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The microbial colonization on ancient murals attracts more and more attention since the threaten by microorganisms was first reported in Lascaux, Spain. However, the biodeterioration or biodegradation of mural paintings resulted by microorganisms is not clear yet. Especially the biological function of microbial communities in different conditions remained largely unaddressed. The two mausoleums of the Southern Tang Dynasty are the largest group of emperor mausoleums during the Five Dynasties and Ten Kingdoms period in China, which are of great significance to the study of the architecture, imperial mausoleum systems and art in the Tang and Song Dynasties. To make clear the species composition and metabolic functions of different microbial communities (MID and BK), we analyzed the samples from the wall paintings in one of the two mausoleums of the Southern Tang Dynasty with metagenomics method. The result showed totally 55 phyla and 1729 genera were detected in the mural paintings. The two microbial community structure were similar with the dominance of Proteobacteria, Actinobacteria and Cyanobacteria. However, the species abundance presented a significant difference between two communities at genus level --- MID is Lysobacter, Luteimonas are predominant in MID while Sphingomonas and Streptomyces are popular in BK, which is partially attributed to the different substrate materials of murals. As a result, the two communities presented the different metabolic patterns that MID community was mainly participated in the formation of biofilm as well as the degradation of exogenous pollutants while the BK was predominantly related to the photosynthesis process and biosynthesis of secondary metabolites. Taken together, these findings indicated the effect of environmental factor on the taxonomic composition and functional diversity of the microbial populations. The installation of artificial lighting needs to be considered carefully in the future protection of cultural relics. [ABSTRACT FROM AUTHOR]

Biogeography is a key concept associated with microbial terroir, which is responsible for the differentiation and uniqueness of wines. One of the factors influencing this microbial terroir is the vegetation, which in turn is influenced by climate, soil, and cultural practices. Remote sensing instruments can provide useful information about vegetation. This study analyses the relationship between NDVI, calculated using Sentinel-2 and Landsat-8 satellite images of different veraison dates, and microbial data obtained in 2015 from 14 commercial (organic and conventional) vineyards belonging to four Designations of Origin (DOs) from Galicia (northwest Spain). Microbial populations in grapes and musts were identified using PCR techniques and confirmed by sequencing. Statistical analyses were made using PCA, CCA, TB-PLS, and correlation analyses. This study confirms that the NDVI is positively correlated with the diversity of yeasts, both in grapes' surface and must samples. Moreover, the results of this study show: (i) Sentinel-2 images, as well as Landsat-8 images, can establish differences in NDVI related to yeast terroir in grapes and musts, as it is the most relevant DO factor, (ii) Sentinel-2 NDVI and yeast biogeography are moderately to strongly correlated, (iii) Sentinel-2 achieved a better delimitation of the DOs than Landsat-8 and can establish more accurate differences in NDVI–yeast terroir correlations, and (iv) a higher NDVI was associated with the yeast biogeographical patterns of the DOs with higher species richness (S) consisting of weakly fermenting yeasts (Hanseniaspora uvarum, Pichia spp., Starmerella bacillaris, and Zygosaccharomyces spp). However, NDVI values did not correlate well with biogeographic patterns of yeasts previously studied at frequency level (proportion or percentage of each species) in each particular DO. This study suggests that satellite imagery has the potential to be a valuable tool for wine quality management and a decision-making instrument for DO regulators and winegrowers. [ABSTRACT FROM AUTHOR]

Achieving a healthy gut with a suitable microbial population in place will maximize the health and lifetime performance of piglets and, concurrently, profitability. Natural nutritional strategies that promote gut health and development in young pigs without zinc oxide (ZnO) are gaining considerable interest. Alltech's Seed, Feed, Weed (SFW) program is designed to promote favorable microbial communities in the gut, optimize gut structures, and support the immune system; all of which will positively impact the growth and health of young piglets. The objective of this study was to investigate the effect of the SFW piglet program as an alternative to ZnO supplementation on the growth, feed efficiency and mortality of newly weaned pigs. Newly weaned pigs were allocated to one of two dietary treatments in 3 experiments. All experiments were carried out on commercial pig units in Spain. Dietary treatments were a basal pre-starter and starter diet containing 3,000 ppm ZnO (CONTROL), and a SFW piglet pre-starter and starter pack containing 0 ppm ZnO (SFW). In Exp. 1, pigs (n = 431) were weaned at 28 days old and fed the experimental pre-starter diets for 9 days. In Exp. 2, pigs (n = 295) were weaned at 28 days old and fed the experimental pre-starter and starter diets for 35 days. In Exp. 3, pigs (n = 311) were weaned at 28 days old and fed the experimental pre-starter and starter diets for 21 days. Pig performance was recorded. In experiment 1, SFW-fed pigs had similar average daily gain (ADG; 142 g/d vs 148 g/d) and average daily feed intake (ADFI; 149 g/d vs. 167 g/d) to CONTROL fed pigs. Feed efficiency (FE) was 1.05 and 1.13 for SFW and CONTROL piglets, respectively, resulting in SFW fed piglets being heavier at the end of the treatment period (7.65 kg vs. 7.45 kg). In experiment 2, overall, ADG (308 g/d vs. 316 g/d) and ADFI (423 g/d vs. 444 g/d) were similar between SFW and CONTROL fed piglets, respectively. Th SFW piglets had greater FE than CONTROL pigs (1.37 vs. 1.41). In experiment 3, there was no effect of treatment on ADG (356 g/d vs. 355 g/d) and ADFI (410 g/d vs. 420 g/d) or piglet body weight at the end of the study (12.8 kg vs. 12.7 kg). Feed efficiency was improved (1.21 vs. 1.24) and piglet mortality was reduced (3.4 % vs. 6.9 %) in SFW fed piglets compared with CONTROL fed piglets. In conclusion, the SFW program may prove to be a suitable alternative to ZnO by positively influencing the gut health of piglets and ensuring that piglet performance and health is maintained in the absence of ZnO. [ABSTRACT FROM AUTHOR]

Abstract: With the recent detection of MRSA (methicillin-resistant Staphylococcus aureus) infections in patients lacking health care-related risk factors, the term community-acquired MRSA (CA-MRSA) has been become widely recognised. Many cases of CA-MRSA spreading to the community have been described worldwide. The aim of this study was to determine the features of CA-MRSA isolates from Tenerife Island. Toward this end, one hundred MRSA isolates were collected from eight different health regions, and their molecular features were investigated. This study revealed a wide variety of MRSA clones, including an emergent ST: ST1434 (CC8) and two new spa types, t7575 (ST125) and t7678 (ST22). The PVL genes were found in only five isolates belonging to unrelated lineages, ST8, ST30 and ST22, which could indicate at least three independent introductions of PVL+ strains to Tenerife. Moreover, we detected that hospital MRSA clones, like EMRSA-15 and EMRSA-16, had spread to the community and are now circulating in both environments. Therefore, in our study, the CDC’s rules were not specific enough to distinguish CA-MRSA from HA-MRSA. Thus, we think that the current epidemiological information is not enough to discriminate between both MRSAs, and it is necessary for prevention guidelines to include the routine determination of at least the genetic background, the antimicrobial susceptibility profile, and the PVL genes of each MRSA isolate. [Copyright &y& Elsevier]

Diversity of lactic acid bacteria (LAB) species has been analyzed for three consecutive years (2006, 2007, and 2008) during alcoholic and malolactic fermentations of Tempranillo wine in a winery at La Rioja. The results showed differences in malolactic fermentation duration, and in both diversity of LAB species and diversity of Oenococcus oeni genotypes. O. oeni was shown to be the predominant species (73% of total isolates). Monitoring the different strains of O. oeni using pulsed-field gel electrophoresis of chromosomal DNA digested with SfiI and ApaI allowed detection of a total of 37 distinct genotypes, most of them comprised at least two isolates. Six appeared in more than one vintage, one of them being present in the three studied years. Moreover, four genotypes were indistinct of the strains isolated from the air of this same winery in 2007 vintage. The frequency of participation of each genotype varied from year to year, thus dominant genotypes at one year were minority or not present at another year. This suggests that distinct indigenous O. oeni strains are better adapted to the different winery conditions every year. Predominant genotypes that appeared in more than one vintage and lead to quality wines with low histamine contents could be considered as interesting for selecting of new malolactic starter cultures. [ABSTRACT FROM AUTHOR]

Floral nectar of insect-pollinated plants often contains dense yeast populations, yet little quantitative information exists on patterns and magnitude of species richness of nectar-dwelling yeasts in natural plant communities. This study evaluates yeast species richness at both the plant community and plant species levels in a montane forest area in southern Spain, and also explores possible correlations between the incidence of different yeast species in nectar and their reported tolerance to high sugar concentrations, and between yeast diversity and pollinator composition. Yeast species occurring in a total of 128 field-collected nectar samples from 24 plant species were identified by sequencing the D1/D2 domain of the large subunit rDNA, and rarefaction-based analyses were used to estimate yeast species richness at the plant community and plant species levels, using nectar drops as elemental sampling units. Individual nectar samples were generally characterized by very low species richness (1.2 yeast species/sample, on average), with the ascomycetous Metschnikowia reukaufii and Metschnikowia gruessii accounting altogether for 84.7% of the 216 isolates identified. Other yeasts recorded included species in the genera Aureobasidium, Rhodotorula, Cryptococcus, Sporobolomyces, and Lecythophora. The shapes and slopes of observed richness accumulation curves were quite similar for the nectar drop and plant species approaches, but the two approaches yielded different expected richness estimates. Expected richness was higher for plant species-based than for nectar drop-based analyses, showing that the coverage of nectar yeast species occurring in the region would be improved by sampling additional host plant species. A significant correlation was found between incidence of yeast species in nectar and their reported ability to grow in a medium containing 50% glucose. Neither diversity nor incidence of yeasts was correlated with pollinator composition across plant species. [ABSTRACT FROM AUTHOR]

Abstract: The dilution technique, combined with identification and enumeration of pico-, nano- and micro-plankton by microscopy, was used to estimate microzooplankton impact on the microbial community in surface waters of a coastal embayment on the NW Iberian upwelling system. Microzooplankton were important consumers of autotrophic and heterotrophic plankton in this system, feeding up to 93% of standing stock and more than 100% of production of several groups. Heterotrophic bacteria and heterotrophic picoflagellates experienced the highest and constant impact, with 75–84% of their standing stocks and 85–102% of their production being channelled through the microbial food web. Pico- and nano-phytoplankton were also consumed, although maximum grazing occurred on diatoms during upwelling events, coinciding with highest primary production. Predation on pico-nano-heterotrophs was especially relevant under downwelling conditions, when consumption of total carbon and particularly autotrophic carbon was considerably lower than during upwelling. The results suggest that the existence of a multivorous food web, extending from the microbial loop to the herbivorous food web, could be a major feature in this coastal upwelling system. The microbial loop, which occurs as a permanent background in the system, would contribute to sustain the microbial food web during downwelling, whereas the herbivorous food web could coexist with a microbial food web based on large diatoms during upwelling. The multivorous food web would partially divert diatoms from sinking and hence favour the retention of organic matter in the water column. This could enhance the energy transfer to higher pelagic trophic levels in coastal upwelling systems. [ABSTRACT FROM AUTHOR]

Abstract: The ecology and the population dynamics of lactic acid bacteria during malolactic fermentation of Tempranillo wine made at five wineries in Castilla-La Mancha were analysed for two consecutive vintages (years 2006 and 2007). This microbiota was typed using Randomly Amplified Polymorphic DNA-Polymerase Chain Reaction (RAPD-PCR) subsequently identified using both molecular and phenotypic methods. Oenococcus oeni was the predominant species. Genotypes varied considerably in both of the vintages from each winery, although a number of coincident genotypes were found in each one. Three genotypes were present in all the wineries in at least one of the vintages. These results confirm the existence of a coincident population of O. oeni genotypes that may be considered endemic to this wine region and that seem to play an important role in all the vinifications. [Copyright &y& Elsevier]

Abstract: Classical culturing and denaturing gradient gel electrophoresis (DGGE) techniques have been used for studying the microbial diversity and dynamics of the traditional Spanish Casín cheese during manufacturing and ripening. As with other starter-free cheeses made from raw milk, the microbial diversity of Casín was shown to be high by both culturing and DGGE analyses. The culture technique showed that lactic acid bacteria (LAB) species constituted the majority of the microbial populations. Of the 14 bacterial species identified, Lactococcus garvieae was predominant in the three-day-old cheese sample, although it was replaced by Lactococcus lactis subsp. lactis at day 30. As expected, the DGGE profiles obtained were complex, consisting, depending on the sample, in five to ten different amplification bands. Among these, a band corresponding to Streptococcus thermophilus was observed throughout the whole manufacturing process. This species had never been identified from traditional Spanish cheeses previously. Culturing and molecular methods showed high populations of undesirable microorganisms, arguing for a required improvement in the hygiene of Casín manufacture. Random amplification of polymorphic DNA (RAPD) profiling suggested that the L. garvieae and L. lactis populations were composed of one and five strains, respectively. In addition, only a single L. lactis RAPD pattern was stably maintained from day three to day 30, indicating high succession of strains along ripening. After a thoroughly characterisation, strains of the two Lactococcus species could be used in designing specific starter cultures for Casín. Additional species (such as Lactobacillus plantarum and Corynebacterium variabile) might be included as adjunct cultures. [Copyright &y& Elsevier]

The aquifer system of Doñana (SW Spain) represents the most important freshwater source in the Doñana Natural Area. Its spatiotemporal dynamics favours the hydrological connection between surface and subsurface ecosystems, and promotes matter fluxes among the different terrestrial and aquatic systems present here. This aquifer has been intensively studied from a hydrogeological point of view but little is known from an ecological perspective. In order to understand the ecological roles played by microbial communities in this system, we conducted a long-term seasonal study of bacterial abundance, cell biomass, bacterial biomass and functional activities over a 2-year period. Bacterial abundance ranged between 2.11 ± 1.79 × 105 and 8.58 ± 6.99 × 107 bacteria mL−1 groundwater, average cell biomass was estimated to be 77.01 ± 31.56 fgC and bacterial biomass varied between 8.99 ± 4.10 × 10−2 and 5.65 ± 0.70 µgC mL−1. Iron-related bacteria showed the highest activities among the functional groups studied. Moreover, among the variables that usually control spatial distributions of microbial communities in aquifer systems, depth did not have a relevant effect on this aquifer, at least in the range of depths studied, but grain size, probably due to its direct effects on hydrogeological parameters, such as permeability or porosity, appeared to exert moderate control, principally in terms of bacterial abundance. Finally, significant seasonal differences in the means of these microbiological variables were also observed; temperature seems to be the main factor controlling the temporal distribution of microbial communities in this aquifer system. [ABSTRACT FROM AUTHOR]

In dense stratified systems such as microbial mats, photosynthesis and respiration are coupled due to a tight spatial overlap between oxygen-producing and -consuming microorganisms. We combined microsensors and a membrane inlet mass spectrometer with two independent light sources emitting in the visible (VIS) and near infrared (NIR) regions to study this coupling in more detail. Using this novel approach, we separately quantified the activity of the major players in the oxygen cycle in a hypersaline microbial mat: gross photosynthesis of cyanobacteria, NIR light-dependent respiration of Chloroflexus-like bacteria (CLB) and respiration of aerobic heterotrophs. Illumination by VIS light induced oxygen production in the top ∼1 mm of the mat. In this zone CLB were found responsible for all respiration, while the contribution of the aerobic heterotrophs was negligible. Additional illumination of the mat with saturating NIR light completely switched off CLB respiration, resulting in zero respiration in the photosynthetically active zone. We demonstrate that microsensor-based quantification of gross and net photosyntheses in dense stratified systems should carefully consider the NIR light-dependent behaviour of CLB and other anoxygenic phototrophic groups. [ABSTRACT FROM AUTHOR]

The degree of degradation of soils can be measured by reference to a variety of chemical, physical, biochemical and biological properties, the last two being particularly sensitive to the changes that take place. Among these parameters, those related with the soil carbon content, such as total organic carbon and microbial biomass carbon, are of the greatest interest although others are also important indicators of microbial activity, including ATP and phosphatase activity. This study looks at the microbial activity of various soils in SE Spain which present different degrees of plant cover. The results demonstrate that vegetation is of fundamental importance for the development of microbial populations and their activity since soils with a substantial vegetal cover showed higher values for the above parameters than those with a reduced cover, which are more degraded. A seasonal study of the soil properties showed that the time of year exercises an important influence on the parameters that are indicative of microbial activity. [Copyright &y& Elsevier]

Previous studies have provided evidence that chemical biocides can condition the behaviour of microbial populations, thereby promoting recolonization by some groups of microorganisms. We conducted a year-long study to evaluate the extent to which fungal and bacterial communities are affected by the biocidal treatments Biotin R®, Biotin T®, Preventol RI80®, New Des 50®, benzalkonium chloride and an ethanol-water (1:1) mixture, used to remove Apatococcus lobatus from the granite walls of the San Martiño Pinario Monastery in Santiago de Compostela (NW Spain). Bacterial, fungal, algal and cyanobacterial concentrations were enumerated via microscopic counts of colony-forming units on agar plates, one, six and twelve months after application of the biocidal treatments. Cultivable species were further characterized by morphological taxonomic analysis (algae and fungi) and DNA analysis by sequencing of 16S rDNA gene (bacteria) and the ITS region plus the D1/D2 region of the 28S rDNA gene (fungi) before and after one-year treatment. None of the treatments led to overgrowth of bacteria or fungi, while benzalkonium chloride and water (used as control) treatments were the most effective in preventing bacterial recolonization and Biotin T® was the most effective in preventing fungal recolonization. Although the bacterial population did not increase in numbers after any of the treatments, the diversity was altered, with Bacillus halotolerans disappearing and Bacillus pumilus and Brachybacterium paraconglomeratum appearing in the areas treated with biocides. In fungi, Eutypa sp. was eliminated with all biocides except with Preventol RI80® and no species was promoted. • None of the treatments led to overgrowth of bacteria and fungi. • Treatments had different effects on algal, bacterial and fungal communities. • BC and water were the best treatments for removing bacteria and Biotin T® for fungi. • Cultivable species either eliminated or favoured by treatments were identified. [ABSTRACT FROM AUTHOR]

Halophilic microorganisms can be an excellent source of useful compounds for industrial applications. However, the microbial population inhabiting extreme saline environments has been under-estimated, due to difficulties encountered in the isolation and cultivation of these microorganisms. The solar salterns located in the Odiel marshlands (Huelva), at the southwest of Spain, are an excellent example of a poorly explored hypersaline environment. In this work, we used two culture-independent methods to study the prokaryotic diversity present in the brine ponds at 33% salinity. We constructed and characterized libraries of PCR-amplified 16S rRNA genes with genomic DNA extracted from a water sample as template; and we used 16S rRNA Next-Generation Sequencing (NGS) based on the Illumina MiSeq platform to profile the same genomic sample. Furthermore, the ability of this microbial population to excrete haloenzymes was tested on agar plates. This work entails the first study of the aquatic microbial composition in this environment, where we found only one bacterial species, Salinibacter ruber, and a high diversity of archaea. Moreover, we demonstrated that NGS and clone library approaches were comparable regarding the estimation of the major genera found in the sample, including Halorubrum, Haloquadratum, Halonotius and Halobellus. Finally, we showed that the biomass presented different hydrolase activities, comprising a-amylase, protease, lipase/esterase, cellulase and laccase. Further studies will focus on the isolation and identification of the strains with the higher activity for each enzyme, followed by the optimization of the parameters that enable the best activity. [ABSTRACT FROM AUTHOR]

Halophiles are widespread in the three domains of life; nevertheless, there are few halophilic eukaryotes able to thrive in extreme salinity conditions in comparison to prokaryotes. For that reason, most research on microorganisms adapted to hypersaline habitats has been focused on Archaea and Bacteria, with microbial eukaryotes receiving much less attention. Hereby, we expose a research about eukaryotic microorganisms living in a solar saltern pond located in the Odiel marshlands (Huelva), at the southwest of Spain. In this work, we used a culture- independent method to study the eukaryotic population in the brine ponds at 33% salinity. We constructed and characterized a library of PCR amplified 18S rRNA genes with genomic DNA extracted from a water sample as template. In addition, we isolated several microalgae strains and we identified them by PCR amplified 18S rRNA gene sequence comparison with DNA databases. Finally, we studied their pigments composition by High Performance Liquid Chromatography. This study means the first characterization of the eukaryotic microbial diversity of the extreme saline water of this environment. We found diverse microalgae belonging to the Dunaliella genus, and various protozoan predators related to the Colpodella genus. Concerning the pigments, we found that the isolated microalgae produced neoxanthin, violaxanthin, antheraxanthin, lutein, chlorophyll a, chlorophyll b, and ß-carotene. Following studies will be focused on the bioactive capacity of these pigments, testing their antitumor, antimicrobial and antioxidant activities. [ABSTRACT FROM AUTHOR]