Halotolerant bacteria in the efflorescences of a deteriorated church

7 pages, 6 figures, 3 tables, 18 references.--Proceedings of the 5th International Symposium, celebrado del 5-8, abril, 2000, en Sevilla, España.[EN]: A study on the composition of the efflorescences from the Church of Saint Jerome, Granada, Spain, and their influence on the distribution ofthe bacterial communities was carried out. The composition of the efflorescences varied depending on the location of the sampling point. The colony foming units (cfu) was related with the type of salt, with a clear difference between halite and epsomite/hexahydrite. The most abundant genera were Bacillus and Micrococcus and the abundance of bacilli could be explained by their osmotic adaptation to halophilic environments.[ES]: Se ha determinado la composición de las eflorescencias de la iglesia de San Jerónimo, en Granada, España, y relacionado con la presencia de comunidades específicas de bacterias. Existe una conexión entre el tipo de sales y las comunidades bacterianas; así, la epsomita, la sal más abundante en el templo, origina la selección de comunidades capaces de crecer a concentraciones de hasta,15% de esta sal. Sin embargo, las bacterias que basan su halotolerancia en la halita presentan un crecimiento comparativamente menor y no son significativamente estimuladas por la presencia de epsomita. Los géneros más abundantes son Bacillus y Micrococcus. La abundancia de bacilos se debe a su adaptación osmótica a ambientes salinos.This work was supported by the European Commission, project ENV4-CT98-0705, and the Research Groups RNM-179 and 201 from the Community of Andalusia.Peer reviewe

Morning and Afternoon Sampling and Herbage Chemical Composition of Rotationally Stocked Elephant Grass cv. Napier

Nutrient intake by grazing animals depends on the amount of dry matter consumed and its chemical composition. Forage grasses, as with any other plants, produce assimilates during the day via photosynthesis to sustain live tissues, plant growth and organic reserves (Taiz and Zeiger 2013). In that context, herbage chemical composition may vary according to variations in the photosynthesis-respiration balance throughout the day. From dawn to dusk the balance increases and herbage dry matter content as well as concentration of soluble carbohydrates increase, the reverse happening from dusk to dawn. That could interfere with nutritive value and nutrient intake of grazing animals (Delagarde 2000), since for a given bite volume the amount of herbage and its composition could vary depending on the time of the day. That could have implications for rotationally managed pastures, indicating a potential effect of time of changing animals from one paddock to the other as a management strategy. Against that background, the objective of this experiment was to evaluate dry matter (DM) content and the concentration of soluble carbohydrates (SC), crude protein (CP), neutral (NDF) and acid (ADF) detergent fibre in herbage samples harvested during the morning and afternoon periods from rotationally stocked elephant grass cv. Napier

Genetic connectivity between Atlantic bluefin tuna (ABFT) Larvae Spawned in the GOM and MED

Highly migratory Atlantic bluefin tuna (ABFT) is managed as two stocks, Western and Eastern. Western ABFT spawn mainly in the Gulf of Mexico (GOM) and Eastern ABFT in the Mediterranean Sea (MED) (1). Understanding connectivity between ABFT populations is important for conservation and management of this valuable fishery resource that has been exploited for centuries. ABFT are highly mixed, with multiple disciplines supporting weak structuring between Western and Eastern stocks (1). Concerning genetics, subtle structuring of ABFT populations across the Atlantic Ocean has been the conclusion of studies describing genetic tools for traceability (2,3). Larval fish provide the genetic signal of successful breeders and have occasionally been genetically characterized with juveniles (young-of-the-year, YOY) collected in nursery areas. For the first time, cooperative field collection of tuna larvae during 2014 in the main spawning area for each stock enabled us to assess the structuring of ABFT genetic diversity in a precise temporal and spatial frame exclusively through larvae (5). Partitioning of genetic diversity at nuclear microsatellite loci and in the mitochondrial control region resulted in low significant fixation indices. Individual-based clustering analysis of larval ABFT genetic diversity indicate apparent connectivity between the GOM and MED spawning grounds that could support the hypothesis of mixing of breeders belonging to different stocks.This collaborative study was supported by "ECOLATUN" PROJECT CTM2015-68473-R (MINECO/FEDER) funded by Spanish Ministry of Economy and Competitiveness; "TUNAGEN" project funded by IEO; and "BLUEFIN" project financed by IEO and Balearic Island Observing and Forecasting System (SOCIB). This research was funded by NASA (NNX11AP76G S07), the NOAA National Marine Fisheries Science Service through the Southeast Fisheries Science Center, as well as by Cooperative Institute for Marine and Atmospheric Studies under Cooperative Agreement NA15OAR43200064 at the University of Miami. There was no additional external funding received for this study. The scientific results and conclusions, as well as any views or opinions expressed herein, are those of the author(s) and do not necessarily reflect those of NOAA or the Department of Commerce

Hydroxyapatite based hybrid dental materials with controlled porosity and improved tribological and mechanical properties

Hybrid dental materials were designed with controlled porosity and improved tribological and mechanical properties. These materials are based on hydroxyapatite (HAp) and reinforced with two different types of ceramic particles, alumina and silica, to support the high stresses and the continuous scratching produced during mastication. The agglutinant phase is an alkyd polyester polyurethane with high abrasion resistance that adheres well to surfaces containing OH groups. Porosity of the materials was controlled using sodium acetate powder of specified particle size as a pore former, thereby providing the materials with a morphology that resembles real teeth. The composition, structure and morphology were evaluated through several analytical techniques; results of scanning electron microscopy, dynamic light scattering, Fourier transform infrared spectroscopy, X-ray diffraction, induced coupled plasma optical emission spectroscopy and densitometry are reported. The ceramic powders incorporated (HAp, alumina and silica) were a combination of micro-and nanoscale particles; this use of different sized particles improved the packing and consequently the mechanical and tribological properties of the dental materials. Tribological features are explained from results of microscratch testing and abrasion resistance. The elastic modulus from mechanical testing is compared for the entire set of hybrid dental composites developed

Laboratory-induced endolithic growth in calcarenites: biodeteriorating potential assessment

This study is aimed to assess the formation of photosynthetic biofilms on and within different natural stone materials, and to analyse their biogeophysical and biogeochemical deterioration potential. This was performed by means of artificial colonisation under laboratory conditions during 3 months. Monitoring of microbial development was performed by image analysis and biofilm biomass estimation by chlorophyll extraction technique. Microscopy investigations were carried out to study relationships between microorganisms and the mineral substrata. The model applied in this work corroborated a successful survival strategy inside endolithic microhabitat, using natural phototrophic biofilm cultivation, composed by cyanobacteria and algae, which increased intrinsic porosity by active mineral dissolution. We observed the presence of mineral-like iron derivatives (e.g. maghemite) around the cells and intracellularly and the precipitation of hausmannite, suggesting manganese transformations related to the biomineralisation.Fundação para a Ciência e a Tecnologia (FCT

Contribution of the Microbial Communities Detected on an Oil Painting on Canvas to Its Biodeterioration

In this study, we investigated the microbial community (bacteria and fungi) colonising an oil painting on canvas, which showed visible signs of biodeterioration. A combined strategy, comprising culture-dependent and -independent techniques, was selected. The results derived from the two techniques were disparate. Most of the isolated bacterial strains belonged to related species of the phylum Firmicutes, as Bacillus sp. and Paenisporosarcina sp., whereas the majority of the non-cultivable members of the bacterial community were shown to be related to species of the phylum Proteobacteria, as Stenotrophomonas sp. Fungal communities also showed discrepancies: the isolated fungal strains belonged to different genera of the order Eurotiales, as Penicillium and Eurotium, and the non-cultivable belonged to species of the order Pleosporales and Saccharomycetales. The cultivable microorganisms, which exhibited enzymatic activities related to the deterioration processes, were selected to evaluate their biodeteriorative potential on canvas paintings; namely Arthrobacter sp. as the representative bacterium and Penicillium sp. as the representative fungus. With this aim, a sample taken from the painting studied in this work was examined to determine the stratigraphic sequence of its cross-section. From this information, “mock paintings,” simulating the structure of the original painting, were prepared, inoculated with the selected bacterial and fungal strains, and subsequently examined by micro-Fourier Transform Infrared spectroscopy, in order to determine their potential susceptibility to microbial degradation. The FTIR-spectra revealed that neither Arthrobacter sp. nor Penicillium sp. alone, were able to induce chemical changes on the various materials used to prepare “mock paintings.” Only when inoculated together, could a synergistic effect on the FTIR-spectra be observed, in the form of a variation in band position on the spectrum.The FTIR analyses performed in this study were financed by the Junta de Andalucía (RNM-325 group). The molecular analyses performed in this study were financed by the Austrian Science Fund (FWF) project ‘Hertha-Firnberg T137’ and the Spanish Ministry of Science and Innovation (Project CTQ2008-06727-C03-03). G. Piñar also thanks the “Elise-Richter V194-B20” projects