus, microrganismo anaerobio cuya posible participación en esta enfermedad genital se analiza en el presente artículo dentro de un contexto microbiológico y bioquímico