Different carboxyl-rich alicyclic molecules proxy compounds select distinct bacterioplankton for oxidation of dissolved organic matter in the mesopelagic Sargasso Sea

© The Author(s), 2020. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Liu, S., Parsons, R., Opalk, K., Baetge, N., Giovannoni, S., Bolanos, L. M., Kujawinski, E. B., Longnecker, K., Lu, Y., Halewood, E., & Carlson, C. A. Different carboxyl-rich alicyclic molecules proxy compounds select distinct bacterioplankton for oxidation of dissolved organic matter in the mesopelagic Sargasso Sea. Limnology and Oceanography, (2020), doi:10.1002/lno.11405.Marine dissolved organic matter (DOM) varies in its recalcitrance to rapid microbial degradation. DOM of varying recalcitrance can be exported from the ocean surface to depth by subduction or convective mixing and oxidized over months to decades in deeper seawater. Carboxyl‐rich alicyclic molecules (CRAM) are characterized as a major component of recalcitrant DOM throughout the oceanic water column. The oxidation of CRAM‐like compounds may depend on specific bacterioplankton lineages with oxidative enzymes capable of catabolizing complex molecular structures like long‐chain aliphatics, cyclic alkanes, and carboxylic acids. To investigate the interaction between bacteria and CRAM‐like compounds, we conducted microbial remineralization experiments using several compounds rich in carboxyl groups and/or alicyclic rings, including deoxycholate, humic acid, lignin, and benzoic acid, as proxies for CRAM. Mesopelagic seawater (200 m) from the northwest Sargasso Sea was used as media and inoculum and incubated over 28 d. All amendments demonstrated significant DOC removal (2–11 μmol C L−1) compared to controls. Bacterioplankton abundance increased significantly in the deoxycholate and benzoic acid treatments relative to controls, with fast‐growing Spongiibacteracea, Euryarcheaota, and slow‐growing SAR11 enriched in the deoxycholate treatment and fast‐growing Alteromonas, Euryarcheaota, and Thaumarcheaota enriched in the benzoic acid treatment. In contrast, bacterioplankton grew slower in the lignin and humic acid treatments, with oligotrophic SAR202 becoming significantly enriched in the lignin treatment. Our results indicate that the character of the CRAM proxy compounds resulted in distinct bacterioplankton removal rates of DOM and affected specific lineages of bacterioplankton capable of responding.We thank Z. Landry for the inspiring idea of SAR202 catabolism of CRAM. We thank the University of California, Santa Barbara Marine Science Institute Analytical Laboratory for analyzing inorganic nutrient samples. We thank C. Johnson for her help in FISH sample processing and BATS group in supporting our project. We thank N. K. Rubin‐Saika and R. Padula for their help with amino acid sample preparation. We thank Z. Liu, J. Xue, K. Lu, and Y. Shen for their help with amino acid protocol development and validation. We thank B. Stephens for his help on microscopic image analysis. We thank M. Dasenko and the staff of the CGRB at Oregon State University for amplicon library preparation and DNA sequencing. We are grateful for the help provided by the officers and crews of the R/V Atlantic Explorer. Bermuda Institute of Ocean Sciences (BIOS) provides us tremendous support in terms of facilities and lab space. We thank Bermuda government for its allowance of our water sampling and sample export (export permit number SP160904, issued 07 October 2016 under the Fisheries Act, 1972). This project was supported by Simons Foundation International's BIOS‐SCOPE program

Influence of host phylogeny and water physicochemistry on microbial assemblages of the fish skin microbiome

This is the final version. Available on open access from Oxford University Press via the DOI in this recordThe skin of fish contains a diverse microbiota that has symbiotic functions with the host, facilitating pathogen exclusion, immune system priming, and nutrient degradation. The composition of fish skin microbiomes varies across species and in response to a variety of stressors, however, there has been no systematic analysis across these studies to evaluate how these factors shape fish skin microbiomes. Here, we examined 1922 fish skin microbiomes from 36 studies that included 98 species and nine rearing conditions to investigate associations between fish skin microbiome, fish species, and water physiochemical factors. Proteobacteria, particularly the class Gammaproteobacteria, were present in all marine and freshwater fish skin microbiomes. Acinetobacter, Aeromonas, Ralstonia, Sphingomonas and Flavobacterium were the most abundant genera within freshwater fish skin microbiomes, and Alteromonas, Photobacterium, Pseudoalteromonas, Psychrobacter and Vibrio were the most abundant in saltwater fish. Our results show that different culturing (rearing) environments have a small but significant effect on the skin bacterial community compositions. Water temperature, pH, dissolved oxygen concentration, and salinity significantly correlated with differences in beta-diversity but not necessarily alpha-diversity. To improve study comparability on fish skin microbiomes, we provide recommendations for approaches to the analyses of sequencing data and improve study reproducibility.Natural Environment Research Council (NERC

Preparación y caracterización de fracciones de fibra en aceitunas (Variedad Hojiblanca)

Acid detergent fibre (ADF), neutral detergent fibre (NDF), insoluble fibre (IF) and soluble fibre (SF) were isolated from the flesh of Hojiblanca variety fresh green olives. Composition and recovery of polysaccharides, expressed as neutral sugars content, were studied for each one of these fractions.Se aísla fibra detergente ácido (ADF), detergente neutro (NDF), insoluble (FI) y soluble (FS), de pulpa de aceitunas verdes (variedad Hojiblanca) y se estudia la composición de cada una de estas fracciones, así como la recuperación de polisacáridos de las mismas (contenido en azúcares neutros)

El papel de la investigación para identificar oportunidades de mejora del regadío en Mauritania

Ponencia presentada en el I Congreso en Investigación en Agricultura para el desarrollo, celebrado en Madrid el 17 y 18 de octubre de 2011.-- Gómez Macpherson, H. et. al.La producción agrícola de Mauritania se concentra en el valle del río Senegal donde también se concentra gran parte de la población. Sólo un 0,5 % de la superficie mauritana es cultivable, y la tradicional dependencia de la agricultura pluvial ha provocado una alta inseguridad alimentaria; algo que quedó patente con las hambrunas causadas por los ciclos de sequía de los años 70. Los estados ribereños del río Senegal se organizaron entonces para desarrollar zonas regables con el objetivo de la seguridad alimentaria. En Mauritania, el regadío se orientó de forma exclusiva al cultivo del arroz, prácticamente desconocido en la zona. La ricicultura convive con sistemas tradicionales (pluviales y basados en el ciclo anual de inundación-recesión del río), pero el regadío es el sistema que garantiza la producción año a año. Sorprende por tanto que dos tercios de la superficie inicialmente regada se hayan abandonado. Esta paradoja fue el origen de la colaboración entre el Ministerio de Desarrollo Rural de Mauritania, el Instituto de Agricultura Sostenible y la Universidad Politécnica de Cataluña, concretada en proyectos financiados por AECID, y que tiene como objetivo ahondar en las razones del abandono del regadío y en buscar fórmulas para atajarlo. La colaboración se ha realizado sobre tres ejes principales: 1) comprender la interacción del regadío con los sistemas tradicionales de secano y de recesión de inundaciones; 2) diagnosticar el funcionamiento de los pequeños perímetros de riego; y 3) evaluar cultivos alternativos al arroz en términos de productividad de la tierra y del agua. Entre los cultivos regados de interés potencial se identificó el sorgo por ser del gusto de los habitantes del valle y cultivarse tradicionalmente en secano y tras la recesión del agua en suelos inundados.Los autores agradecen a los técnicos de campo y agricultores mauritanos por el trabajo realizado y al MDR y AECID por la financiación.Peer Reviewe

Linkages among dissolved organic matter export, dissolved metabolites, and associated microbial community structure response in the northwestern Sargasso Sea on a seasonal scale

© The Author(s), 2022. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Liu, S., Longnecker, K., Kujawinski, E., Vergin, K., Bolaños, L., Giovannoni, S., Parsons, R., Opalk, K., Halewood, E., Hansell, D., Johnson, R., Curry, R., & Carlson, C. Linkages among dissolved organic matter export, dissolved metabolites, and associated microbial community structure response in the northwestern Sargasso Sea on a seasonal scale. Frontiers in Microbiology, 13, (2022): 833252, https://doi.org/10.3389/fmicb.2022.833252.Deep convective mixing of dissolved and suspended organic matter from the surface to depth can represent an important export pathway of the biological carbon pump. The seasonally oligotrophic Sargasso Sea experiences annual winter convective mixing to as deep as 300 m, providing a unique model system to examine dissolved organic matter (DOM) export and its subsequent compositional transformation by microbial oxidation. We analyzed biogeochemical and microbial parameters collected from the northwestern Sargasso Sea, including bulk dissolved organic carbon (DOC), total dissolved amino acids (TDAA), dissolved metabolites, bacterial abundance and production, and bacterial community structure, to assess the fate and compositional transformation of DOM by microbes on a seasonal time-scale in 2016–2017. DOM dynamics at the Bermuda Atlantic Time-series Study site followed a general annual trend of DOC accumulation in the surface during stratified periods followed by downward flux during winter convective mixing. Changes in the amino acid concentrations and compositions provide useful indices of diagenetic alteration of DOM. TDAA concentrations and degradation indices increased in the mesopelagic zone during mixing, indicating the export of a relatively less diagenetically altered (i.e., more labile) DOM. During periods of deep mixing, a unique subset of dissolved metabolites, such as amino acids, vitamins, and benzoic acids, was produced or lost. DOM export and compositional change were accompanied by mesopelagic bacterial growth and response of specific bacterial lineages in the SAR11, SAR202, and SAR86 clades, Acidimicrobiales, and Flavobacteria, during and shortly following deep mixing. Complementary DOM biogeochemistry and microbial measurements revealed seasonal changes in DOM composition and diagenetic state, highlighting microbial alteration of the quantity and quality of DOM in the ocean.This project was funded by the Simons Foundation International’s BIOS-SCOPE program and US National Science Foundation (NSF OCE-1756105 for BATS cruises)

Experimental modulation of capsule size in Cryptococcus neoformans

Experimental modulation of capsule size is an important technique for the study of the virulence of the encapsulated pathogen Cryptococcus neoformans. In this paper, we summarize the techniques available for experimental modulation of capsule size in this yeast and describe improved methods to induce capsule size changes. The response of the yeast to the various stimuli is highly dependent on the cryptococcal strain. A high CO(2) atmosphere and a low iron concentration have been used classically to increase capsule size. Unfortunately, these stimuli are not reliable for inducing capsular enlargement in all strains. Recently we have identified new and simpler conditions for inducing capsule enlargement that consistently elicited this effect. Specifically, we noted that mammalian serum or diluted Sabouraud broth in MOPS buffer pH 7.3 efficiently induced capsule growth. Media that slowed the growth rate of the yeast correlated with an increase in capsule size. Finally, we summarize the most commonly used media that induce capsule growth in C. neoformans

Obonuco San Isidro nueva variedad mejorada de arveja para la zona de reconversión del trigo en Nariño.

El artículo presenta todas las características de la variedad mejorada de arveja, se muestra el origen genético, el comportamiento agronómico, la descripción varietal, la preparación del suelo, la fertilización, el sistema, densidad y época de siembra y el manejo integrado del cultivo como malezas, plagas, enfermedades y cosecha y la conclusión

“Tourism, water, and gender”—An international review of an unexplored nexus

This international literature review of the tourism–water nexus identifies a gender gap. Tourism development can affect water supply both quantitatively and qualitatively. Many regions will face considerable problems of water availability and quality, affecting their tourism sector and increasing competition with local residents, and other industries especially agriculture. This international review of literature explores the tourism–water nexus, comparing and contrasting literature published in English, Chinese, and Spanish. Securing access to safe water for continued tourism development is a common theme and the vast majority of work has focused on hotels including water pricing, water-saving practices and innovative management methods. In all continents, struggles are apparent, and the unsustainability of tourism is having impacts on water quantity and quality. This article identifies significant gaps in the literature including climate change, the energy-water nexus, and the links with the Sustainable Development Goals. Furthermore, studies from a gendered perspective are minimal and the potential for areas of further gendered studies within the tourism–water nexus are highlighted including intersectionality, water insecurity and sanitation, tourism and gender based violence, and additional unpaid care work

Obonuco Andina nueva variedad mejorada de arveja para la zona de economía campesina del sur de Nariño.

El artículo presenta todas las características de la variedad mejorada de arveja, se muestra el origen genético, el comportamiento agronómico, los atributos culinarios, las cualidades de mercadeo, la descripción varietal, el manejo agronómico como la preparación del suelo, la fertilización, el sistema, densidad y época de siembra y el manejo de malezas, plagas y enfermedades y las conclusiones.Obonuco Andina, variedad mejorada de arveja para el sistema de economía campesina de Nariñ

Endodontic regenerative treatment for internal radicular resorption using bio-ceramic material, case report

The internal resorption of the internal radicular conduct is a process than can be both physiological or pathological, being the osteoclasts, odontoclasts and dentinoclast responsible for said process. 49-year-old female patient, refers orthodontic treatment at age 20, attends a dental check-up due to pain when chewing. Dental organ (DO) #11 was diagnosed with internal root resorption and symptomatic, suppurative apical periodontitis. Treatment started performing an endodontic access and taking a conductometry reading with an apical foramen locator, using a precision hybrid instrumentation technique and applying hypochlorite irrigation, the intra-canal was medicated with chemically pure calcium hydroxide for 7 days. The canal obturation was repaired infiltrating a bio-ceramic material (BIO-C Sealer) followed by the placement of the single cone using a vertical condensation technique