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Sample records for archaeal phylogenetic diversity

  1. Phylogenetic Diversity of Archaea and the Archaeal Ammonia Monooxygenase Gene in Uranium Mining-Impacted Locations in Bulgaria

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    Galina Radeva

    2014-01-01

    Full Text Available Uranium mining and milling activities adversely affect the microbial populations of impacted sites. The negative effects of uranium on soil bacteria and fungi are well studied, but little is known about the effects of radionuclides and heavy metals on archaea. The composition and diversity of archaeal communities inhabiting the waste pile of the Sliven uranium mine and the soil of the Buhovo uranium mine were investigated using 16S rRNA gene retrieval. A total of 355 archaeal clones were selected, and their 16S rDNA inserts were analysed by restriction fragment length polymorphism (RFLP discriminating 14 different RFLP types. All evaluated archaeal 16S rRNA gene sequences belong to the 1.1b/Nitrososphaera cluster of Crenarchaeota. The composition of the archaeal community is distinct for each site of interest and dependent on environmental characteristics, including pollution levels. Since the members of 1.1b/Nitrososphaera cluster have been implicated in the nitrogen cycle, the archaeal communities from these sites were probed for the presence of the ammonia monooxygenase gene (amoA. Our data indicate that amoA gene sequences are distributed in a similar manner as in Crenarchaeota, suggesting that archaeal nitrification processes in uranium mining-impacted locations are under the control of the same key factors controlling archaeal diversity.

  2. Bacterial and Archaeal Diversity From the Eastern Lau Spreading Center

    Science.gov (United States)

    Reysenbach, A.; Banta, A.; Kelly, S.; Kirshstein, J.; Voytek, M.

    2005-12-01

    Due to the diversity of venting styles, geological settings and variations in fluid geochemistry, the Valu Fa Ridge and Eastern Lau Spreading Center (ELSC) provide a unique opportunity to explore the effects geological and geochemical variables on patterns of microbial phylogenetic and metabolic diversity. High temperature sulfides, diffuse flow fluids and microbial mats were collected from six active vent fields on the Valu Fa Ridge and Eastern Lau Spreading Center during the R/V Melville cruise TUIM05MV. All samples were subsampled for molecular and microbial culturing purposes. The archaeal and bacterial 16S rRNA genes were amplified by PCR from a selection of samples. Additionally, the presence of Aquificales and an unidentified lineage, the DHVE archaeal group, was explored using PCR primers specific for these groups. A selection of DNAs were also screened for functional genes that are diagnostic for certain pathways, viz, aclB (reductive TCA cycle), mcrA (methanogenesis), nirS and nirK (nitrite reduction), amoA (ammonia oxidation). Culturing of thermophiles, both acidophiles and neutrophiles, was initiated. Over 20 hydrogen oxidizing (hydrogen and oxygen) or nitrate reducing (hydrogen and nitrate) chemolithoautotrophs were isolated as colonies and grow at 70 degrees C. All are related to Persephonella hydrogenophila, with the exception of 2 cultures that perhaps represent new species of Hydrogenivirga and Aquifex. Preliminary analysis of patterns of Aquificales diversity using both culturing and molecular approaches suggest that the distributions of this group alone are very different from that observed at other hydrothermal sites such as along the East Pacific Rise or Central Indian Ridge. As yet, the most commonly isolated Aquificales, P. marina, has not been detected in enrichment cultures from ELSC, and the diversity of Aquificales-related sequences is much greater than detected from sites along the EPR. It is therefore also likely, that patterns of

  3. Archaeal diversity in Icelandic hot springs

    DEFF Research Database (Denmark)

    Kvist, Thomas; Ahring, Birgitte Kiær; Westermann, Peter

    2007-01-01

    Whole-cell density gradient extractions from three solfataras (pH 2.5) ranging in temperature from 81 to 90 degrees C and one neutral hot spring (81 degrees C, pH 7) from the thermal active area of Hveragerethi (Iceland) were analysed for genetic diversity and local geographical variation of...

  4. Land-use systems affect Archaeal community structure and functional diversity in western Amazon soils

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    Acácio Aparecido Navarrete

    2011-10-01

    Full Text Available The study of the ecology of soil microbial communities at relevant spatial scales is primordial in the wide Amazon region due to the current land use changes. In this study, the diversity of the Archaea domain (community structure and ammonia-oxidizing Archaea (richness and community composition were investigated using molecular biology-based techniques in different land-use systems in western Amazonia, Brazil. Soil samples were collected in two periods with high precipitation (March 2008 and January 2009 from Inceptisols under primary tropical rainforest, secondary forest (5-20 year old, agricultural systems of indigenous people and cattle pasture. Denaturing gradient gel electrophoresis of polymerase chain reaction-amplified DNA (PCR-DGGE using the 16S rRNA gene as a biomarker showed that archaeal community structures in crops and pasture soils are different from those in primary forest soil, which is more similar to the community structure in secondary forest soil. Sequence analysis of excised DGGE bands indicated the presence of crenarchaeal and euryarchaeal organisms. Based on clone library analysis of the gene coding the subunit of the enzyme ammonia monooxygenase (amoA of Archaea (306 sequences, the Shannon-Wiener function and Simpson's index showed a greater ammonia-oxidizing archaeal diversity in primary forest soils (H' = 2.1486; D = 0.1366, followed by a lower diversity in soils under pasture (H' = 1.9629; D = 0.1715, crops (H' = 1.4613; D = 0.3309 and secondary forest (H' = 0.8633; D = 0.5405. All cloned inserts were similar to the Crenarchaeota amoA gene clones (identity > 95 % previously found in soils and sediments and distributed primarily in three major phylogenetic clusters. The findings indicate that agricultural systems of indigenous people and cattle pasture affect the archaeal community structure and diversity of ammonia-oxidizing Archaea in western Amazon soils.

  5. Distribution and Diversity of Archaeal Ammonia Monooxygenase Genes Associated with Corals▿ †

    OpenAIRE

    Beman, J. Michael; Roberts, Kathryn J.; Wegley, Linda; Rohwer, Forest; Francis, Christopher A.

    2007-01-01

    Corals are known to harbor diverse microbial communities of Bacteria and Archaea, yet the ecological role of these microorganisms remains largely unknown. Here we report putative ammonia monooxygenase subunit A (amoA) genes of archaeal origin associated with corals. Multiple DNA samples drawn from nine coral species and four different reef locations were PCR screened for archaeal and bacterial amoA genes, and archaeal amoA gene sequences were obtained from five different species of coral coll...

  6. [Bacterial and archaeal diversity in surface sediment from the south slope of the South China Sea].

    Science.gov (United States)

    Li, Tao; Wang, Peng; Wang, Pinxian

    2008-03-01

    Diversity of bacteria and archaea was studied in deep marine sediments by PCR amplification and sequence analysis of 16S rDNA. Sample analysed was from IMAGES (International Marine Past Global Change Study) 147 at site of the south slope of the South China Sea. DNA was amplified from samples at the surface layer of core MD05-2896. Phylogenetic analysis of clone libraries showed a wide variety of uncultured bacteria and archeae. The most abundant bacterial sequences (phylotypes) corresponded to the Proteobacteria, followed by the Planctomycete, Acidobacteria and candidate division OP10. Phylotypes ascribing to Deferrobacteres, Verrucomicrobia, Spirochaetes and candidate division clades of OP3, OP11, OP8 and TM6 were also identified. Archaeal 16S rDNA sequences were within phylums of Crenarchaeota and Euryarchaeota, respectively. The majority of archaeal phylotypes were Marine Benthic Group B (MBGB), Marine Crenarchaeotic Group I (MG I), Marine Benthic Group D (MBGD) and South African Gold Mine Euryarchaeotic Group (SAGMEG). Additional sequences grouped with the C3, Methanobacteriales and Novel Euryarchaeotic Group (NEG). These results indicate that bacteria and archaea are abundant and diversified in surface environment of subseafloor sediments. PMID:18479058

  7. RNA-Based Assessment of Diversity and Composition of Active Archaeal Communities in the German Bight

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    Bernd Wemheuer

    2012-01-01

    Full Text Available Archaea play an important role in various biogeochemical cycles. They are known extremophiles inhabiting environments such as thermal springs or hydrothermal vents. Recent studies have revealed a significant abundance of Archaea in moderate environments, for example, temperate sea water. Nevertheless, the composition and ecosystem function of these marine archaeal communities is largely unknown. To assess diversity and composition of active archaeal communities in the German Bight, seven marine water samples were taken and studied by RNA-based analysis of ribosomal 16S rRNA. For this purpose, total RNA was extracted from the samples and converted to cDNA. Archaeal community structures were investigated by pyrosequencing-based analysis of 16S rRNA amplicons generated from cDNA. To our knowledge, this is the first study combining next-generation sequencing and metatranscriptomics to study archaeal communities in marine habitats. The pyrosequencing-derived dataset comprised 62,045 archaeal 16S rRNA sequences. We identified Halobacteria as the predominant archaeal group across all samples with increased abundance in algal blooms. Thermoplasmatales (Euryarchaeota and the Marine Group I (Thaumarchaeota were identified in minor abundances. It is indicated that archaeal community patterns were influenced by environmental conditions.

  8. A Meta-Analysis of the Bacterial and Archaeal Diversity Observed in Wetland Soils

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    Xiaofei Lv

    2014-01-01

    Full Text Available This study examined the bacterial and archaeal diversity from a worldwide range of wetlands soils and sediments using a meta-analysis approach. All available 16S rRNA gene sequences recovered from wetlands in public databases were retrieved. In November 2012, a total of 12677 bacterial and 1747 archaeal sequences were collected in GenBank. All the bacterial sequences were assigned into 6383 operational taxonomic units (OTUs 0.03, representing 31 known bacterial phyla, predominant with Proteobacteria (2791 OTUs, Bacteroidetes (868 OTUs, Acidobacteria (731 OTUs, Firmicutes (540 OTUs, and Actinobacteria (418 OTUs. The genus Flavobacterium (11.6% of bacterial sequences was the dominate bacteria in wetlands, followed by Gp1, Nitrosospira, and Nitrosomonas. Archaeal sequences were assigned to 521 OTUs from phyla Euryarchaeota and Crenarchaeota. The dominating archaeal genera were Fervidicoccus and Methanosaeta. Rarefaction analysis indicated that approximately 40% of bacterial and 83% of archaeal diversity in wetland soils and sediments have been presented. Our results should be significant for well-understanding the microbial diversity involved in worldwide wetlands.

  9. Biosynthesis of ribose-5-phosphate and erythrose-4-phosphate in archaea: a phylogenetic analysis of archaeal genomes

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    Tim Soderberg

    2005-01-01

    Full Text Available A phylogenetic analysis of the genes encoding enzymes in the pentose phosphate pathway (PPP, the ribulose monophosphate (RuMP pathway, and the chorismate pathway of aromatic amino acid biosynthesis, employing data from 13 complete archaeal genomes, provides a potential explanation for the enigmatic phylogenetic patterns of the PPP genes in archaea. Genomic and biochemical evidence suggests that three archaeal species (Methanocaldococcus jannaschii, Thermoplasma acidophilum and Thermoplasma volcanium produce ribose-5-phosphate via the nonoxidative PPP (NOPPP, whereas nine species apparently lack an NOPPP but may employ a reverse RuMP pathway for pentose synthesis. One species (Halobacterium sp. NRC-1 lacks both the NOPPP and the RuMP pathway but may possess a modified oxidative PPP (OPPP, the details of which are not yet known. The presence of transketolase in several archaeal species that are missing the other two NOPPP genes can be explained by the existence of differing requirements for erythrose-4-phosphate (E4P among archaea: six species use transketolase to make E4P as a precursor to aromatic amino acids, six species apparently have an alternate biosynthetic pathway and may not require the ability to make E4P, and one species (Pyrococcus horikoshii probably does not synthesize aromatic amino acids at all.

  10. Diversity and Habitat Niche Modeling of Candidate Archaeal Phylum Aigarchaeota

    Science.gov (United States)

    Alba, T. W.; Goertz, G.; Williams, A. J.; Cole, J. K.; Murugapiran, S. K.; Dodsworth, J. A.; Hedlund, B. P.

    2013-12-01

    ';Aigarchaeota' (formerly known as pSL4 and Hot Water Crenarchaeotic Group I (HWCGI)) is a candidate phylum of Archaea known only by 16S rRNA gene fragments from cultivation-independent microbial surveys and a single composite genome from Candidatus ';Caldiarchaeum subterraneum', an inhabitant of a subterranean gold mine in Japan. Sequences reported in various publications are found exclusively in geothermal settings, but a comprehensive assessment has not yet been performed. We mined public databases for 16S rRNA gene sequences related to known ';Aigarchaeota' and used a combination of approaches to rigorously define the phylogenetic boundaries of the phylum. The analyses supported the proposed relationship between ';Aigarchaeota', Thaumarchaeota, Crenarchaeota, and Korarchaeota in the so-called 'TACK superphylum' and identified ~200 16S rRNA genes and gene fragments belonging to ';Aigarchaeota', including those recovered from terrestrial geothermal systems on several continents (North America, Asia, Africa, Europe, and Oceania) and marine geothermal and subsurface samples in both the Atlantic and Pacific. ';Aigarchaeota' belonged to at least three family- to order-level groups and at least seven genus-level groups. All genus-level groups were recovered from geographically distant locations, suggesting a global distribution within amenable habitats. ';Aigarchaeota'-specific primers for the polymerase chain reaction (PCR) amplification of 16S rRNA genes were designed using SP-Designer and reviewed using the Ribosomal Database Project Probe Match tool. The primers will be used to determine the presence and abundance of ';Aigarchaeota' in a wide variety of samples from terrestrial geothermal systems in the western U.S. and Asia. These phylogenetic data, along with a large geochemical database, will be analyzed using multivariate statistics to develop biogeographic and habitat niche models for ';Aigarchaeota'. This study offers the first coherent view of the

  11. Phylogenetic diversity of Mesorhizobium in chickpea

    Indian Academy of Sciences (India)

    Dong Hyun Kim; Mayank Kaashyap; Abhishek Rathore; Roma R Das; Swathi Parupalli; Hari D Upadhyaya; S Gopalakrishnan; Pooran M Gaur; Sarvjeet Singh; Jagmeet Kaur; Mohammad Yasin; Rajeev K Varshney

    2014-06-01

    Crop domestication, in general, has reduced genetic diversity in cultivated gene pool of chickpea (Cicer arietinum) as compared with wild species (C. reticulatum, C. bijugum). To explore impact of domestication on symbiosis, 10 accessions of chickpeas, including 4 accessions of C. arietinum, and 3 accessions of each of C. reticulatum and C. bijugum species, were selected and DNAs were extracted from their nodules. To distinguish chickpea symbiont, preliminary sequences analysis was attempted with 9 genes (16S rRNA, atpD, dnaJ, glnA, gyrB, nifH, nifK, nodD and recA) of which 3 genes (gyrB, nifK and nodD) were selected based on sufficient sequence diversity for further phylogenetic analysis. Phylogenetic analysis and sequence diversity for 3 genes demonstrated that sequences from C. reticulatum were more diverse. Nodule occupancy by dominant symbiont also indicated that C. reticulatum (60%) could have more various symbionts than cultivated chickpea (80%). The study demonstrated that wild chickpeas (C. reticulatum) could be used for selecting more diverse symbionts in the field conditions and it implies that chickpea domestication affected symbiosis negatively in addition to reducing genetic diversity.

  12. Archaeal viruses of the sulfolobales

    DEFF Research Database (Denmark)

    Erdmann, Susanne; Garrett, Roger Antony

    2015-01-01

    Infection of archaea with phylogenetically diverse single viruses, performed in different laboratories, has failed to activate spacer acquisition into host CRISPR loci. The first successful uptake of archaeal de novo spacers was observed on infection of Sulfolobus solfataricus P2 with an environm......Infection of archaea with phylogenetically diverse single viruses, performed in different laboratories, has failed to activate spacer acquisition into host CRISPR loci. The first successful uptake of archaeal de novo spacers was observed on infection of Sulfolobus solfataricus P2 with an...... CRISPR loci of Sulfolobus species from a second coinfecting conjugative plasmid or virus (Erdmann and Garrett, Mol Microbiol 85:1044-1056, 2012; Erdmann et al. Mol Microbiol 91:900-917, 2014). Here we describe, firstly, the isolation of archaeal virus mixtures from terrestrial hot springs and the...

  13. Phylogenetic and functional analysis of metagenome sequence from high-temperature archaeal habitats demonstrate linkages between metabolic potential and geochemistry

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    William P. Inskeep

    2013-05-01

    Full Text Available Geothermal habitats in Yellowstone National Park (YNP provide an unparalled opportunity to understand the environmental factors that control the distribution of archaea in thermal habitats. Here we describe, analyze and synthesize metagenomic and geochemical data collected from seven high-temperature sites that contain microbial communities dominated by archaea relative to bacteria. The specific objectives of the study were to use metagenome sequencing to determine the structure and functional capacity of thermophilic archaeal-dominated microbial communities across a pH range from 2.5 to 6.4 and to discuss specific examples where the metabolic potential correlated with measured environmental parameters and geochemical processes occurring in situ. Random shotgun metagenome sequence (~40-45 Mbase Sanger sequencing per site was obtained from environmental DNA extracted from high-temperature sediments and/or microbial mats and subjected to numerous phylogenetic and functional analyses. Analysis of individual sequences (e.g., MEGAN and G+C content and assemblies from each habitat type revealed the presence of dominant archaeal populations in all environments, 10 of whose genomes were largely reconstructed from the sequence data. Analysis of protein family occurrence, particularly of those involved in energy conservation, electron transport and autotrophic metabolism, revealed significant differences in metabolic strategies across sites consistent with differences in major geochemical attributes (e.g., sulfide, oxygen, pH. These observations provide an ecological basis for understanding the distribution of indigenous archaeal lineages across high temperature systems of YNP.

  14. Quantitative and phylogenetic study of the Deep Sea Archaeal Group in sediments of the arctic mid-ocean spreading ridge

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    Steffen LethJørgensen

    2013-10-01

    Full Text Available In marine sediments archaea often constitute a considerable part of the microbial community, of which the Deep Sea Archaeal Group (DSAG is one of the most predominant. Despite their high abundance no members from this archaeal group have so far been characterized and thus their metabolism is unknown. Here we show that the relative abundance of DSAG marker genes can be correlated with geochemical parameters, allowing prediction of both the potential electron donors and acceptors of these organisms. We estimated the abundance of 16S rRNA genes from Archaea, Bacteria and DSAG in 52 sediment horizons from two cores collected at the slow-spreading Arctic Mid-Ocean Ridge, using qPCR. The results indicate that members of the DSAG make up the entire archaeal population in certain horizons and constitute up to ~ 50% of the total microbial community. The quantitative data were correlated to 30 different geophysical and geochemical parameters obtained from the same sediment horizons. We observed a significant correlation between the relative abundance of DSAG 16S rRNA genes and the content of organic carbon (p < 0.0001. Further, significant co-variation with iron oxide, and dissolved iron and manganese (all p < 0.0000, indicated a direct or indirect link to iron and manganese cycling. Neither of these parameters correlated with the relative abundance of archaeal or bacterial 16S rRNA genes, nor did any other major electron donor or acceptor measured. Phylogenetic analysis of DSAG 16S rRNA gene sequences reveals three monophyletic lineages with no apparent habitat-specific distribution. In this study we support the hypothesis that members of the DSAG are tightly linked to the content of organic carbon and directly or indirectly involved in the cycling of iron and/or manganese compounds. Further, we provide a molecular tool to assess their abundance in environmental samples and enrichment cultures.

  15. Fast Computations for Measures of Phylogenetic Beta Diversity

    OpenAIRE

    Tsirogiannis, Constantinos; Sandel, Brody

    2016-01-01

    For many applications in ecology, it is important to examine the phylogenetic relations between two communities of species. More formally, let T be a phylogenetic tree and let A and B be two samples of its tips, representing the examined communities. We want to compute a value that expresses the phylogenetic diversity between A and B in T . There exist several measures that can do this; these are the so-called phylogenetic beta diversity (β-diversity) measures. Two popular measures of this ki...

  16. Diversity and Abundance of Ammonia-Oxidizing Archaeal Nitrite Reductase (nirK) Genes in Estuarine Sediments of San Francisco Bay

    Science.gov (United States)

    Reji, L.; Lee, J. A.; Damashek, J.; Francis, C. A.

    2013-12-01

    Nitrification, the microbially-mediated aerobic oxidation of ammonia to nitrate via nitrite, is an integral component of the global biogeochemical nitrogen cycle. The first and rate-limiting step of nitrification, ammonia oxidation, is carried out by two distinct microbial groups: ammonia-oxidizing bacteria (AOB) and ammonia-oxidizing archaea (AOA). Molecular ecological studies targeting the amoA gene have revealed the abundance and ubiquity of AOA in terrestrial as well as aquatic environments. In addition to the ammonia oxidation machinery that includes the amoA gene, AOA also encode a gene for copper-containing nitrite reductase (nirK). The distribution patterns and functional role of nirK in AOA remain mostly unknown; proposed functions include the indirect involvement in ammonia oxidation through the production of nitric oxide during nitrite reduction, and (2) nitrite detoxification. In the present study, the diversity and abundance of archaeal nirK genes in estuarine sediments were investigated using quantitative polymerase chain reaction, cloning and sequencing approaches. In sediment samples collected from the San Francisco Bay estuary, two archaeal nirK variants (AnirKa and AnirKb) were amplified using specific primer sets. Overall, AnirKa was observed to be significantly more abundant than AnirKb in the sediment samples, with variation in relative abundance spanning two to three orders of magnitude between sampling sites. Phylogenetic analysis revealed a number of unique archaeal nirK sequence types, as well as many that clustered with sequences from previous estuarine studies and cultured AOA isolates, such as Nitrosopumilus maritimus. This study yielded new insights into the diversity and abundance of archaeal nirK genes in estuarine sediments, and highlights the importance of further investigating the physiological role of this gene in AOA, as well as its suitability as a marker gene for studying AOA in the environment.

  17. Diversity of putative archaeal RNA viruses in metagenomic datasets of a yellowstone acidic hot spring.

    OpenAIRE

    Hongming WANG; Yu, Yongxin; Liu, Taigang; Pan, Yingjie; Yan, Shuling; Wang, Yongjie

    2015-01-01

    Two genomic fragments (5,662 and 1,269 nt in size, GenBank accession no. JQ756122 and JQ756123, respectively) of novel, positive-strand RNA viruses that infect archaea were first discovered in an acidic hot spring in Yellowstone National Park (Bolduc et al., 2012). To investigate the diversity of these newly identified putative archaeal RNA viruses, global metagenomic datasets were searched for sequences that were significantly similar to those of the viruses. A total of 3,757 associated read...

  18. Bacterial and Archaeal Diversity in the Gastrointestinal Tract of the North American Beaver (Castor canadensis)

    Science.gov (United States)

    Gruninger, Robert J.; McAllister, Tim A.; Forster, Robert J.

    2016-01-01

    The North American Beaver (Castor canadensis) is the second largest living rodent and an iconic symbol of Canada. The beaver is a semi-aquatic browser whose diet consists of lignocellulose from a variety of plants. The beaver is a hindgut fermenter and has an enlarged ceacum that houses a complex microbiome. There have been few studies examining the microbial diversity in gastrointestinal tract of hindgut fermenting herbivores. To examine the bacterial and archaeal communities inhabiting the gastrointestinal tract of the beaver, the microbiome of the ceacum and feaces was examined using culture-independent methods. DNA from the microbial community of the ceacum and feaces of 4 adult beavers was extracted, and the16S rRNA gene was sequenced using either bacterial or archaeal specific primers. A total of 1447 and 1435 unique bacterial OTUs were sequenced from the ceacum and feaces, respectively. On average, the majority of OTUs within the ceacum were classified as Bacteroidetes (49.2%) and Firmicutes (47.6%). The feaces was also dominated by OTUs from Bacteroidetes (36.8%) and Firmicutes (58.9%). The composition of bacterial community was not significantly different among animals. The composition of the ceacal and feacal microbiome differed, but this difference is due to changes in the abundance of closely related OTUs, not because of major differences in the taxonomic composition of the communities. Within these communities, known degraders of lignocellulose were identified. In contrast, to the bacterial microbiome, the archaeal community was dominated by a single species of methanogen, Methanosphaera stadtmanae. The data presented here provide the first insight into the microbial community within the hindgut of the beaver. PMID:27227334

  19. Phylogenetic analysis of bacterial and archaeal arsC gene sequences suggests an ancient, common origin for arsenate reductase

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    Dugas Sandra L

    2003-07-01

    Full Text Available Abstract Background The ars gene system provides arsenic resistance for a variety of microorganisms and can be chromosomal or plasmid-borne. The arsC gene, which codes for an arsenate reductase is essential for arsenate resistance and transforms arsenate into arsenite, which is extruded from the cell. A survey of GenBank shows that arsC appears to be phylogenetically widespread both in organisms with known arsenic resistance and those organisms that have been sequenced as part of whole genome projects. Results Phylogenetic analysis of aligned arsC sequences shows broad similarities to the established 16S rRNA phylogeny, with separation of bacterial, archaeal, and subsequently eukaryotic arsC genes. However, inconsistencies between arsC and 16S rRNA are apparent for some taxa. Cyanobacteria and some of the γ-Proteobacteria appear to possess arsC genes that are similar to those of Low GC Gram-positive Bacteria, and other isolated taxa possess arsC genes that would not be expected based on known evolutionary relationships. There is no clear separation of plasmid-borne and chromosomal arsC genes, although a number of the Enterobacteriales (γ-Proteobacteria possess similar plasmid-encoded arsC sequences. Conclusion The overall phylogeny of the arsenate reductases suggests a single, early origin of the arsC gene and subsequent sequence divergence to give the distinct arsC classes that exist today. Discrepancies between 16S rRNA and arsC phylogenies support the role of horizontal gene transfer (HGT in the evolution of arsenate reductases, with a number of instances of HGT early in bacterial arsC evolution. Plasmid-borne arsC genes are not monophyletic suggesting multiple cases of chromosomal-plasmid exchange and subsequent HGT. Overall, arsC phylogeny is complex and is likely the result of a number of evolutionary mechanisms.

  20. Archaeal amoA gene diversity points to distinct biogeography of ammonia-oxidizing Crenarchaeota in the ocean

    NARCIS (Netherlands)

    Sintes, Eva; Bergauer, Kristin; De Corte, Daniele; Yokokawa, Taichi; Herndl, Gerhard J.

    2013-01-01

    Mesophilic ammonia-oxidizing Archaea (AOA) are abundant in a diverse range of marine environments, including the deep ocean, as revealed by the quantification of the archaeal amoA gene encoding the alpha-subunit of the ammonia monooxygenase. Using two different amoA primer sets, two distinct ecotype

  1. Functionally and phylogenetically diverse plant communities key to soil biota

    OpenAIRE

    Milcu, Alexandru; Allan, Eric; Roscher, Christiane; Jenkins, Tania; Meyer, Sebastian T.; Flynn, Dan; Bessler, Holger; Buscot, François; Engels, Christof; Gubsch, Marlén; König, Stephan; Lipowsky, Annett; Loranger, Jessy; Renker, Carsten; Scherber, Christoph

    2013-01-01

    Recent studies assessing the role of biological diversity for ecosystem functioning indicate that the diversity of functional traits and the evolutionary history of species in a community, not the number of taxonomic units, ultimately drives the biodiversity–ecosystem-function relationship. Here, we simultaneously assessed the importance of plant functional trait and phylogenetic diversity as predictors of major trophic groups of soil biota (abundance and diversity), six years from the onset ...

  2. Phylogenetic diversity (PD and biodiversity conservation: some bioinformatics challenges

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    Daniel P. Faith

    2006-01-01

    Full Text Available Biodiversity conservation addresses information challenges through estimations encapsulated in measures of diversity. A quantitative measure of phylogenetic diversity, “PD”, has been defined as the minimum total length of all the phylogenetic branches required to span a given set of taxa on the phylogenetic tree (Faith 1992a. While a recent paper incorrectly characterizes PD as not including information about deeper phylogenetic branches, PD applications over the past decade document the proper incorporation of shared deep branches when assessing the total PD of a set of taxa. Current PD applications to macroinvertebrate taxa in streams of New South Wales, Australia illustrate the practical importance of this definition. Phylogenetic lineages, often corresponding to new, “cryptic”, taxa, are restricted to a small number of stream localities. A recent case of human impact causing loss of taxa in one locality implies a higher PD value for another locality, because it now uniquely represents a deeper branch. This molecular-based phylogenetic pattern supports the use of DNA barcoding programs for biodiversity conservation planning. Here, PD assessments side-step the contentious use of barcoding-based “species” designations. Bio-informatics challenges include combining different phylogenetic evidence, optimization problems for conservation planning, and effective integration of phylogenetic information with environmental and socio-economic data.

  3. Archaeal community in a human-disturbed watershed in southeast China: diversity, distribution, and responses to environmental changes.

    Science.gov (United States)

    Hu, Anyi; Wang, Hongjie; Li, Jiangwei; Liu, Jing; Chen, Nengwang; Yu, Chang-Ping

    2016-05-01

    The response of freshwater bacterial community to anthropogenic disturbance has been well documented, yet the studies of freshwater archaeal community are rare, especially in lotic environments. Here, we investigated planktonic and benthic archaeal communities in a human-perturbed watershed (Jiulong River Watershed, JRW) of southeast China by using Illumina 16S ribosomal RNA gene amplicon sequencing. The results of taxonomic assignments indicated that SAGMGC-1, Methanobacteriaceae, Methanospirillaceae, and Methanoregulaceae were the four most abundant families in surface waters, accounting for 12.65, 23.21, 18.58 and 10.97 % of planktonic communities, whereas Nitrososphaeraceae and Miscellaneous Crenarchaeotic Group occupied more than 49 % of benthic communities. The compositions of archaeal communities and populations in waters and sediments were significantly different from each other. Remarkably, the detection frequencies of families Methanobacteriaceae and Methanospirillaceae, and genera Methanobrevibacter and Methanosphaera in planktonic communities correlated strongly with bacterial fecal indicator, suggesting some parts of methanogenic Archaea may come from fecal contamination. Because soluble reactive phosphorus (SRP) and the ratio of dissolved inorganic nitrogen to SRP instead of nitrogen nutrients showed significant correlation with several planktonic Nitrosopumilus- and Nitrosotalea-like OTUs, Thaumarchaeota may play an unexplored role in biogeochemical cycling of river phosphorus. Multivariate statistical analyses revealed that the variation of α-diversity of planktonic archaeal community was best explained by water temperature, whereas nutrient concentrations and stoichiometry were the significant drivers of β-diversity of planktonic and benthic communities. Taken together, these results demonstrate that the structure of archaeal communities in the JRW is sensitive to anthropogenic disturbances caused by riparian human activities. PMID:26810199

  4. Phylogenetic and biological species diversity within the Neurospora tetrasperma complex.

    Science.gov (United States)

    Menkis, A; Bastiaans, E; Jacobson, D J; Johannesson, H

    2009-09-01

    The objective of this study was to explore the evolutionary history of the morphologically recognized filamentous ascomycete Neurospora tetrasperma, and to reveal the genetic and reproductive relationships among its individuals and populations. We applied both phylogenetic and biological species recognition to a collection of strains representing the geographic and genetic diversity of N. tetrasperma. First, we were able to confirm a monophyletic origin of N. tetrasperma. Furthermore, we found nine phylogenetic species within the morphospecies. When using the traditional broad biological species recognition all investigated strains of N. tetrasperma constituted a single biological species. In contrast, when using a quantitative measurement of the reproductive success, incorporating characters such as viability and fertility of offspring, we found a high congruence between the phylogenetic and biological species recognition. Taken together, phylogenetically and biologically defined groups of individuals exist in N. tetrasperma, and these should be taken into account in future studies of its life history traits. PMID:19682307

  5. Microbial population, activity, and phylogenetic diversity in the subseafloor core sediment from the Sea of Okhotsk

    Science.gov (United States)

    Inagaki, F.; Suzuki, M.; Takai, K.; Nealson, K. H.; Horikoshi, K.

    2002-12-01

    Subseafloor environments has already been recognized as the largest biosphere on the planet Earth, however, the microbial diversity and activity has been still poorly understood, even in their impacts on biogeochemical processes, tectonic settings, and paleoenvironmental events. We demonstrate here the evaluation of microbial community structure and active habitats in deeply buried cold marine sediments collected from the Sea of Okhotsk by a combined use of molecular ecological surveys and culturing assays. The piston core sediment (MD01-2412) was collected by IMAGES (International Marine Global Change Study) Project from the southeastern Okhotsk Sea, June 2001. The total recovered length was about 58m. The lithology of the core sediment was mainly constructed from pelagic clay (PC) and volcanic ash layers (Ash). We collected aseptically the most inside core parts from 16 sections at different depths for microbiological study. The direct count of DAPI-stained cells revealed that the cells in Ash samples were present 1.2 to 2.2 times higher than in PC samples. The quantitative-PCR of 16S rDNA between bacterial and archaeal rDNA suggested that the increased population density in Ash layers was caused by the bacterial components. We studied approximately 650 and 550 sequences from bacterial and archaeal rDNA clone libraries, respectively. The similarity and phylogenetic analyses revealed that the microbial community structures were apparently different between in Ash layers and PC samples. From bacterial rDNA clone libraries, the members within gamma-Proteobacteria such as genera Halomonas, Shewanella, Psychromonas and Methylosinus were predominantly detected in Ash layers whereas the Dehalococcoides group and delta-Proteobacteria were major bacterial components in PC samples. From archaeal libraries, the sequences from Ash and PC samples were affiliated into the clusters represented by the environmental sequences obtained from terrestrial and deep-sea environments

  6. Diversity of Archaeal Consortia in an Arsenic-Rich Hydrothermal System

    Science.gov (United States)

    Franks, M.; Bennett, P.; Omelon, C.; Engel, A.

    2008-12-01

    Characterizing microbial communities within their geochemical environment is essential to understanding microbial distribution and microbial adaptations to extreme physical and chemical conditions. The hydrothermal waters at El Tatio geyser field demonstrate extreme conditions, with water at local boiling (85°C), arsenic concentrations at 0.5 mM, and inorganic carbon concentrations as low as 0.02mM. Yet many of El Tatio's hundred plus hydrothermal features are associated with extensive microbial mat communities. Recent work has shown phylogenetic variation in the communities that correlates to variations in water chemistry between features. MPN analysis indicates variations in metabolic function between hydrothermal features, such as the ability of the community to fix nitrogen, and the presence of methanogens within the community. Methanogenic archaea, which are typical of hydrothermal environments, are found in very few of the sampled hydrothermal features at El Tatio. MPN enumeration shows that nonspecific microbial mat samples from sites with dissolved methane contain 106 cells of methanogenic archaea per gram while non-specific samples from sites lacking dissolved methane contain 100 cells per gram or less. An acetylene assay showed evidence for nitrogen fixation in a sample associated with methanogenesis, but microbial transformation of acetylene to ethylene did not occur in non-methanogenic sites. More specific sampling of microbial mats indicates that methanogenic archaea are dominated by microorganisms within the genus Methanospirillum and Methanobrevibacter. These microbes are associated with a number of unclassified archaea in the class Thermoplasmata Halobacteriales, and unclassifiec Crenarchaeota. In addition, preliminary results include an unclassified Thaumarchaeota clone, a member of the recently proposed third archaeal phylum Thaumarchaeota. Nonspecific microbial mat sample from a non- methanogenic site included only Crenarchaeal clones within the

  7. Land-Sparing Agriculture Best Protects Avian Phylogenetic Diversity.

    Science.gov (United States)

    Edwards, David P; Gilroy, James J; Thomas, Gavin H; Uribe, Claudia A Medina; Haugaasen, Torbjørn

    2015-09-21

    The conversion of natural habitats to farmland is a major driver of the global extinction crisis. Two strategies are promoted to mitigate the impacts of agricultural expansion on biodiversity: land sharing integrates wildlife-friendly habitats within farmland landscapes, and land sparing intensifies farming to allow the offset of natural reserves. A key question is which strategy would protect the most phylogenetic diversity--the total evolutionary history shared across all species within a community. Conserving phylogenetic diversity decreases the chance of losing unique phenotypic and ecological traits and provides benefits for ecosystem function and stability. Focusing on birds in the threatened Chocó-Andes hotspot of endemism, we tested the relative benefits of each strategy for retaining phylogenetic diversity in tropical cloud forest landscapes threatened by cattle pastures. Using landscape simulations, we find that land sharing would protect lower community-level phylogenetic diversity than land sparing and that with increasing distance from forest (from 500 to >1,500 m), land sharing is increasingly inferior to land sparing. Isolation from forest also leads to the loss of more evolutionarily distinct species from communities within land-sharing landscapes, which can be avoided with effective land sparing. Land-sharing policies that promote the integration of small-scale wildlife-friendly habitats might be of limited benefit without the simultaneous protection of larger blocks of natural habitat, which is most likely to be achieved via land-sparing measures. PMID:26344093

  8. Lipase production by diverse phylogenetic clades of Aureobasidium pullulans

    Science.gov (United States)

    Thirty-nine strains representing 12 diverse phylogenetic clades of Aureobasidium pullulans were surveyed for lipase production using a quantitative assay. Strains in clades 4 and 10 produced 0.2-0.3 U lipase/ml, while color variant strain NRRL Y-2311-1 in clade 8 produced 0.54 U lipase/ml. Strains i...

  9. Spatial Patterns of Palm Diversity from a Phylogenetic Perspective

    DEFF Research Database (Denmark)

    Eiserhardt, Wolf L.; Svenning, J.-C.; Kissling, W. Daniel;

    With ~2,500 species and a Pantropical distribution, the palm family (Arecaceae) has emerged as an important model taxon for studies of tropical plant diversity. In a recent review we showed that palm species distributions, species composition, and species richness depend on ecological factors at....... Robust and well-resolved phylogenetic trees, in combination with comprehensive distributional and trait data, can provide important insights into the long-term causes of spatial biodiversity patterns. Palms lend themselves to such research not least due to an exceptionally good data basis, and several...... studies using a variety of approaches have recently shown that the distribution of palm diversity is strongly influenced by the phylogenetic history of the family. Here, we provide an overview of evidence for evolutionary imprints on palm diversity patterns (sensu lato), including our own studies where we...

  10. Host specialization and phylogenetic diversity of Corynespora cassiicola.

    Science.gov (United States)

    Dixon, L J; Schlub, R L; Pernezny, K; Datnoff, L E

    2009-09-01

    The fungus Corynespora cassiicola is primarily found in the tropics and subtropics, and is widely diverse in substrate utilization and host association. Isolate characterization within C. cassiicola was undertaken to investigate how genetic diversity correlates with host specificity, growth rate, and geographic distribution. C. cassiicola isolates were collected from 68 different plant species in American Samoa, Brazil, Malaysia, and Micronesia, and Florida, Mississippi, and Tennessee within the United States. Phylogenetic analyses using four loci were performed with 143 Corynespora spp. isolates, including outgroup taxa obtained from culture collections: C. citricola, C. melongenae, C. olivacea, C. proliferata, C. sesamum, and C. smithii. Phylogenetic trees were congruent from the ribosomal DNA internal transcribed spacer region, two random hypervariable loci (caa5 and ga4), and the actin-encoding locus act1, indicating a lack of recombination within the species and asexual propagation. Fifty isolates were tested for pathogenicity on eight known C. cassiicola crop hosts: basil, bean, cowpea, cucumber, papaya, soybean, sweet potato, and tomato. Pathogenicity profiles ranged from one to four hosts, with cucumber appearing in 14 of the 16 profiles. Bootstrap analyses and Bayesian posterior probability values identified six statistically significant phylogenetic lineages. The six phylogenetic lineages correlated with host of origin, pathogenicity, and growth rate but not with geographic location. Common fungal genotypes were widely distributed geographically, indicating long-distance and global dispersal of clonal lineages. This research reveals an abundance of previously unrecognized genetic diversity within the species and provides evidence for host specialization on papaya. PMID:19671003

  11. Altitudinal Patterns of Species Diversity and Phylogenetic Diversity across Temperate Mountain Forests of Northern China

    Science.gov (United States)

    Zhang, Wenxin; Huang, Dizhou; Wang, Renqing; Liu, Jian; Du, Ning

    2016-01-01

    The spatial patterns of biodiversity and their underlying mechanisms have been an active area of research for a long time. In this study, a total of 63 samples (20m × 30m) were systematically established along elevation gradients on Mount Tai and Mount Lao, China. We explored altitudinal patterns of plant diversity in the two mountain systems. In order to understand the mechanisms driving current diversity patterns, we used phylogenetic approaches to detect the spatial patterns of phylogenetic diversity and phylogenetic structure along two elevation gradients. We found that total species richness had a monotonically decreasing pattern and tree richness had a unimodal pattern along the elevation gradients in the two study areas. However, altitudinal patterns in shrub richness and herbs richness were not consistent on the two mountains. At low elevation, anthropogenic disturbances contributed to the increase of plant diversity, especially for shrubs and herbs in understory layers, which are more sensitive to changes in microenvironment. The phylogenetic structure of plant communities exhibited an inverted hump-shaped pattern along the elevation gradient on Mount Tai, which demonstrates that environmental filtering is the main driver of plant community assembly at high and low elevations and inter-specific competition may be the main driver of plant community assembly in the middle elevations. However, the phylogenetic structure of plant communities did not display a clear pattern on Mount Lao where the climate is milder. Phylogenetic beta diversity and species beta diversity consistently increased with increasing altitudinal divergence in the two study areas. However, the altitudinal patterns of species richness did not completely mirror phylogenetic diversity patterns. Conservation areas should be selected taking into consideration the preservation of high species richness, while maximizing phylogenetic diversity to improve the potential for diversification in the

  12. Understanding global patterns of mammalian functional and phylogenetic diversity

    Science.gov (United States)

    Safi, Kamran; Cianciaruso, Marcus V.; Loyola, Rafael D.; Brito, Daniel; Armour-Marshall, Katrina; Diniz-Filho, José Alexandre F.

    2011-01-01

    Documenting and exploring the patterns of diversity of life on Earth has always been a central theme in biology. Species richness despite being the most commonly used measure of diversity in macroecological studies suffers from not considering the evolutionary and ecological differences among species. Phylogenetic diversity (PD) and functional diversity (FD) have been proposed as alternative measures to overcome this limitation. Although species richness, PD and FD are closely related, their relationships have never been investigated on a global scale. Comparing PD and FD with species richness corroborated the general assumptions of surrogacy of the different diversity measures. However, the analysis of the residual variance suggested that the mismatches between the diversity measures are influenced by environmental conditions. PD increased relative to species richness with increasing mean annual temperature, whereas FD decreased with decreasing seasonality relative to PD. We also show that the tropical areas are characterized by a FD deficit, a phenomenon, that suggests that in tropical areas more species can be packed into the ecological space. We discuss potential mechanisms that could have resulted in the gradient of spatial mismatch observed in the different biodiversity measures and draw parallels to local scale studies. We conclude that the use of multiple diversity measures on a global scale can help to elucidate the relative importance of historical and ecological processes shaping the present gradients in mammalian diversity. PMID:21807734

  13. Panorama phylogenetic diversity and distribution of Type A influenza virus.

    Directory of Open Access Journals (Sweden)

    Shuo Liu

    Full Text Available BACKGROUND: Type A influenza virus is one of important pathogens of various animals, including humans, pigs, horses, marine mammals and birds. Currently, the viral type has been classified into 16 hemagglutinin and 9 neuraminidase subtypes, but the phylogenetic diversity and distribution within the viral type largely remain unclear from the whole view. METHODOLOGY/PRINCIPAL FINDINGS: The panorama phylogenetic trees of influenza A viruses were calculated with representative sequences selected from approximately 23,000 candidates available in GenBank using web servers in NCBI and the software MEGA 4.0. Lineages and sublineages were classified according to genetic distances, topology of the phylogenetic trees and distributions of the viruses in hosts, regions and time. CONCLUSIONS/SIGNIFICANCE: Here, two panorama phylogenetic trees of type A influenza virus covering all the 16 hemagglutinin subtypes and 9 neuraminidase subtypes, respectively, were generated. The trees provided us whole views and some novel information to recognize influenza A viruses including that some subtypes of avian influenza viruses are more complicated than Eurasian and North American lineages as we thought in the past. They also provide us a framework to generalize the history and explore the future of the viral circulation and evolution in different kinds of hosts. In addition, a simple and comprehensive nomenclature system for the dozens of lineages and sublineages identified within the viral type was proposed, which if universally accepted, will facilitate communications on the viral evolution, ecology and epidemiology.

  14. Archaeal amoA gene diversity points to distinct biogeography of ammonia-oxidizing Crenarchaeota in the ocean

    OpenAIRE

    Sintes, Eva; Bergauer, Kristin; de Corte, Daniele; Yokokawa, Taichi; Herndl, Gerhard J.

    2013-01-01

    Mesophilic ammonia-oxidizing Archaea (AOA) are abundant in a diverse range of marine environments, including the deep ocean, as revealed by the quantification of the archaeal amoA gene encoding the alpha-subunit of the ammonia monooxygenase. Using two different amoA primer sets, two distinct ecotypes of marine Crenarchaeota Group I (MCGI) were detected in the waters of the tropical Atlantic and the coastal Arctic. The HAC-AOA ecotype (high ammonia concentration AOA) was ≍ 8000 times and 15 ti...

  15. The climatic niche diversity of malagasy primates: a phylogenetic perspective.

    Directory of Open Access Journals (Sweden)

    Jason M Kamilar

    Full Text Available BACKGROUND: Numerous researchers have posited that there should be a strong negative relationship between the evolutionary distance among species and their ecological similarity. Alternative evidence suggests that members of adaptive radiations should display no relationship between divergence time and ecological similarity because rapid evolution results in near-simultaneous speciation early in the clade's history. In this paper, we performed the first investigation of ecological diversity in a phylogenetic context using a mammalian adaptive radiation, the Malagasy primates. METHODOLOGY/PRINCIPAL FINDINGS: We collected data for 43 extant species including: 1 1064 species by locality samples, 2 GIS climate data for each sampling locality, and 3 the phylogenetic relationships of the species. We calculated the niche space of each species by summarizing the climatic variation at localities of known occurrence. Climate data from all species occurrences at all sites were entered into a principal components analysis. We calculated the mean value of the first two PCA axes, representing rainfall and temperature diversity, for each species. We calculated the K statistic using the Physig program for Matlab to examine how well the climatic niche space of species was correlated with phylogeny. CONCLUSIONS/SIGNIFICANCE: We found that there was little relationship between the phylogenetic distance of Malagasy primates and their rainfall and temperature niche space, i.e., closely related species tend to occupy different climatic niches. Furthermore, several species from different genera converged on a similar climatic niche. These results have important implications for the evolution of ecological diversity, and the long-term survival of these endangered species.

  16. Phylogenetic and Functional Analysis of Metagenome Sequence from High-Temperature Archaeal Habitats Demonstrate Linkages between Metabolic Potential and Geochemistry

    DEFF Research Database (Denmark)

    Inskeep, William P; Jay, Zackary J; Herrgard, Markus;

    2013-01-01

    Geothermal habitats in Yellowstone National Park (YNP) provide an unparalleled opportunity to understand the environmental factors that control the distribution of archaea in thermal habitats. Here we describe, analyze, and synthesize metagenomic and geochemical data collected from seven high......-temperature sites that contain microbial communities dominated by archaea relative to bacteria. The specific objectives of the study were to use metagenome sequencing to determine the structure and functional capacity of thermophilic archaeal-dominated microbial communities across a pH range from 2.5 to 6.......4 and to discuss specific examples where the metabolic potential correlated with measured environmental parameters and geochemical processes occurring in situ. Random shotgun metagenome sequence (∼40-45 Mb Sanger sequencing per site) was obtained from environmental DNA extracted from high-temperature sediments and...

  17. A molecular phylogenetic analysis of strombid gastropod morphological diversity.

    Science.gov (United States)

    Latiolais, Jared M; Taylor, Michael S; Roy, Kaustuv; Hellberg, Michael E

    2006-11-01

    The shells of strombid gastropods show a wide variety of forms, ranging from small and fusiform to large and elaborately ornamented with a strongly flared outer lip. Here, we present the first species-level molecular phylogeny for strombids and use the resulting phylogenetic framework to explore relationships between species richness and morphological diversity. We use portions of one nuclear (325 bp of histone H3) and one mitochondrial (640 bp of cytochrome oxidase I, COI) gene to infer relationships within the two most species-rich genera in the Strombidae: Strombus and Lambis. We include 32 species of Strombus, representing 10 of 11 extant subgenera, and 3 of the 9 species of Lambis, representing 2 of 3 extant subgenera. Maximum likelihood and Bayesian analyses of COI and of H3 and COI combined suggest Lambis is nested within a paraphyletic Strombus. Eastern Pacific and western Atlantic species of Strombus form a relatively recent monophyletic radiation within an older, paraphyletic Indo-West Pacific grade. Morphological diversity of subclades scales positively with species richness but does not show evidence of strong phylogenetic constraints. PMID:16839783

  18. Phylogenetic Diversity and Spatial Distribution of the Microbial Community Associated with the Caribbean Deep-water Sponge Polymastia cf. corticata by 16S rRNA, aprA, and amoA Gene Analysis

    OpenAIRE

    Meyer, Birte; Kuever, Jan

    2008-01-01

    Denaturing gradient gel electrophoresis (DGGE)-based analyses of 16S rRNA, aprA, and amoA genes demonstrated that a phylogenetically diverse and complex microbial community was associated with the Caribbean deep-water sponge Polymastia cf. corticata Ridley and Dendy, 1887. From the 38 archaeal and bacterial 16S rRNA phylotypes identified, 53% branched into the sponge-specific, monophyletic sequence clusters determined by previous studies (considering predominantly shallow-water sponge species...

  19. Functional and phylogenetic diversity of woody plants drive herbivory in a highly diverse forest

    OpenAIRE

    Schuldt, Andreas; Assmann, Thorsten; Bruelheide, Helge; Durka, Walter; Eichenberg, David; Härdtle, Werner; Kröber, Wenzel; Michalski, Stefan G.; Purschke, Oliver

    2014-01-01

    Biodiversity loss may alter ecosystem processes, such as herbivory, a key driver of ecological functions in species-rich (sub)tropical forests. However, the mechanisms underlying such biodiversity effects remain poorly explored, as mostly effects of species richness – a very basic biodiversity measure – have been studied. Here, we analyze to what extent the functional and phylogenetic diversity of woody plant communities affect herbivory along a diversity gradient in a subtropical forest. We ...

  20. Archaeal diversity in a Fe-As rich acid mine drainage at Carnoules (France)

    OpenAIRE

    Bruneel, Odile; Pascault, N.; Egal, M; Bancon-Montigny, C.; Goni-urriza, M. S.; Elbaz Poulichet, F.; Personne, J. C.; Duran, R.

    2008-01-01

    The acid waters (pH = 2.73-3.4) that originate from the Carnoules mine tailings (France) are known for their very high concentrations of As (up to 10,000 mg l(-1)) and Fe (up to 20,000 mg l(-1)). To analyze the composition of the archaeal community, (their temporal variation inside the tailing and spatial variations all along the Reigous Creek, which drains the site), seven 16S rRNA gene libraries were constructed. Clone analysis revealed that all the sequences were affiliated to the phylum E...

  1. Characteristics of phylogenetic diversity in airborne bacterial populations in China

    Science.gov (United States)

    Chaudhry, Zahra; Santarpia, Joshua L.; Martins, J. V.

    2011-05-01

    Considering their potential implications for human health, agricultural productivity, and ecosystem stability, surprisingly little is known about the composition or dynamics of the atmosphere's biological aerosols. The few studies that have examined phylogenetic diversity in China focused on a single sampling period, whereas this study spans 3 months and includes over 300 samples. The 300+ samples were categorized by month and direction of their back-trajectory. DNA extraction was carried out on the pooled samples in a quantitative manner to allow for comparison between the amount of extracted material and the amount of initial total aerosol mass. Within an individual month, samples originating from similar land types and approximately equidistant to the sampling location exhibited similar diversity, whereas samples originating from much greater distances and from different land types included phyla unique to that location. Phyla from the same origin also varied from one month to the next. The biological diversity found from the Phylochips reinforces the hypothesis that air samples carry a biological record of their history.

  2. Phylogenetic and functional alpha and beta diversity in temperate and tropical tree communities

    OpenAIRE

    Nathan G Swenson; Erikson, David L.; Mi, Xiangcheng; Norman A. Bourg; Forero-Montaña, Jimena; Ge, Xuejun; Howe, Robert; Lake, Jeffrey K.; Liu, Xiaojuan; Ma, Keping; Pei, Nancai; Thompson, Jill; Uriarte, Maria; Wolf, Amy; Wright, S. Joseph

    2012-01-01

    The study of biodiversity has tended to focus primarily on relatively information poor measures of species diversity. Recently, many studies of local diversity (alpha diversity) have begun to use measures of functional and phylogenetic alpha diversity. Investigations into the phylogenetic and functional dissimilarity (beta diversity) of communities have been far less numerous, but these dissimilarity measures have the potential to infer the mechanisms underlying community assembly and dynamic...

  3. A database of phylogenetically atypical genes in archaeal and bacterial genomes, identified using the DarkHorse algorithm

    Directory of Open Access Journals (Sweden)

    Allen Eric E

    2008-10-01

    Full Text Available Abstract Background The process of horizontal gene transfer (HGT is believed to be widespread in Bacteria and Archaea, but little comparative data is available addressing its occurrence in complete microbial genomes. Collection of high-quality, automated HGT prediction data based on phylogenetic evidence has previously been impractical for large numbers of genomes at once, due to prohibitive computational demands. DarkHorse, a recently described statistical method for discovering phylogenetically atypical genes on a genome-wide basis, provides a means to solve this problem through lineage probability index (LPI ranking scores. LPI scores inversely reflect phylogenetic distance between a test amino acid sequence and its closest available database matches. Proteins with low LPI scores are good horizontal gene transfer candidates; those with high scores are not. Description The DarkHorse algorithm has been applied to 955 microbial genome sequences, and the results organized into a web-searchable relational database, called the DarkHorse HGT Candidate Resource http://darkhorse.ucsd.edu. Users can select individual genomes or groups of genomes to screen by LPI score, search for protein functions by descriptive annotation or amino acid sequence similarity, or select proteins with unusual G+C composition in their underlying coding sequences. The search engine reports LPI scores for match partners as well as query sequences, providing the opportunity to explore whether potential HGT donor sequences are phylogenetically typical or atypical within their own genomes. This information can be used to predict whether or not sufficient information is available to build a well-supported phylogenetic tree using the potential donor sequence. Conclusion The DarkHorse HGT Candidate database provides a powerful, flexible set of tools for identifying phylogenetically atypical proteins, allowing researchers to explore both individual HGT events in single genomes, and

  4. Prokaryotic Caspase Homologs: Phylogenetic Patterns and Functional Characteristics Reveal Considerable Diversity

    Science.gov (United States)

    Asplund-Samuelsson, Johannes; Bergman, Birgitta; Larsson, John

    2012-01-01

    Caspases accomplish initiation and execution of apoptosis, a programmed cell death process specific to metazoans. The existence of prokaryotic caspase homologs, termed metacaspases, has been known for slightly more than a decade. Despite their potential connection to the evolution of programmed cell death in eukaryotes, the phylogenetic distribution and functions of these prokaryotic metacaspase sequences are largely uncharted, while a few experiments imply involvement in programmed cell death. Aiming at providing a more detailed picture of prokaryotic caspase homologs, we applied a computational approach based on Hidden Markov Model search profiles to identify and functionally characterize putative metacaspases in bacterial and archaeal genomes. Out of the total of 1463 analyzed genomes, merely 267 (18%) were identified to contain putative metacaspases, but their taxonomic distribution included most prokaryotic phyla and a few archaea (Euryarchaeota). Metacaspases were particularly abundant in Alphaproteobacteria, Deltaproteobacteria and Cyanobacteria, which harbor many morphologically and developmentally complex organisms, and a distinct correlation was found between abundance and phenotypic complexity in Cyanobacteria. Notably, Bacillus subtilis and Escherichia coli, known to undergo genetically regulated autolysis, lacked metacaspases. Pfam domain architecture analysis combined with operon identification revealed rich and varied configurations among the metacaspase sequences. These imply roles in programmed cell death, but also e.g. in signaling, various enzymatic activities and protein modification. Together our data show a wide and scattered distribution of caspase homologs in prokaryotes with structurally and functionally diverse sub-groups, and with a potentially intriguing evolutionary role. These features will help delineate future characterizations of death pathways in prokaryotes. PMID:23185476

  5. Does Land-Use Intensification Decrease Plant Phylogenetic Diversity in Local Grasslands?

    OpenAIRE

    Egorov, Eugen; Prati, Daniel; Durka, Walter; Michalski, Stefan; Fischer, Markus; Schmitt, Barbara; Blaser, Stefan; Braendle, Martin

    2014-01-01

    Phylogenetic diversity (PD) has been successfully used as a complement to classical measures of biological diversity such as species richness or functional diversity. By considering the phylogenetic history of species, PD broadly summarizes the trait space within a community. This covers amongst others complex physiological or biochemical traits that are often not considered in estimates of functional diversity, but may be important for the understanding of community assembly and the relation...

  6. Archaeal diversity and the extent of iron and manganese pyritization in sediments from a tropical mangrove creek (Cardoso Island, Brazil)

    Science.gov (United States)

    Otero, X. L.; Lucheta, A. R.; Ferreira, T. O.; Huerta-Díaz, M. A.; Lambais, M. R.

    2014-06-01

    Even though several studies on the geochemical processes occurring in mangrove soils and sediments have been performed, information on the diversity of Archaea and their functional roles in these ecosystems, especially in subsurface environments, is scarce. In this study, we have analyzed the depth distribution of Archaea and their possible relationships with the geochemical transformations of Fe and Mn in a sediment core from a tropical mangrove creek, using 16S rRNA gene profiling and sequential extraction of different forms of Fe and Mn. A significant shift in the archaeal community structure was observed in the lower layers (90-100 cm), coinciding with a clear decrease in total organic carbon (TOC) content and an increase in the percentage of sand. The comparison of the archaeal communities showed a dominance of methanogenic Euryarchaeota in the upper layers (0-20 cm), whereas Crenarchaeota was the most abundant taxon in the lower layers. The dominance of methanogenic Euryarchaeota in the upper layer of the sediment suggests the occurrence of methanogenesis in anoxic microenvironments. The concentrations of Fe-oxyhydroxides in the profile were very low, and showed positive correlation with the concentrations of pyrite and degrees of Fe and Mn pyritization. Additionally, a partial decoupling of pyrite formation from organic matter concentration was observed, suggesting excessive Fe pyritization. This overpyritization of Fe can be explained either by the anoxic oxidation of methane by sulfate and/or by detrital pyrite tidal transportation from the surrounding mangrove soils. The higher pyritization levels observed in deeper layers of the creek sediment were also in agreement with its Pleistocenic origin.

  7. Phylogenetic diversity and position of the genus Campylobacter

    Science.gov (United States)

    Lau, P. P.; DeBrunner-Vossbrinck, B.; Dunn, B.; Miotto, K.; MacDonnell, M. T.; Rollins, D. M.; Pillidge, C. J.; Hespell, R. B.; Colwell, R. R.; Sogin, M. L.; Fox, G. E.

    1987-01-01

    RNA sequence analysis has been used to examine the phylogenetic position and structure of the genus Campylobacter. A complete 5S rRNA sequence was determined for two strains of Campylobacter jejuni and extensive partial sequences of the 16S rRNA were obtained for several strains of C. jejuni and Wolinella succinogenes. In addition limited partial sequence data were obtained from the 16S rRNAs of isolates of C. coli, C. laridis, C. fetus, C. fecalis, and C. pyloridis. It was found that W. succinogenes is specifically related to, but not included, in the genus Campylobacter as presently constituted. Within the genus significant diversity was noted. C. jejuni, C. coli and C. laridis are very closely related but the other species are distinctly different from one another. C. pyloridis is without question the most divergent of the Campylobacter isolates examined here and is sufficiently distinct to warrant inclusion in a separate genus. In terms of overall position in bacterial phylogeny, the Campylobacter/Wolinella cluster represents a deep branching most probably located within an expanded version of the Division containing the purple photosynthetic bacteria and their relatives. The Campylobacter/Wolinella cluster is not specifically includable in either the alpha, beta or gamma subdivisions of the purple bacteria.

  8. Structure and diversity of bacterial, eukaryotic and archaeal communities in glacial cryoconite holes from the Arctic and the Antarctic.

    Science.gov (United States)

    Cameron, Karen A; Hodson, Andrew J; Osborn, A Mark

    2012-11-01

    The cryosphere presents some of the most challenging conditions for life on earth. Nevertheless, (micro)biota survive in a range of niches in glacial systems, including water-filled depressions on glacial surfaces termed cryoconite holes (centimetre to metre in diameter and up to 0.5 m deep) that contain dark granular material (cryoconite). In this study, the structure of bacterial and eukaryotic cryoconite communities from ten different locations in the Arctic and Antarctica was compared using T-RFLP analysis of rRNA genes. Community structure varied with geography, with greatest differences seen between communities from the Arctic and the Antarctic. DNA sequencing of rRNA genes revealed considerable diversity, with individual cryoconite hole communities containing between six and eight bacterial phyla and five and eight eukaryotic 'first-rank' taxa and including both bacterial and eukaryotic photoautotrophs. Bacterial Firmicutes and Deltaproteobacteria and Epsilonproteobacteria, eukaryotic Rhizaria, Haptophyta, Choanomonada and Centroheliozoa, and archaea were identified for the first time in cryoconite ecosystems. Archaea were only found within Antarctic locations, with the majority of sequences (77%) related to members of the Thaumarchaeota. In conclusion, this research has revealed that Antarctic and Arctic cryoconite holes harbour geographically distinct highly diverse communities and has identified hitherto unknown bacterial, eukaryotic and archaeal taxa, therein. PMID:22168226

  9. Phylogenetic beta diversity in tropical forests: Implications for the roles of geographical and environmental distance

    Institute of Scientific and Technical Information of China (English)

    Jin-Long ZHANG; Nathan G.SWENSON; Sheng-Bin CHEN; Xiao-Juan LIU; Zong-Shan LI; Ji-Hong HUANG; Xiang-Cheng MI

    2013-01-01

    Various mechanistic theories of community assembly have been proposed ranging from niche-based theory to neutral theory.Analyses of beta diversity in a phylogenetic context could provide an excellent opportunity for testing many of these hypotheses.We analyzed the patterns of phylogenetic beta diversity in tropical tree communities in Panama to test several community assembly hypotheses.In particular,the degree to which the phylogenetic dissimilarity between communities can be explained by geographical or environmental distance can yield support for stochastic or deterministic assembly processes,respectively.Therefore,we examined:(i) the existence of distance decay of phylogenetic similarity among communities and its degree of departure from that expected under a null model; and (ii) the relative importance of geographical versus environmental distance in predicting the phylogenetic dissimilarity of communities.We found evidence that the similarity in the phylogenetic composition of communities decayed with geographical distance and environmental gradients.Null model evidence showed that beta diversity in the study system was phylogenetically non-random.Our results highlighted not only the role of local ecological mechanisms,including environmental filtering and competitive exclusion,but also biogeographical processes such as speciation,dispersal limitation,and niche evolution in structuring phylogenetic turnover.These results also highlight the importance of niche conservatism in structuring species diversity patterns.

  10. Edge-related loss of tree phylogenetic diversity in the severely fragmented Brazilian Atlantic forest.

    Directory of Open Access Journals (Sweden)

    Bráulio A Santos

    Full Text Available Deforestation and forest fragmentation are known major causes of nonrandom extinction, but there is no information about their impact on the phylogenetic diversity of the remaining species assemblages. Using a large vegetation dataset from an old hyper-fragmented landscape in the Brazilian Atlantic rainforest we assess whether the local extirpation of tree species and functional impoverishment of tree assemblages reduce the phylogenetic diversity of the remaining tree assemblages. We detected a significant loss of tree phylogenetic diversity in forest edges, but not in core areas of small (<80 ha forest fragments. This was attributed to a reduction of 11% in the average phylogenetic distance between any two randomly chosen individuals from forest edges; an increase of 17% in the average phylogenetic distance to closest non-conspecific relative for each individual in forest edges; and to the potential manifestation of late edge effects in the core areas of small forest remnants. We found no evidence supporting fragmentation-induced phylogenetic clustering or evenness. This could be explained by the low phylogenetic conservatism of key life-history traits corresponding to vulnerable species. Edge effects must be reduced to effectively protect tree phylogenetic diversity in the severely fragmented Brazilian Atlantic forest.

  11. Using phylogenetic, functional and trait diversity to understand patterns of plant community productivity.

    Directory of Open Access Journals (Sweden)

    Marc W Cadotte

    Full Text Available BACKGROUND: Two decades of research showing that increasing plant diversity results in greater community productivity has been predicated on greater functional diversity allowing access to more of the total available resources. Thus, understanding phenotypic attributes that allow species to partition resources is fundamentally important to explaining diversity-productivity relationships. METHODOLOGY/PRINCIPAL FINDINGS: Here we use data from a long-term experiment (Cedar Creek, MN and compare the extent to which productivity is explained by seven types of community metrics of functional variation: 1 species richness, 2 variation in 10 individual traits, 3 functional group richness, 4 a distance-based measure of functional diversity, 5 a hierarchical multivariate clustering method, 6 a nonmetric multidimensional scaling approach, and 7 a phylogenetic diversity measure, summing phylogenetic branch lengths connecting community members together and may be a surrogate for ecological differences. Although most of these diversity measures provided significant explanations of variation in productivity, the presence of a nitrogen fixer and phylogenetic diversity were the two best explanatory variables. Further, a statistical model that included the presence of a nitrogen fixer, seed weight and phylogenetic diversity was a better explanation of community productivity than other models. CONCLUSIONS: Evolutionary relationships among species appear to explain patterns of grassland productivity. Further, these results reveal that functional differences among species involve a complex suite of traits and that perhaps phylogenetic relationships provide a better measure of the diversity among species that contributes to productivity than individual or small groups of traits.

  12. Archaeal and bacterial diversity in an arsenic-rich shallow-sea hydrothermal system undergoing phase separation

    Directory of Open Access Journals (Sweden)

    Roy Edward Price

    2013-07-01

    Full Text Available Phase separation is a ubiquitous process in seafloor hydrothermal vents, creating a large range of salinities. Toxic elements (e.g., arsenic partition into the vapor phase, and thus can be enriched in both high and low salinity fluids. However, investigations of microbial diversity at sites associated with phase separation are rare. We evaluated prokaryotic diversity in arsenic-rich shallow-sea vents off Milos Island (Greece by comparative analysis of 16S rRNA clone sequences from two vent sites with similar pH and temperature but marked differences in salinity. Clone sequences were also obtained for aioA-like functional genes (AFGs. Bacteria in the surface sediments (0 to 1.5 cm at the high salinity site consisted of mainly Epsilonproteobacteria (Arcobacter sp., which transitioned to almost exclusively Firmicutes (Bacillus sp. at ~10 cm depth. However, the low salinity site consisted of Bacteroidetes (Flavobacteria in the surface and Epsilonproteobacteria (Arcobacter sp. at ~10 cm depth. Archaea in the high salinity surface sediments were dominated by the orders Archaeoglobales and Thermococcales, transitioning to Thermoproteales and Desulfurococcales (Staphylothermus sp. in the deeper sediments. In contrast, the low salinity site was dominated by Thermoplasmatales in the surface and Thermoproteales at depth. Similarities in gas and redox chemistry suggest that salinity and/or arsenic concentrations may select for microbial communities that can tolerate these parameters. Many of the archaeal 16S rRNA sequences contained inserts, possibly introns, including members of the Euryarchaeota. Clones containing AFGs affiliated with either Alpha- or Betaproteobacteria, although most were only distantly related to published representatives. Most clones (89% originated from the deeper layer of the low salinity, highest arsenic site. This is the only sample with overlap in 16S rRNA data, suggesting arsenotrophy as an important metabolism in similar

  13. Phylogenetic and Metabolic Diversity of Planctomycetes from Anaerobic, Sulfide- and Sulfur-Rich Zodletone Spring, Oklahoma▿

    OpenAIRE

    Elshahed, Mostafa S.; Youssef, Noha H.; Luo, Qingwei; Najar, Fares Z; Roe, Bruce A; Sisk, Tracy M.; Bühring, Solveig I.; Hinrichs, Kai-Uwe; Krumholz, Lee R

    2007-01-01

    We investigated the phylogenetic diversity and metabolic capabilities of members of the phylum Planctomycetes in the anaerobic, sulfide-saturated sediments of a mesophilic spring (Zodletone Spring) in southwestern Oklahoma. Culture-independent analyses of 16S rRNA gene sequences generated using Planctomycetes-biased primer pairs suggested that an extremely diverse community of Planctomycetes is present at the spring. Although sequences that are phylogenetically affiliated with cultured hetero...

  14. Land-use systems affect Archaeal community structure and functional diversity in western Amazon soils

    OpenAIRE

    Acácio Aparecido Navarrete; Rodrigo Gouvêa Taketani; Lucas William Mendes; Fabiana de Souza Cannavan; Fatima Maria de Souza Moreira; Siu Mui Tsai

    2011-01-01

    The study of the ecology of soil microbial communities at relevant spatial scales is primordial in the wide Amazon region due to the current land use changes. In this study, the diversity of the Archaea domain (community structure) and ammonia-oxidizing Archaea (richness and community composition) were investigated using molecular biology-based techniques in different land-use systems in western Amazonia, Brazil. Soil samples were collected in two periods with high precipitation (March 2008 a...

  15. Distribution and Diversity of Archaeal and Bacterial Ammonia Oxidizers in Salt Marsh Sediments▿

    OpenAIRE

    Moin, Nicole S.; Nelson, Katelyn A.; Bush, Alexander; Bernhard, Anne E.

    2009-01-01

    Diversity and abundance of ammonia-oxidizing Betaproteobacteria (β-AOB) and archaea (AOA) were investigated in a New England salt marsh at sites dominated by short or tall Spartina alterniflora (SAS and SAT sites, respectively) or Spartina patens (SP site). AOA amoA gene richness was higher than β-AOB amoA richness at SAT and SP, but AOA and β-AOB richness were similar at SAS. β-AOB amoA clone libraries were composed exclusively of Nitrosospira-like amoA genes. AOA amoA genes at SAT and SP we...

  16. Abundance and Diversity of Bacterial, Archaeal, and Fungal Communities Along an Altitudinal Gradient in Alpine Forest Soils: What Are the Driving Factors?

    Science.gov (United States)

    Siles, José A; Margesin, Rosa

    2016-07-01

    Shifts in soil microbial communities over altitudinal gradients and the driving factors are poorly studied. Their elucidation is indispensable to gain a comprehensive understanding of the response of ecosystems to global climate change. Here, we investigated soil archaeal, bacterial, and fungal communities at four Alpine forest sites representing a climosequence, over an altitudinal gradient from 545 to 2000 m above sea level (asl), regarding abundance and diversity by using qPCR and Illumina sequencing, respectively. Archaeal community was dominated by Thaumarchaeota, and no significant shifts were detected in abundance or community composition with altitude. The relative bacterial abundance increased at higher altitudes, which was related to increasing levels of soil organic matter and nutrients with altitude. Shifts in bacterial richness and diversity as well as community structure (comprised basically of Proteobacteria, Acidobacteria, Actinobacteria, and Bacteroidetes) significantly correlated with several environmental and soil chemical factors, especially soil pH. The site at the lowest altitude harbored the highest bacterial richness and diversity, although richness/diversity community properties did not show a monotonic decrease along the gradient. The relative size of fungal community also increased with altitude and its composition comprised Ascomycota, Basidiomycota, and Zygomycota. Changes in fungal richness/diversity and community structure were mainly governed by pH and C/N, respectively. The variation of the predominant bacterial and fungal classes over the altitudinal gradient was the result of the environmental and soil chemical factors prevailing at each site. PMID:26961712

  17. Nitrogen addition, not initial phylogenetic diversity, increases litter decomposition by fungal communities

    Directory of Open Access Journals (Sweden)

    Anthony Stuart Amend

    2015-02-01

    Full Text Available Fungi play a critical role in the degradation of organic matter. Because different combinations of fungi result in different rates of decomposition, determining how climate change will affect microbial composition and function is fundamental to predicting future environments. Fungal response to global change is patterned by genetic relatedness, resulting in communities with comparatively low phylogenetic diversity. This may have important implications for the functional capacity of disturbed communities if lineages sensitive to disturbance also contain unique traits important for litter decomposition. Here we tested the relationship between phylogenetic diversity and decomposition rates. Leaf litter fungi were isolated from the field and deployed in microcosms as mock communities along a gradient of initial phylogenetic diversity, while species richness was held constant. Replicate communities were subject to nitrogen fertilization comparable to anthropogenic deposition levels. Carbon mineralization rates were measured over the course of sixty-six days. We found that nitrogen fertilization increased cumulative respiration by 24.8%, and that differences in respiration between fertilized and ambient communities diminished over the course of the experiment. Initial phylogenetic diversity failed to predict respiration rates or their change in response to nitrogen fertilization, and there was no correlation between community similarity and respiration rates. Last, we detected no phylogenetic signal in the contributions of individual isolates to respiration rates. Our results suggest that the degree to which phylogenetic diversity predicts ecosystem function will depend on environmental context.

  18. Yersinia pestis genome sequencing identifies patterns of global phylogenetic diversity.

    Science.gov (United States)

    Morelli, Giovanna; Song, Yajun; Mazzoni, Camila J; Eppinger, Mark; Roumagnac, Philippe; Wagner, David M; Feldkamp, Mirjam; Kusecek, Barica; Vogler, Amy J; Li, Yanjun; Cui, Yujun; Thomson, Nicholas R; Jombart, Thibaut; Leblois, Raphael; Lichtner, Peter; Rahalison, Lila; Petersen, Jeannine M; Balloux, Francois; Keim, Paul; Wirth, Thierry; Ravel, Jacques; Yang, Ruifu; Carniel, Elisabeth; Achtman, Mark

    2010-12-01

    Plague is a pandemic human invasive disease caused by the bacterial agent Yersinia pestis. We here report a comparison of 17 whole genomes of Y. pestis isolates from global sources. We also screened a global collection of 286 Y. pestis isolates for 933 SNPs using Sequenom MassArray SNP typing. We conducted phylogenetic analyses on this sequence variation dataset, assigned isolates to populations based on maximum parsimony and, from these results, made inferences regarding historical transmission routes. Our phylogenetic analysis suggests that Y. pestis evolved in or near China and spread through multiple radiations to Europe, South America, Africa and Southeast Asia, leading to country-specific lineages that can be traced by lineage-specific SNPs. All 626 current isolates from the United States reflect one radiation, and 82 isolates from Madagascar represent a second radiation. Subsequent local microevolution of Y. pestis is marked by sequential, geographically specific SNPs. PMID:21037571

  19. Yersinia pestis genome sequencing identifies patterns of global phylogenetic diversity.

    OpenAIRE

    Morelli, Giovanna; Song, Yajun; Mazzoni, Camila J.; Eppinger, Mark; Roumagnac, Philippe; Wagner, David M.; Feldkamp, Mirjam; Kusecek, Barica; Vogler, Amy J.; Li, Yanjun; Cui, Yujun; Thomson, Nicholas R.; Jombart, Thibaut; Leblois, Raphael; Lichtner, Peter

    2010-01-01

    Plague is a pandemic human invasive disease caused by the bacterial agent Yersinia pestis. We here report a comparison of 17 whole genomes of Y. pestis isolates from global sources. We also screened a global collection of 286 Y. pestis isolates for 933 SNPs using Sequenom MassArray SNP typing. We conducted phylogenetic analyses on this sequence variation dataset, assigned isolates to populations based on maximum parsimony and, from these results, made inferences regarding historical transmiss...

  20. Phylogenetic diversity does not capture body size variation at risk in the world's mammals

    DEFF Research Database (Denmark)

    Fritz, Susanne A; Purvis, Andy

    2010-01-01

    Mammals contribute to important ecosystem processes and services, but many mammalian species are threatened with extinction. We compare how global patterns in three measures of mammalian diversity--species richness, phylogenetic diversity (PD) and body mass variance (BMV)--would change if all cur...

  1. Phylogenetic Diversity in the Macromolecular Composition of Microalgae

    Science.gov (United States)

    Finkel, Zoe V.; Follows, Mick J.; Liefer, Justin D.; Brown, Chris M.; Benner, Ina; Irwin, Andrew J.

    2016-01-01

    The elemental stoichiometry of microalgae reflects their underlying macromolecular composition and influences competitive interactions among species and their role in the food web and biogeochemistry. Here we provide a new estimate of the macromolecular composition of microalgae using a hierarchical Bayesian analysis of data compiled from the literature. The median macromolecular composition of nutrient-sufficient exponentially growing microalgae is 32.2% protein, 17.3% lipid, 15.0% carbohydrate, 17.3% ash, 5.7% RNA, 1.1% chlorophyll-a and 1.0% DNA as percent dry weight. Our analysis identifies significant phylogenetic differences in macromolecular composition undetected by previous studies due to small sample sizes and the large inherent variability in macromolecular pools. The phylogenetic differences in macromolecular composition lead to variations in carbon-to-nitrogen ratios that are consistent with independent observations. These phylogenetic differences in macromolecular and elemental composition reflect adaptations in cellular architecture and biochemistry; specifically in the cell wall, the light harvesting apparatus, and storage pools. PMID:27228080

  2. Phylogenetics.

    Science.gov (United States)

    Sleator, Roy D

    2011-04-01

    The recent rapid expansion in the DNA and protein databases, arising from large-scale genomic and metagenomic sequence projects, has forced significant development in the field of phylogenetics: the study of the evolutionary relatedness of the planet's inhabitants. Advances in phylogenetic analysis have greatly transformed our view of the landscape of evolutionary biology, transcending the view of the tree of life that has shaped evolutionary theory since Darwinian times. Indeed, modern phylogenetic analysis no longer focuses on the restricted Darwinian-Mendelian model of vertical gene transfer, but must also consider the significant degree of lateral gene transfer, which connects and shapes almost all living things. Herein, I review the major tree-building methods, their strengths, weaknesses and future prospects. PMID:21249334

  3. Archaeal Communities in a Heterogeneous Hypersaline-Alkaline Soil

    Directory of Open Access Journals (Sweden)

    Yendi E. Navarro-Noya

    2015-01-01

    Full Text Available In this study the archaeal communities in extreme saline-alkaline soils of the former lake Texcoco, Mexico, with electrolytic conductivities (EC ranging from 0.7 to 157.2 dS/m and pH from 8.5 to 10.5 were explored. Archaeal communities in the 0.7 dS/m pH 8.5 soil had the lowest alpha diversity values and were dominated by a limited number of phylotypes belonging to the mesophilic Candidatus Nitrososphaera. Diversity and species richness were higher in the soils with EC between 9.0 and 157.2 dS/m. The majority of OTUs detected in the hypersaline soil were members of the Halobacteriaceae family. Novel phylogenetic branches in the Halobacteriales class were detected in the soil, and more abundantly in soil with the higher pH (10.5, indicating that unknown and uncharacterized Archaea can be found in this soil. Thirteen different genera of the Halobacteriaceae family were identified and were distributed differently between the soils. Halobiforma, Halostagnicola, Haloterrigena, and Natronomonas were found in all soil samples. Methanogenic archaea were found only in soil with pH between 10.0 and 10.3. Retrieved methanogenic archaea belonged to the Methanosarcinales and Methanomicrobiales orders. The comparison of the archaeal community structures considering phylogenetic information (UniFrac distances clearly clustered the communities by pH.

  4. Archaeal virus-host interactions

    OpenAIRE

    Quax, T.E.F.

    2013-01-01

      The work presented in this thesis provides novel insights in several aspects of the molecular biology of archaea, bacteria and their viruses. Three fundamentally different groups of viruses are associated with the three domains of life. Archaeal viruses are characterized by a particularly high morphological and genetic diversity. Some archaeal viruses, such as Sulfolobus islandicus rod-shaped virus 2 (SIRV2), have quite remarkable infection cycles. As described in Chapter 1, infection ...

  5. Metagenomic-Based Study of the Phylogenetic and Functional Gene Diversity in Galápagos Land and Marine Iguanas

    KAUST Repository

    Hong, Pei-Ying

    2014-12-19

    In this study, a metagenome-based analysis of the fecal samples from the macrophytic algae-consuming marine iguana (MI; Amblyrhynchus cristatus) and terrestrial biomass-consuming land iguanas (LI; Conolophus spp.) was conducted. Phylogenetic affiliations of the fecal microbiome were more similar between both iguanas than to other mammalian herbivorous hosts. However, functional gene diversities in both MI and LI iguana hosts differed in relation to the diet, where the MI fecal microbiota had a functional diversity that clustered apart from the other terrestrial-biomass consuming reptilian and mammalian hosts. A further examination of the carbohydrate-degrading genes revealed that several of the prevalent glycosyl hydrolases (GH), glycosyl transferases (GT), carbohydrate binding modules (CBM), and carbohydrate esterases (CE) gene classes were conserved among all examined herbivorous hosts, reiterating the important roles these genes play in the breakdown and metabolism of herbivorous diets. Genes encoding some classes of carbohydrate-degrading families, including GH2, GH13, GT2, GT4, CBM50, CBM48, CE4, and CE11, as well as genes associated with sulfur metabolism and dehalogenation, were highly enriched or unique to the MI. In contrast, gene sequences that relate to archaeal methanogenesis were detected only in LI fecal microbiome, and genes coding for GH13, GH66, GT2, GT4, CBM50, CBM13, CE4, and CE8 carbohydrate active enzymes were highly abundant in the LI. Bacterial populations were enriched on various carbohydrates substrates (e.g., glucose, arabinose, xylose). The majority of the enriched bacterial populations belong to genera Clostridium spp. and Enterococcus spp. that likely accounted for the high prevalence of GH13 and GH2, as well as the GT families (e.g., GT2, GT4, GT28, GT35, and GT51) that were ubiquitously present in the fecal microbiota of all herbivorous hosts.

  6. Metagenomic-based study of the phylogenetic and functional gene diversity in Galápagos land and marine iguanas.

    Science.gov (United States)

    Hong, Pei-Ying; Mao, Yuejian; Ortiz-Kofoed, Shannon; Shah, Rushabh; Cann, Isaac; Mackie, Roderick I

    2015-02-01

    In this study, a metagenome-based analysis of the fecal samples from the macrophytic algae-consuming marine iguana (MI; Amblyrhynchus cristatus) and terrestrial biomass-consuming land iguanas (LI; Conolophus spp.) was conducted. Phylogenetic affiliations of the fecal microbiome were more similar between both iguanas than to other mammalian herbivorous hosts. However, functional gene diversities in both MI and LI iguana hosts differed in relation to the diet, where the MI fecal microbiota had a functional diversity that clustered apart from the other terrestrial-biomass consuming reptilian and mammalian hosts. A further examination of the carbohydrate-degrading genes revealed that several of the prevalent glycosyl hydrolases (GH), glycosyl transferases (GT), carbohydrate binding modules (CBM), and carbohydrate esterases (CE) gene classes were conserved among all examined herbivorous hosts, reiterating the important roles these genes play in the breakdown and metabolism of herbivorous diets. Genes encoding some classes of carbohydrate-degrading families, including GH2, GH13, GT2, GT4, CBM50, CBM48, CE4, and CE11, as well as genes associated with sulfur metabolism and dehalogenation, were highly enriched or unique to the MI. In contrast, gene sequences that relate to archaeal methanogenesis were detected only in LI fecal microbiome, and genes coding for GH13, GH66, GT2, GT4, CBM50, CBM13, CE4, and CE8 carbohydrate active enzymes were highly abundant in the LI. Bacterial populations were enriched on various carbohydrates substrates (e.g., glucose, arabinose, xylose). The majority of the enriched bacterial populations belong to genera Clostridium spp. and Enterococcus spp. that likely accounted for the high prevalence of GH13 and GH2, as well as the GT families (e.g., GT2, GT4, GT28, GT35, and GT51) that were ubiquitously present in the fecal microbiota of all herbivorous hosts. PMID:25524569

  7. Human-mediated loss of phylogenetic and functional diversity in coral reef fishes

    OpenAIRE

    D'Agata, S.; Mouillot, D.; Kulbicki, Michel; Andréfouët, Serge; Bellwood, D. R.; Cinner, J. E.; Cowman, P. F.; Kronen, M.; Pinca, S.; Vigliola, Laurent

    2014-01-01

    Beyond the loss of species richness [1-3], human activities may also deplete the breadth of evolutionary history (phylogenetic diversity) and the diversity of roles (functional diversity) carried out by species within communities, two overlooked components of biodiversity. Both are, however, essential to sustain ecosystem functioning and the associated provision of ecosystem services, particularly under fluctuating environmental conditions [1-7]. We quantified the effect of human activities o...

  8. Plant-Pollinator Coextinctions and the Loss of Plant Functional and Phylogenetic Diversity

    OpenAIRE

    Marcos Costa Vieira; Marcus Vinicius Cianciaruso; Mário Almeida-Neto

    2013-01-01

    Plant-pollinator coextinctions are likely to become more frequent as habitat alteration and climate change continue to threaten pollinators. The consequences of the resulting collapse of plant communities will depend partly on how quickly plant functional and phylogenetic diversity decline following pollinator extinctions. We investigated the functional and phylogenetic consequences of pollinator extinctions by simulating coextinctions in seven plant-pollinator networks coupled with independe...

  9. Phylogenetic diversity and co-evolutionary signals among trophic levels change across a habitat edge.

    Science.gov (United States)

    Peralta, Guadalupe; Frost, Carol M; Didham, Raphael K; Varsani, Arvind; Tylianakis, Jason M

    2015-03-01

    Incorporating the evolutionary history of species into community ecology enhances understanding of community composition, ecosystem functioning and responses to environmental changes. Phylogenetic history might partly explain the impact of fragmentation and land-use change on assemblages of interacting organisms and even determine potential cascading effects across trophic levels. However, it remains unclear whether phylogenetic diversity of basal resources is reflected at higher trophic levels in the food web. In particular, phylogenetic determinants of community structure have never been incorporated into habitat edge studies, even though edges are recognized as key factors affecting communities in fragmented landscapes. Here, we test whether phylogenetic diversity at different trophic levels (plants, herbivores and parasitoids) and signals of co-evolution (i.e. phylogenetic congruence) among interacting trophic levels change across an edge gradient between native and plantation forests. To ascertain whether there is a signal of co-evolution across trophic levels, we test whether related consumer species generally feed on related resource species. We found differences across trophic levels in how their phylogenetic diversity responded to the habitat edge gradient. Plant and native parasitoid phylogenetic diversity changed markedly across habitats, while phylogenetic variability of herbivores (which were predominantly native) did not change across habitats, though phylogenetic evenness declined in plantation interiors. Related herbivore species did not appear to feed disproportionately on related plant species (i.e. there was no signal of co-evolution) even when considering only native species, potentially due to the high trophic generality of herbivores. However, related native parasitoid species tended to feed on related herbivore species, suggesting the presence of a co-evolutionary signal at higher trophic levels. Moreover, this signal was stronger in

  10. Evolution and Phylogenetic Diversity of Yam Species (Dioscorea spp.: Implication for Conservation and Agricultural Practices.

    Directory of Open Access Journals (Sweden)

    Marie Florence Sandrine Ngo Ngwe

    Full Text Available Yams (Dioscorea spp. consist of approximately 600 species. Presently, these species are threatened by genetic erosion due to many factors such as pest attacks and farming practices. In parallel, complex taxonomic boundaries in this genus makes it more challenging to properly address the genetic diversity of yam and manage its germplasm. As a first step toward evaluating and preserving the genetic diversity yam species, we use a phylogenetic diversity (PD approach that has the advantage to investigate phylogenetic relationships and test hypotheses of species monophyly while alleviating to the problem of ploidy variation within and among species. The Bayesian phylogenetic analysis of 62 accessions from 7 species from three regions of Cameroon showed that most Dioscorea sections were monophyletic, but species within sections were generally non-monophyletic. The wild species D. praehensilis and cultivated D. cayenensis were the species with the highest PD. At the opposite, D. esculenta has a low PD and future studies should focus on this species to properly address its conservation status. We also show that wild species show a stronger genetic structure than cultivated species, which potentially reflects the management of the yam germplasm by farmers. These findings show that phylogenetic diversity is a promising approach for an initial investigation of genetic diversity in a crop consisting of closely related species.

  11. Mapping genetic and phylogenetic diversity of a temperate forest using remote sensing based upscaling methods

    Science.gov (United States)

    Escriba, C. G.; Yamasaki, E.; Leiterer, R.; Tedder, A.; Shimizu, K.; Morsdorf, F.; Schaepman, M. E.

    2015-12-01

    Functioning and resilience of forest ecosystems under environmental pressures increases when biodiversity at genetic, species, canopy and ecosystem level is higher. Therefore mapping and monitoring diversity becomes a necessity to assess changes in ecosystems and understanding their consequences. Diversity can be assessed by using different metrics, such as diversity of functional traits or genetic diversity amongst others. In-situ approaches have provided useful, but usually spatially constrained information, often dependent on expert knowledge. We propose using remote sensing in combination with in-situ sampling at different spatial scales. We map phylogenetic and genetic diversity using airborne imaging spectroscopy in combination with terrestrial and airborne laser scanning, as well as exhaustive in-situ sampling schemes. To this end, we propose to link leaf optical properties using a taxonomic approach (spectranomics) to genetic and phylogenetic diversity. The test site is a managed mixed temperate forest on the south-facing slope of Laegern Mountain, Switzerland (47°28'42.0" N, 8°21'51.8" E, 682 m.a.s.l.). The intensive sampling area is roughly 300m x 300m and dominant species are European beech (Fagus sylvatica) and Ash (Fraxinus excelsior). We perform phylogenetic and intraspecific genetic variation analyses for the five most dominant tree species at the test site. For these species, information on functional biochemical and architectural plant traits diversity is retrieved from imaging spectroscopy and laser scanning data and validated with laboratory and in-situ measurements. To assess regional-scale genetic diversity, the phylogenetic and genetic signals are quantified using the remote sensing data, resulting in spatially distributed intra-specific genetic variation. We discuss the usefulness of combined remote sensing and in-situ sampling, to bridge diversity scales from genetic to canopy level.

  12. The phylogenetic position and diversity of the enigmatic mongrel frog Nothophryne Poynton, 1963 (Amphibia, Anura).

    Science.gov (United States)

    Bittencourt-Silva, Gabriela B; Conradie, Werner; Siu-Ting, Karen; Tolley, Krystal A; Channing, Alan; Cunningham, Michael; Farooq, Harith M; Menegon, Michele; Loader, Simon P

    2016-06-01

    The phylogenetic relationships of the African mongrel frog genus Nothophryne are poorly understood. We provide the first molecular assessment of the phylogenetic position of, and diversity within, this monotypic genus from across its range-the Afromontane regions of Malawi and Mozambique. Our analysis using a two-tiered phylogenetic approach allowed us to place the genus in Pyxicephalidae. Within the family, Nothophryne grouped with Tomopterna, a hypothesis judged significantly better than alternative hypotheses proposed based on morphology. Our analyses of populations across the range of Nothophryne suggest the presence of several cryptic species, at least one species per mountain. Formal recognition of these species is pending but there is a major conservation concern for these narrowly distributed populations in an area impacted by major habitat change. The phylogenetic tree of pyxicephalids is used to examine evolution of life history, ancestral habitat, and biogeography of this group. PMID:27001603

  13. Alpine cushion plants inhibit the loss of phylogenetic diversity in severe environments.

    Science.gov (United States)

    Butterfield, B J; Cavieres, L A; Callaway, R M; Cook, B J; Kikvidze, Z; Lortie, C J; Michalet, R; Pugnaire, F I; Schöb, C; Xiao, S; Zaitchek, B; Anthelme, F; Björk, R G; Dickinson, K; Gavilán, R; Kanka, R; Maalouf, J-P; Noroozi, J; Parajuli, R; Phoenix, G K; Reid, A; Ridenour, W; Rixen, C; Wipf, S; Zhao, L; Brooker, R W

    2013-04-01

    Biotic interactions can shape phylogenetic community structure (PCS). However, we do not know how the asymmetric effects of foundation species on communities extend to effects on PCS. We assessed PCS of alpine plant communities around the world, both within cushion plant foundation species and adjacent open ground, and compared the effects of foundation species and climate on alpha (within-microsite), beta (between open and cushion) and gamma (open and cushion combined) PCS. In the open, alpha PCS shifted from highly related to distantly related with increasing potential productivity. However, we found no relationship between gamma PCS and climate, due to divergence in phylogenetic composition between cushion and open sub-communities in severe environments, as demonstrated by increasing phylo-beta diversity. Thus, foundation species functioned as micro-refugia by facilitating less stress-tolerant lineages in severe environments, erasing a global productivity - phylogenetic diversity relationship that would go undetected without accounting for this important biotic interaction. PMID:23346919

  14. Relating phylogenetic and functional diversity among denitrifiers and quantifying their capacity to predict community functioning

    Directory of Open Access Journals (Sweden)

    JoanaFalcão Salles

    2012-06-01

    Full Text Available Genetic diversity of phylogenetic or functional markers is widely used as a proxy of microbial diversity. However, it remains unclear at what extent functional diversity, gene sequence diversity and community functioning are linked. We analysed, for a range of denitrifying bacteria, the relationships between (i the similarity of functional traits evaluated from metabolic profiles (BIOLOG plates or from N2O accumulation patterns on different C sources, and (ii the similarity of phylogenetic (16S rRNA gene or functional (nir gene markers. We also calculated different proxies for the diversity of denitrifier community based on taxa richness, phylogenetic or functional similarities, and evaluated their performance in inferring the functioning of assembled denitrifying communities. For individual strains, the variation in the 16S rRNA gene sequence explained only 10% of the variation in metabolic patterns and were not related to N2O accumulation. The latter was correlated with the similarity of nitrite reductase residues. When nir genes were analysed separately, the similarity in amino acids coded by the nirS genes accounted for 48% of the variance of the observed pattern of N2O accumulation, whereas nirK amino acid residues were unrelated to N2O accumulation. For bacterial assemblages, phylogenetic diversity and mean community dissimilarity, calculated using 16S rRNA gene sequences, and functional diversity measures associated with BIOLOG, predicted poorly the variation in the functioning of assembled communities (below 15%. In contrast, the proxies of functional diversity based on N2O accumulation patterns performed better and explained from 23 to 42% of the variation in community functioning. Amongst those, community niche was the best metric, indicating the importance of complementarity for carbon resources among taxa in the context of denitrification.

  15. Phylogenetic beta diversity of native and alien species in European urban floras

    Czech Academy of Sciences Publication Activity Database

    Ricotta, C.; La Sorte, F. A.; Pyšek, Petr; Rapson, G. L.; Celesti-Grapow, L.; Thompson, K.

    2012-01-01

    Roč. 21, č. 7 (2012), s. 751-759. ISSN 1466-822X R&D Projects: GA MŠk LC06073 Institutional research plan: CEZ:AV0Z60050516 Institutional support: RVO:67985939 Keywords : phylogenetic beta diversity * urban floras * plant invasions Subject RIV: EF - Botanics Impact factor: 7.223, year: 2012

  16. The Primary Results of Analyses on The Archaeal and Bacterial Diversity of Active Cave Environments Settled in Limestones at Southern Turkey

    Science.gov (United States)

    Tok, Ezgi; Kurt, Halil; Tunga Akarsubasi, A.

    2016-04-01

    The microbial diversity of cave sediments which are obtained from three different caves named Insuyu, Balatini and Altınbeşik located at Southern Turkey has been investigated using molecular methods for biomineralization . The total number of 22 samples were taken in duplicates from the critical zones of the caves at where the water activity is observed all year round. Microbial communities were monitored by 16S rRNA gene based PCR-DGGE (Polymerase Chain Reaction - Denaturating Gradient Gel Electrophoresis) methodology. DNA were extracted from the samples by The PowerSoil® DNA Isolation Kit (MO BIO Laboratories inc., CA) with the modifications on the producer's protocol. The synthetic DNA molecule poly-dIdC was used to increase the yield of PCR amplification via blocking the reaction between CaCO3 and DNA molecules. Thereafter samples were amplified by using both Archaeal and Bacterial universal primers (ref). Subsequently, archaeal and bacterial diversities in cave sediments, were investigated to be able to compare with respect to their similarities by using DGGE. DGGE patterns were analysed with BioNumerics software 5.1. Similarity matrix and dendograms of the DGGE profiles were generated based on the Dice correlation coefficient (band-based) and unweighted pair-group method with arithmetic mean (UPGMA). The structural diversity of the microbial community was examined by the Shannon index of general diversity (H). Similtaneously, geochemical analyses of the sediment samples were performed within the scope of this study. Total organic carbon (TOC), x-ray diffraction spectroscopy (XRD) and x-ray fluorescence spectroscopy (XRF) analysis of sediments were also implemented. The extensive results will be obtained at the next stages of the study currently carried on.

  17. Ecological Diversity in South American Mammals: Their Geographical Distribution Shows Variable Associations with Phylogenetic Diversity and Does Not Follow the Latitudinal Richness Gradient

    OpenAIRE

    Paula Nilda Fergnani; Adriana Ruggiero

    2015-01-01

    The extent to which the latitudinal gradient in species richness may be paralleled by a similar gradient of increasing functional or phylogenetic diversity is a matter of controversy. We evaluated whether taxonomic richness (TR) is informative in terms of ecological diversity (ED, an approximation to functional diversity) and phylogenetic diversity (AvPD) using data on 531 mammal species representing South American old autochthonous (marsupials, xenarthrans), mid-Cenozoic immigrants (hystrico...

  18. Phylogenetic diversity and biogeography of the Mamiellophyceae lineage of eukaryotic phytoplankton across the oceans.

    Science.gov (United States)

    Monier, Adam; Worden, Alexandra Z; Richards, Thomas A

    2016-08-01

    High-throughput diversity amplicon sequencing of marine microbial samples has revealed that members of the Mamiellophyceae lineage are successful phytoplankton in many oceanic habitats. Indeed, these eukaryotic green algae can dominate the picoplanktonic biomass, however, given the broad expanses of the oceans, their geographical distributions and the phylogenetic diversity of some groups remain poorly characterized. As these algae play a foundational role in marine food webs, it is crucial to assess their global distribution in order to better predict potential changes in abundance and community structure. To this end, we analyzed the V9-18S small subunit rDNA sequences deposited from the Tara Oceans expedition to evaluate the diversity and biogeography of these phytoplankton. Our results show that the phylogenetic composition of Mamiellophyceae communities is in part determined by geographical provenance, and do not appear to be influenced - in the samples recovered - by water depth, at least at the resolution possible with the V9-18S. Phylogenetic classification of Mamiellophyceae sequences revealed that the Dolichomastigales order encompasses more sequence diversity than other orders in this lineage. These results indicate that a large fraction of the Mamiellophyceae diversity has been hitherto overlooked, likely because of a combination of size fraction, sequencing and geographical limitations. PMID:26929141

  19. Phylogenetic diversity of stress signalling pathways in fungi

    Directory of Open Access Journals (Sweden)

    Stansfield Ian

    2009-02-01

    Full Text Available Abstract Background Microbes must sense environmental stresses, transduce these signals and mount protective responses to survive in hostile environments. In this study we have tested the hypothesis that fungal stress signalling pathways have evolved rapidly in a niche-specific fashion that is independent of phylogeny. To test this hypothesis we have compared the conservation of stress signalling molecules in diverse fungal species with their stress resistance. These fungi, which include ascomycetes, basidiomycetes and microsporidia, occupy highly divergent niches from saline environments to plant or mammalian hosts. Results The fungi displayed significant variation in their resistance to osmotic (NaCl and sorbitol, oxidative (H2O2 and menadione and cell wall stresses (Calcofluor White and Congo Red. There was no strict correlation between fungal phylogeny and stress resistance. Rather, the human pathogens tended to be more resistant to all three types of stress, an exception being the sensitivity of Candida albicans to the cell wall stress, Calcofluor White. In contrast, the plant pathogens were relatively sensitive to oxidative stress. The degree of conservation of osmotic, oxidative and cell wall stress signalling pathways amongst the eighteen fungal species was examined. Putative orthologues of functionally defined signalling components in Saccharomyces cerevisiae were identified by performing reciprocal BLASTP searches, and the percent amino acid identities of these orthologues recorded. This revealed that in general, central components of the osmotic, oxidative and cell wall stress signalling pathways are relatively well conserved, whereas the sensors lying upstream and transcriptional regulators lying downstream of these modules have diverged significantly. There was no obvious correlation between the degree of conservation of stress signalling pathways and the resistance of a particular fungus to the corresponding stress. Conclusion Our

  20. Trends over time in tree and seedling phylogenetic diversity indicate regional differences in forest biodiversity change.

    Science.gov (United States)

    Potter, Kevin M; Woodall, Christopher W

    2012-03-01

    Changing climate conditions may impact the short-term ability of forest tree species to regenerate in many locations. In the longer term, tree species may be unable to persist in some locations while they become established in new places. Over both time frames, forest tree biodiversity may change in unexpected ways. Using repeated inventory measurements five years apart from more than 7000 forested plots in the eastern United States, we tested three hypotheses: phylogenetic diversity is substantially different from species richness as a measure of biodiversity; forest communities have undergone recent changes in phylogenetic diversity that differ by size class, region, and seed dispersal strategy; and these patterns are consistent with expected early effects of climate change. Specifically, the magnitude of diversity change across broad regions should be greater among seedlings than in trees, should be associated with latitude and elevation, and should be greater among species with high dispersal capacity. Our analyses demonstrated that phylogenetic diversity and species richness are decoupled at small and medium scales and are imperfectly associated at large scales. This suggests that it is appropriate to apply indicators of biodiversity change based on phylogenetic diversity, which account for evolutionary relationships among species and may better represent community functional diversity. Our results also detected broadscale patterns of forest biodiversity change that are consistent with expected early effects of climate change. First, the statistically significant increase over time in seedling diversity in the South suggests that conditions there have become more favorable for the reproduction and dispersal of a wider variety of species, whereas the significant decrease in northern seedling diversity indicates that northern conditions have become less favorable. Second, we found weak correlations between seedling diversity change and latitude in both zones

  1. Phylogenetic Diversity of Nitrogen Fixation Genes in the Symbiotic Microbial Community in the Gut of Diverse Termites

    OpenAIRE

    Ohkuma, Moriya; Noda, Satoko; Kudo, Toshiaki

    1999-01-01

    Nitrogen fixation by the microorganisms in the gut of termites is one of the crucial aspects of symbiosis, since termites usually thrive on a nitrogen-poor diet. The phylogenetic diversity of the nitrogen-fixing organisms within the symbiotic community in the guts of various termite species was investigated without culturing the resident microorganisms. A portion of the dinitrogenase reductase gene (nifH) was directly amplified from DNA extracted from the mixed population in the termite gut. ...

  2. Defining conservation priorities for freshwater fishes according to taxonomic, functional, and phylogenetic diversity

    Science.gov (United States)

    Strecker, A.L.; Olden, J.D.; Whittier, Joanna B.; Paukert, C.P.

    2011-01-01

    To date, the predominant use of systematic conservation planning has been to evaluate and conserve areas of high terrestrial biodiversity. Although studies in freshwater ecosystems have received recent attention, research has rarely considered the potential tradeoffs between protecting different dimensions of biodiversity and the ecological processes that maintain diversity. We provide the first systematic prioritization for freshwaters (focusing on the highly threatened and globally distinct fish fauna of the Lower Colorado River Basin, USA) simultaneously considering scenarios of: taxonomic, functional, and phylogenetic diversity;contemporary threats to biodiversity (including interactions with nonnative species);and future climate change and human population growth. There was 75% congruence between areas of highest conservation priority for different aspects of biodiversity, suggesting that conservation efforts can concurrently achieve strong complementarity among all types of diversity. However, sizable fractions of the landscape were incongruent across conservation priorities for different diversity scenarios, underscoring the importance of considering multiple dimensions of biodiversity and highlighting catchments that contribute disproportionately to taxonomic, functional, and phylogenetic diversity in the region. Regions of projected human population growth were not concordant with conservation priorities;however, higher human population abundance will likely have indirect effects on native biodiversity by increasing demand for water. This will come in direct conflict with projected reductions in precipitation and warmer temperatures, which have substantial overlap with regions of high contemporary diversity. Native and endemic fishes in arid ecosystems are critically endangered by both current and future threats, but our results highlight the use of systematic conservation planning for the optimal allocation of limited resources that incorporates multiple

  3. Phylogenetic congruence of lichenised fungi and algae is affected by spatial scale and taxonomic diversity

    Directory of Open Access Journals (Sweden)

    Hannah L. Buckley

    2014-09-01

    Full Text Available The role of species’ interactions in structuring biological communities remains unclear. Mutualistic symbioses, involving close positive interactions between two distinct organismal lineages, provide an excellent means to explore the roles of both evolutionary and ecological processes in determining how positive interactions affect community structure. In this study, we investigate patterns of co-diversification between fungi and algae for a range of New Zealand lichens at the community, genus, and species levels and explore explanations for possible patterns related to spatial scale and pattern, taxonomic diversity of the lichens considered, and the level sampling replication. We assembled six independent datasets to compare patterns in phylogenetic congruence with varied spatial extent of sampling, taxonomic diversity and level of specimen replication. For each dataset, we used the DNA sequences from the ITS regions of both the fungal and algal genomes from lichen specimens to produce genetic distance matrices. Phylogenetic congruence between fungi and algae was quantified using distance-based redundancy analysis and we used geographic distance matrices in Moran’s eigenvector mapping and variance partitioning to evaluate the effects of spatial variation on the quantification of phylogenetic congruence. Phylogenetic congruence was highly significant for all datasets and a large proportion of variance in both algal and fungal genetic distances was explained by partner genetic variation. Spatial variables, primarily at large and intermediate scales, were also important for explaining genetic diversity patterns in all datasets. Interestingly, spatial structuring was stronger for fungal than algal genetic variation. As the spatial extent of the samples increased, so too did the proportion of explained variation that was shared between the spatial variables and the partners’ genetic variation. Different lichen taxa showed some variation in

  4. Solid and Aqueous Geochemical Controls on Phylogenetic Diversity and Abundance of Microbial Biofilms

    Science.gov (United States)

    Jones, A. A.; Bennett, P. C.

    2015-12-01

    In the subsurface, the vast majority of microorganisms are found in biofilms attached to mineral surfaces. The fickle nature of these environments (chemically and physically) likely causes dynamic ecological shifts in these microbial communities. We used laboratory biofilm reactors (inoculated with a diverse subsurface community) to explore the role of mineralogy as part of a microbe-mineral-water ecosystem under variable pressures (mineralogy, pH, carbon, phosphate). Following multivariate analyses, pH was identified as the key physicochemical property associated with variation in both phylogenetic and taxonomic diversity as well as overall community structure (Pbiofilm accumulation (Pbiofilm accumulation (Pbiofilm accumulation (Pbiofilms. All reactors harbored structurally, taxonomically, and phylogenetically distinct microbial communities.

  5. Evaluating Methods for Isolating Total RNA and Predicting the Success of Sequencing Phylogenetically Diverse Plant Transcriptomes

    OpenAIRE

    M Johnson; Carpenter, E; Tian, Z.; Bruskiewich, R.; Burris, J.; Carrigan, C.; Chase, M; Clarke, N.; Covshoff, S.; Depamphilis, C.; Edger, P.; Goh, F.; Graham, S; S Greiner; Hibberd, J.

    2012-01-01

    Next-generation sequencing plays a central role in the characterization and quantification of transcriptomes. Although numerous metrics are purported to quantify the quality of RNA, there have been no large-scale empirical evaluations of the major determinants of sequencing success. We used a combination of existing and newly developed methods to isolate total RNA from 1115 samples from 695 plant species in 324 families, which represents >900 million years of phylogenetic diversity from green...

  6. Diversity Dynamics in Nymphalidae Butterflies: Effect of Phylogenetic Uncertainty on Diversification Rate Shift Estimates

    OpenAIRE

    Peña, Carlos; Espeland, Marianne

    2015-01-01

    The family Nymphalidae is the largest family within the true butterflies and has been used to develop hypotheses explaining evolutionary interactions between plants and insects. Theories of insect and hostplant dynamics predict accelerated diversification in some scenarios. We investigated whether phylogenetic uncertainty affects a commonly used method (MEDUSA, modelling evolutionary diversity using stepwise AIC) for estimating shifts in diversification rates in lineages of the family Nymphal...

  7. Divergence Times and Phylogenetic Patterns of Sebacinales, a Highly Diverse and Widespread Fungal Lineage

    OpenAIRE

    Garnica, Sigisfredo; Riess, Kai; Max E Schön; Oberwinkler, Franz; Sabrina D Setaro

    2016-01-01

    Patterns of geographic distribution and composition of fungal communities are still poorly understood. Widespread occurrence in terrestrial ecosystems and the unique richness of interactions of Sebacinales with plants make them a target group to study evolutionary events in the light of nutritional lifestyle. We inferred diversity patterns, phylogenetic structures and divergence times of Sebacinales with respect to their nutritional lifestyles by integrating data from fossil-calibrated phylog...

  8. Ecosystem Functions across Trophic Levels Are Linked to Functional and Phylogenetic Diversity

    OpenAIRE

    Thompson, Patrick L.; Jonathan Davies, T; Andrew Gonzalez

    2015-01-01

    In experimental systems, it has been shown that biodiversity indices based on traits or phylogeny can outperform species richness as predictors of plant ecosystem function. However, it is unclear whether this pattern extends to the function of food webs in natural ecosystems. Here we tested whether zooplankton functional and phylogenetic diversity explains the functioning of 23 natural pond communities. We used two measures of ecosystem function: (1) zooplankton community biomass and (2) phyt...

  9. Actinomycetes from Red Sea Sponges: Sources for Chemical and Phylogenetic Diversity

    OpenAIRE

    Usama Ramadan Abdelmohsen; Chen Yang; Hannes Horn; Dina Hajjar; Timothy Ravasi; Ute Hentschel

    2014-01-01

    The diversity of actinomycetes associated with marine sponges collected off Fsar Reef (Saudi Arabia) was investigated in the present study. Forty-seven actinomycetes were cultivated and phylogenetically identified based on 16S rRNA gene sequencing and were assigned to 10 different actinomycete genera. Eight putatively novel species belonging to genera Kocuria, Mycobacterium, Nocardia, and Rhodococcus were identified based on sequence similarity values below 98.2% to other 16S rRNA gene sequen...

  10. Molecular Phylogenetic Diversity and Spatial Distribution of Bacterial Communities in Cooling Stage during Swine Manure Composting

    OpenAIRE

    Guo, Yan; Zhang, Jinliang; Yan, Yongfeng; Wu, Jian; Zhu, Nengwu; Deng, Changyan

    2015-01-01

    Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and subsequent sub-cloning and sequencing were used in this study to analyze the molecular phylogenetic diversity and spatial distribution of bacterial communities in different spatial locations during the cooling stage of composted swine manure. Total microbial DNA was extracted, and bacterial near full-length 16S rRNA genes were subsequently amplified, cloned, RFLP-screened, and sequenced. A total of 420 positive ...

  11. Relative roles of local disturbance, current climate and palaeoclimate in determining phylogenetic and functional diversity in Chinese forests

    Directory of Open Access Journals (Sweden)

    G. Feng

    2013-09-01

    Full Text Available The main processes underlying the generation and maintenance of biodiversity include both local factors such as competition and abiotic filtering and regional forces such as palaeoclimate, speciation and dispersal. While the effects of regional and local drivers on species diversity are increasingly studied, their relative importance for other aspects of diversity, notably phylogenetic and functional diversity is so far little studied. Here, we link data from large Chinese forest plots to data on current and Last Glacial Maximum (LGM climate as well as local disturbance regimes to study their relative roles in determining woody plant phylogenetic and functional diversity in this important hotspot for woody plant diversity. Local disturbance was the best predictor of functional diversity as represented by maximum canopy height (Hmax, probably reflecting the dominant role of competition for light in determining the forest Hmax structure. In contrast, the LGM-present anomaly in temperature was the factor with the strongest explanatory power for phylogenetic diversity, with modern climate also important. Hence, local contemporary and regional historical factors have highly contrasting importance for the geographic patterns of the functional and phylogenetic aspects of Chinese forest woody plant diversity. Importantly, contemporary factors are of overriding importance for functional diversity, while palaeoclimate has left a strong signature in the phylogenetic diversity patterns.

  12. Revisiting phylogenetic diversity and cryptic species of Cenococcum geophilum sensu lato.

    Science.gov (United States)

    Obase, Keisuke; Douhan, Greg W; Matsuda, Yosuke; Smith, Matthew E

    2016-08-01

    The fungus Cenococcum geophilum Fr. (Dothideomycetes, Ascomycota) is one of the most common ectomycorrhizal fungi in boreal to temperate regions. A series of molecular studies has demonstrated that C. geophilum is monophyletic but a heterogeneous species or a species complex. Here, we revisit the phylogenetic diversity of C. geophilum sensu lato from a regional to intercontinental scale by using new data from Florida (USA) along with existing data in GenBank from Japan, Europe, and North America. The combination of internal transcribed spacer (ITS) ribosomal DNA and the glyceraldehyde-3-phosphate dehydrogenase (GAPDH) gene resolved six well-supported lineages (87-100 % bootstrap values) that are closely related to each other and a seventh lineage that is phylogenetically distinct. A multi-locus analysis (small subunit (SSU), large subunit (LSU), translational elongation factor (TEF), and the largest and second-largest subunits of RNA polymerase II (RPB1 and RPB2)) revealed that the divergent lineage is the sister group to all other known Cenococcum isolates. Isolates of the divergent lineage grow fast on nutrient media and do not form ectomycorrhizas on seedlings of several pine and oak species. Our results indicate that C. geophilum sensu lato includes more phylogenetically distinct cryptic species than have previously been reported. Furthermore, the divergent lineage appears to be a non-mycorrhizal sister group. We discuss the phylogenetic diversity of C. geophilum sensu lato and argue in favor of species recognition based on phylogenetic and ecological information in addition to morphological characteristics. A new genus and species (Pseudocenococcum floridanum gen. et sp. nov.) is proposed to accommodate a divergent and putatively non-mycorrhizal lineage. PMID:26968743

  13. A database of phylogenetically atypical genes in archaeal and bacterial genomes, identified using the DarkHorse algorithm

    OpenAIRE

    Allen Eric E; Gaasterland Terry; Podell Sheila

    2008-01-01

    Abstract Background The process of horizontal gene transfer (HGT) is believed to be widespread in Bacteria and Archaea, but little comparative data is available addressing its occurrence in complete microbial genomes. Collection of high-quality, automated HGT prediction data based on phylogenetic evidence has previously been impractical for large numbers of genomes at once, due to prohibitive computational demands. DarkHorse, a recently described statistical method for discovering phylogeneti...

  14. Archaeal Diversity in Biofilm Technologies Applied to Treat Urban and Industrial Wastewater: Recent Advances and Future Prospects

    Directory of Open Access Journals (Sweden)

    Jesús González-López

    2013-09-01

    Full Text Available Biological wastewater treatment (WWT frequently relies on biofilms for the removal of anthropogenic contaminants. The use of inert carrier materials to support biofilm development is often required, although under certain operating conditions microorganisms yield structures called granules, dense aggregates of self-immobilized cells with the characteristics of biofilms maintained in suspension. Molecular techniques have been successfully applied in recent years to identify the prokaryotic communities inhabiting biofilms in WWT plants. Although methanogenic Archaea are widely acknowledged as key players for the degradation of organic matter in anaerobic bioreactors, other biotechnological functions fulfilled by Archaea are less explored, and research on their significance and potential for WWT is largely needed. In addition, the occurrence of biofilms in WWT plants can sometimes be a source of operational problems. This is the case for membrane bioreactors (MBR, an advanced technology that combines conventional biological treatment with membrane filtration, which is strongly limited by biofouling, defined as the undesirable accumulation of microbial biofilms and other materials on membrane surfaces. The prevalence and spatial distribution of archaeal communities in biofilm-based WWT as well as their role in biofouling are reviewed here, in order to illustrate the significance of this prokaryotic cellular lineage in engineered environments devoted to WWT.

  15. Novel viral genomes identified from six metagenomes reveal wide distribution of archaeal viruses and high viral diversity in terrestrial hot springs.

    Science.gov (United States)

    Gudbergsdóttir, Sóley Ruth; Menzel, Peter; Krogh, Anders; Young, Mark; Peng, Xu

    2016-03-01

    Limited by culture-dependent methods the number of viruses identified from thermophilic Archaea and Bacteria is still very small. In this study we retrieved viral sequences from six hot spring metagenomes isolated worldwide, revealing a wide distribution of four archaeal viral families, Ampullaviridae, Bicaudaviridae, Lipothrixviridae and Rudiviridae. Importantly, we identified 10 complete or near complete viral genomes allowing, for the first time, an assessment of genome conservation and evolution of the Ampullaviridae family as well as Sulfolobus Monocaudavirus 1 (SMV1)-related viruses. Among the novel genomes, one belongs to a putative thermophilic virus infecting the bacterium Hydrogenobaculum, for which no virus has been reported in the literature. Moreover, a high viral diversity was observed in the metagenomes, especially among the Lipothrixviridae, as indicated by the large number of unique contigs and the lack of a completely assembled genome for this family. This is further supported by the large number of novel genes in the complete and partial genomes showing no sequence similarities to public databases. CRISPR analysis revealed hundreds of novel CRISPR loci and thousands of novel CRISPR spacers from each metagenome, reinforcing the notion of high viral diversity in the thermal environment. PMID:26439881

  16. Variation in sulfide tolerance of photosystem II in phylogenetically diverse cyanobacteria from sulfidic habitats

    Science.gov (United States)

    Miller, Scott R.; Bebout, Brad M.

    2004-01-01

    Physiological and molecular phylogenetic approaches were used to investigate variation among 12 cyanobacterial strains in their tolerance of sulfide, an inhibitor of oxygenic photosynthesis. Cyanobacteria from sulfidic habitats were found to be phylogenetically diverse and exhibited an approximately 50-fold variation in photosystem II performance in the presence of sulfide. Whereas the degree of tolerance was positively correlated with sulfide levels in the environment, a strain's phenotype could not be predicted from the tolerance of its closest relatives. These observations suggest that sulfide tolerance is a dynamic trait primarily shaped by environmental variation. Despite differences in absolute tolerance, similarities among strains in the effects of sulfide on chlorophyll fluorescence induction indicated a common mode of toxicity. Based on similarities with treatments known to disrupt the oxygen-evolving complex, it was concluded that sulfide toxicity resulted from inhibition of the donor side of photosystem II.

  17. Factors shaping bacterial phylogenetic and functional diversity in coastal waters of the NW Mediterranean Sea

    Science.gov (United States)

    Boras, Julia A.; Vaqué, Dolors; Maynou, Francesc; Sà, Elisabet L.; Weinbauer, Markus G.; Sala, Maria Montserrat

    2015-03-01

    To evaluate the main factors shaping bacterioplankton phylogenetic and functional diversity in marine coastal waters, we carried out a two-year study based on a monthly sampling in Blanes Bay (NW Mediterranean). We expected the key factors driving bacterial diversity to be (1) temperature and nutrient concentration, together with chlorophyll a concentration as an indicator of phytoplankton biomass and, hence, a carbon source for bacteria (here called bottom-up factors), and (2) top-down pressure (virus- and protist-mediated mortality of bacteria). Phylogenetic diversity was analyzed by denaturing gradient gel electrophoresis (DGGE) of 16S rRNA. Functional diversity was assessed by using monomeric carbon sources in Biolog EcoPlates and by determining the activity of six extracellular enzymes. Our results indicate that the bacterial phylogenetic and functional diversity in this coastal system is shaped mainly by bottom-up factors. A dendrogram analysis of the DGGE banding patterns revealed three main sample clusters. Two clusters differed significantly in temperature, nitrate and chlorophyll a concentration, and the third was characterized by the highest losses of bacterial production due to viral lysis detected over the whole study period. Protistan grazing had no effect on bacterial functional diversity, since there were no correlations between protist-mediated mortality (PMM) and extracellular enzyme activities, and utilization of only two out of the 31 carbon sources (N-acetyl-D-glucosamine and α-cyclodextrin) was correlated with PMM. In contrast, virus-mediated mortality correlated with changes in the percentage of use of four carbon sources, and also with specific leu-aminopeptidase and β-glucosidase activity. This suggests that viral lysate provides a pool of labile carbon sources, presumably including amino acids and glucose, which may inhibit proteolytic and glucosidic activity. Our results indicate that bottom-up factors play a more important role than

  18. Reappraisal of phylogenetic status and genetic diversity analysis of Asian population of Lentinula edodes

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Phylogenetic relationship within the Lentinula genus is constructed based on the sequenced ITS fragments of the 60Chinese wild L. edodes isolates and the sequence data of 48 isolates of different species from other districts downloaded from the GenBank. The 108 isolates of Lentinula genus are divided into two branches and seven groups, one branch and two groups in the New World, and the other branch and five groups in the Old World, and the isolates clustering of different groups corresponds obviously with the classification of the morphological species. Asian isolates are partitioned in group Ⅰ and Ⅴ, two of the five groups of the Old World,by which the germplasm resources status represented is of great importance shown by the phylogenetic analysis. Group V which fills up the blank of geographic distribution has become one of the mainstream groups with an increased isolate number, while group Ⅰ has a tendency to dissimilate into two subgroups (Ia and Ib) with a huge isolate quantity and a coverage of most tested districts, suggesting that China (or Asia) is an important genetic diversity center of the natural population of Lentinula genus. Genetic analysis of Asian isolates based on groups Ia, Ib and group V indicates that the diversity of the east coastal-land, northwestern highland and southwestern China and Himalayas districts is the most plentiful, which is the three priorities in diversity protection of Asian Lentinula population.

  19. Phylogenetic and functional diversity of nitrogen cycling microbes in coastal sediments

    Directory of Open Access Journals (Sweden)

    Xiaoli Zhang

    2013-07-01

    Full Text Available The coastal zone contains diverse habitats which are usually characterized by strong environmental gradients (e.g. salinity, nutrients and pollutants. This makes the coastal zone an ideal experimental laboratory for describing microbial diversity and testing hypotheses on community structure, function and control. Coastal sediment is of significance in nutrient regeneration and transformation involving different assemblages of microbes in the nitrogen cycle. This review focuses on 16S rRNA gene-based phylogenetic diversity and the key enzyme encoding gene-based (e.g. nifH, amoA, narG, nirS, nirK, nosZ, nrfA, hzo and hzs functional diversity of nitrogen fixing, ammonia oxidizing and anaerobic ammonia oxidation (Anammox bacteria as well as bacteria and fungi involved in denitrification and dissimilatory nitrate reduction to ammonium (DNRA. Characteristics of community composition and diversity of nitrogen cycling microbes in different habitats (e.g. estuarine, intertidal flats, seagrass or seaweed beds, mangroves, salt marsh, coral reefs, and shallow seas, and their spatiotemporal patterns under benthic pollution or bioturbation are reviewed. Future directions for a better understanding diversity of nitrogen cycling microbes are suggested, such as culture methods and technologies, and single-cell sequencing, etc.

  20. Structure and phylogenetic diversity of post-fire ectomycorrhizal communities of maritime pine.

    Science.gov (United States)

    Rincón, A; Santamaría, B P; Ocaña, L; Verdú, M

    2014-02-01

    Environmental disturbances define the diversity and assemblage of species, affecting the functioning of ecosystems. Fire is a major disturbance of Mediterranean pine forests. Pines are highly dependent on the ectomycorrhizal (EM) fungal symbiosis, which is critical for tree recruitment under primary succession. To determine the effects of time since fire on the structure and recovery of EM fungal communities, we surveyed the young Pinus pinaster regenerate in three sites differing in the elapsed time after the last fire event. Pine roots were collected, and EM fungi characterized by sequencing the internal transcribed spacer (ITS) and the large subunit (LSU) regions of the nuclear ribosomal (nr)-DNA. The effects of the elapsed time after fire on the EM community structure (richness, presence/absence of fungi, phylogenetic diversity) and on soil properties were analysed.Fungal richness decreased with the elapsed time since the fire; although, the phylogenetic diversity of the EM community increased. Soil properties were different depending on the elapsed time after fire and particularly, the organic matter, carbon-to-nitrogen (C/N) ratio, nitrogen and iron significantly correlated with the assemblage of fungal species. Ascomycetes, particularly Tuberaceae and Pezizales, were significantly over-represented on saplings in the burned site. On seedlings, a significant over-representation of Rhizopogonaceae and Atheliaceae was observed in the most recently burned site, while other fungi (i.e. Cortinariaceae) were significantly under-represented. Our results are consistent with the hypothesis that fire can act as a selective agent by printing a phylogenetic signal on the EM fungal communities associated with naturally regenerated pines, pointing out to some groups as potential fire-adapted fungi. PMID:23955264

  1. Phylogenetic diversity and ecophysiology of Candidate phylum Saccharibacteria in activated sludge

    DEFF Research Database (Denmark)

    Kindaichi, Tomonori; Yamaoka, Shiro; Uehara, Ryohei;

    2016-01-01

    Candidate phylum Saccharibacteria (former TM7) are abundant and widespread in nature, but little is known about their ecophysiology and detailed phylogeny. In this study phylogeny, morphology and ecophysiology of Saccharibacteria were investigated in activated sludge from nine wastewater treatment......-labeled fluorescence and FISH (ELF-FISH). No uptake of acetate, propionate, pyruvate, glycerol and ethanol was observed. These results indicate that Saccharibacteria is a phylogenetically diverse group and play a role in the degradation of various organic compounds as well as sugar compounds under aerobic-, nitrate...

  2. Diversity dynamics in Nymphalidae butterflies: effect of phylogenetic uncertainty on diversification rate shift estimates.

    Directory of Open Access Journals (Sweden)

    Carlos Peña

    Full Text Available The species rich butterfly family Nymphalidae has been used to study evolutionary interactions between plants and insects. Theories of insect-hostplant dynamics predict accelerated diversification due to key innovations. In evolutionary biology, analysis of maximum credibility trees in the software MEDUSA (modelling evolutionary diversity using stepwise AIC is a popular method for estimation of shifts in diversification rates. We investigated whether phylogenetic uncertainty can produce different results by extending the method across a random sample of trees from the posterior distribution of a Bayesian run. Using the MultiMEDUSA approach, we found that phylogenetic uncertainty greatly affects diversification rate estimates. Different trees produced diversification rates ranging from high values to almost zero for the same clade, and both significant rate increase and decrease in some clades. Only four out of 18 significant shifts found on the maximum clade credibility tree were consistent across most of the sampled trees. Among these, we found accelerated diversification for Ithomiini butterflies. We used the binary speciation and extinction model (BiSSE and found that a hostplant shift to Solanaceae is correlated with increased net diversification rates in Ithomiini, congruent with the diffuse cospeciation hypothesis. Our results show that taking phylogenetic uncertainty into account when estimating net diversification rate shifts is of great importance, as very different results can be obtained when using the maximum clade credibility tree and other trees from the posterior distribution.

  3. Diversity dynamics in Nymphalidae butterflies: effect of phylogenetic uncertainty on diversification rate shift estimates.

    Science.gov (United States)

    Peña, Carlos; Espeland, Marianne

    2015-01-01

    The species rich butterfly family Nymphalidae has been used to study evolutionary interactions between plants and insects. Theories of insect-hostplant dynamics predict accelerated diversification due to key innovations. In evolutionary biology, analysis of maximum credibility trees in the software MEDUSA (modelling evolutionary diversity using stepwise AIC) is a popular method for estimation of shifts in diversification rates. We investigated whether phylogenetic uncertainty can produce different results by extending the method across a random sample of trees from the posterior distribution of a Bayesian run. Using the MultiMEDUSA approach, we found that phylogenetic uncertainty greatly affects diversification rate estimates. Different trees produced diversification rates ranging from high values to almost zero for the same clade, and both significant rate increase and decrease in some clades. Only four out of 18 significant shifts found on the maximum clade credibility tree were consistent across most of the sampled trees. Among these, we found accelerated diversification for Ithomiini butterflies. We used the binary speciation and extinction model (BiSSE) and found that a hostplant shift to Solanaceae is correlated with increased net diversification rates in Ithomiini, congruent with the diffuse cospeciation hypothesis. Our results show that taking phylogenetic uncertainty into account when estimating net diversification rate shifts is of great importance, as very different results can be obtained when using the maximum clade credibility tree and other trees from the posterior distribution. PMID:25830910

  4. Phylogenetic diversity and ecophysiology of Candidate phylum Saccharibacteria in activated sludge.

    Science.gov (United States)

    Kindaichi, Tomonori; Yamaoka, Shiro; Uehara, Ryohei; Ozaki, Noriatsu; Ohashi, Akiyoshi; Albertsen, Mads; Nielsen, Per Halkjær; Nielsen, Jeppe Lund

    2016-06-01

    Candidate phylum Saccharibacteria (former TM7) are abundant and widespread in nature, but little is known about their ecophysiology and detailed phylogeny. In this study phylogeny, morphology and ecophysiology of Saccharibacteria were investigated in activated sludge from nine wastewater treatment plants (WWTPs) from Japan and Denmark using the full-cycle 16S rRNA approach in combination with microautoradiography (MAR) and fluorescence in situ hybridization (FISH). Phylogenetic analysis showed that Saccharibacteria from all WWTPs were evenly distributed within subdivision 1 and 3 and in a distinct phylogenetic clade. Three probes were designed for the distinct saccharibacterial groups, and revealed morphotypes representing thin filaments, thick filaments and rods/cocci. MAR-FISH results showed that most probe-defined Saccharibacteria utilized glucose under aerobic-, nitrate reducing- and anaerobic conditions. Some Saccharibacteria also utilized N-acetylglucosamine, oleic acid, amino acids and butyrate, which are not predicted from available genomes so far. In addition, some filamentous Saccharibacteria exhibited β-galactosidase and lipase activities determined using a combination of enzyme-labeled fluorescence and FISH (ELF-FISH). No uptake of acetate, propionate, pyruvate, glycerol and ethanol was observed. These results indicate that Saccharibacteria is a phylogenetically diverse group and play a role in the degradation of various organic compounds as well as sugar compounds under aerobic-, nitrate reducing- and anaerobic conditions. PMID:27090759

  5. Divergence Times and Phylogenetic Patterns of Sebacinales, a Highly Diverse and Widespread Fungal Lineage.

    Directory of Open Access Journals (Sweden)

    Sigisfredo Garnica

    Full Text Available Patterns of geographic distribution and composition of fungal communities are still poorly understood. Widespread occurrence in terrestrial ecosystems and the unique richness of interactions of Sebacinales with plants make them a target group to study evolutionary events in the light of nutritional lifestyle. We inferred diversity patterns, phylogenetic structures and divergence times of Sebacinales with respect to their nutritional lifestyles by integrating data from fossil-calibrated phylogenetic analyses. Relaxed molecular clock analyses indicated that Sebacinales originated late Permian within Basidiomycota, and their split into Sebacinaceae and Serendipitaceae nom. prov. likely occurred during the late Jurassic and the early Cretaceous, coinciding with major diversifications of land plants. In Sebacinaceae, diversification of species with ectomycorrhizal lifestyle presumably started during the Paleocene. Lineage radiations of the core group of ericoid and cavendishioid mycorrhizal Sebacinales started probably in the Eocene, coinciding with diversification events of their hosts. The diversification of Sebacinales with jungermannioid interactions started during the Oligocene, and occurred much later than the diversification of their hosts. Sebacinales communities associated either with ectomycorrhizal plants, achlorophyllous orchids, ericoid and cavendishioid Ericaceae or liverworts were phylogenetically clustered and globally distributed. Major Sebacinales lineage diversifications started after the continents had drifted apart. We also briefly discuss dispersal patterns of extant Sebacinales.

  6. Divergence Times and Phylogenetic Patterns of Sebacinales, a Highly Diverse and Widespread Fungal Lineage.

    Science.gov (United States)

    Garnica, Sigisfredo; Riess, Kai; Schön, Max E; Oberwinkler, Franz; Setaro, Sabrina D

    2016-01-01

    Patterns of geographic distribution and composition of fungal communities are still poorly understood. Widespread occurrence in terrestrial ecosystems and the unique richness of interactions of Sebacinales with plants make them a target group to study evolutionary events in the light of nutritional lifestyle. We inferred diversity patterns, phylogenetic structures and divergence times of Sebacinales with respect to their nutritional lifestyles by integrating data from fossil-calibrated phylogenetic analyses. Relaxed molecular clock analyses indicated that Sebacinales originated late Permian within Basidiomycota, and their split into Sebacinaceae and Serendipitaceae nom. prov. likely occurred during the late Jurassic and the early Cretaceous, coinciding with major diversifications of land plants. In Sebacinaceae, diversification of species with ectomycorrhizal lifestyle presumably started during the Paleocene. Lineage radiations of the core group of ericoid and cavendishioid mycorrhizal Sebacinales started probably in the Eocene, coinciding with diversification events of their hosts. The diversification of Sebacinales with jungermannioid interactions started during the Oligocene, and occurred much later than the diversification of their hosts. Sebacinales communities associated either with ectomycorrhizal plants, achlorophyllous orchids, ericoid and cavendishioid Ericaceae or liverworts were phylogenetically clustered and globally distributed. Major Sebacinales lineage diversifications started after the continents had drifted apart. We also briefly discuss dispersal patterns of extant Sebacinales. PMID:26938104

  7. The Role of the Phylogenetic Diversity Measure, PD, in Bio-informatics: Getting the Definition Right

    Directory of Open Access Journals (Sweden)

    Daniel P. Faith

    2006-01-01

    Full Text Available A recent paper in this journal (Faith and Baker, 2006 described bio-informatics challenges in the application of the PD (phylogenetic diversity measure of Faith (1992a, and highlighted the use of the root of the phylogenetic tree, as implied by the original definition of PD. A response paper (Crozier et al. 2006 stated that 1 the (Faith, 1992a PD definition did not include the use of the root of the tree, and 2 Moritz and Faith (1998 changed the PD definition to include the root. Both characterizations are here refuted. Examples from Faith (1992a,b document the link from the definition to the use of the root of the overall tree, and a survey of papers over the past 15 years by Faith and colleagues demonstrate that the stated PD definition has remained the same as that in the original 1992 study. PD’s estimation of biodiversity at the level of “feature diversity” is seen to have provided the original rationale for the measure’s consideration of the root of the phylogenetic tree.

  8. Phylogenetic diversity of rhizobial species and symbiovars nodulating Phaseolus vulgaris in Iran.

    Science.gov (United States)

    Rouhrazi, Kiomars; Khodakaramian, Gholam; Velázquez, Encarna

    2016-03-01

    The phylogenetic diversity of 29 rhizobial strains nodulating Phaseolus vulgaris in Iran was analysed on the basis of their core and symbiotic genes. These strains displayed five 16S rRNA-RFLP patterns and belong to eight ERIC-PCR clusters. The phylogenetic analyses of 16S rRNA, recA and atpD core genes allowed the identification of several strains as Rhizobium sophoriradicis, R. leguminosarum, R. tropici and Pararhizobium giardinii, whereas other strains represented a new phylogenetic lineage related to R. vallis. These strains and those identified as R. sophoriradicis and R. leguminosarum belong to the symbiovar phaseoli carrying the γ nodC allele distributed in P. vulgaris endosymbionts in America, Europe, Africa and Asia. The strain identified as R. tropici belongs to the symbiovar tropici carried by strains of R. tropici, R. leucaenae, R. lusitanum and R. freirei nodulating P. vulgaris in America, Africa and Asia. The strain identified as P. giardinii belongs to the symbiovar giardinii together with the type strain of this species nodulating P. vulgaris in France. It is remarkable that the recently described species R. sophoriradicis is worldwide distributed in P. vulgaris nodules carrying the γ nodC allele of symbiovar phaseoli harboured by rhizobia isolated in the American distribution centers of this legume. PMID:26832644

  9. Dengue in China: Comprehensive Phylogenetic Evaluation Reveals Evidence of Endemicity and Complex Genetic Diversity.

    Science.gov (United States)

    Chen, Rubing; Han, Guan-Zhu

    2016-01-01

    Despite the increasing threat of dengue outbreaks in China, it is still considered as an imported disease and its introduction and/or circulation patterns remain obscure. On the basis of the most extensive phylogenetic analysis to date, we showed highly complex genetic diversity of dengue viruses (DENVs) in south China with up to 20 different clades/lineages from multiple serotypes co-circulating in the same year. Despite that most of these clades/lineages were resulted from imported cases, evidence of local persistence of DENV serotype 1 (DENV-1) was observed, indicating its potential endemicity in Guangdong province. This study, therefore, provided an overview of DENV genetic diversity and evolutionary dynamics in China, which will be useful for developing policies to prevent and control future dengue outbreaks in China. PMID:26458780

  10. Phylogenetic niche conservatism explains an inverse latitudinal diversity gradient in freshwater arthropods

    Science.gov (United States)

    Morinière, Jérôme; van Dam, Matthew H.; Hawlitschek, Oliver; Bergsten, Johannes; Michat, Mariano C.; Hendrich, Lars; Ribera, Ignacio; Toussaint, Emmanuel F. A.; Balke, Michael

    2016-05-01

    The underlying mechanisms responsible for the general increase in species richness from temperate regions to the tropics remain equivocal. Many hypotheses have been proposed to explain this astonishing pattern but additional empirical studies are needed to shed light on the drivers at work. Here we reconstruct the evolutionary history of the cosmopolitan diving beetle subfamily Colymbetinae, the majority of which are found in the Northern hemisphere, hence exhibiting an inversed latitudinal diversity gradient. We reconstructed a dated phylogeny using 12 genes, to investigate the biogeographical history and diversification dynamics in the Colymbetinae. We aimed to identify the role that phylogenetic niche conservatism plays in the inversed diversification pattern seen in this group. Our results suggest that Colymbetinae originated in temperate climates, which supports the hypothesis that their distribution is the result of an ancestral adaptation to temperate environmental conditions rather than tropical origins, and that temperate niche conservatism can generate and/or maintain inverse latitudinal diversity gradients.

  11. Microbial communities in salt lakes: Phylogenetic diversity, metabolic diversity, and in situ activities

    OpenAIRE

    Oren, Aharon; Baxter, Bonnie K; Bart C Weimer

    2009-01-01

    A roundtable discussion was held on Monday, 12 May 2008, following the sessions on 'Microorganisms in Hypersaline Environments' at the 10th Conference on Salt Lake Research & 2008 FRIENDS of Great Salt Lake Issues Forum, University of Utah, Salt Lake City. Among the aspects discussed were: 1. The gap between our knowledge of the microorganisms isolated in culture and the true microbial diversity as apparent when using culture-independent techniques, in most cases based on the characterization...

  12. Relative roles of local disturbance, current climate and palaeoclimate in determining phylogenetic and functional diversity in Chinese forests

    DEFF Research Database (Denmark)

    Feng, Gang; Mi, Xiangcheng; Bøcher, Peder Klith;

    2014-01-01

    studied, their relative importance for other aspects of diversity, notably phylogenetic and functional diversity is so far little studied. Here, we link data from large Chinese forest plots to data on current and Last Glacial Maximum (LGM) climate as well as local disturbance regimes to study...... for light in determining the forest Hmax structure. In contrast, the LGM–present anomaly in temperature was the factor with the strongest explanatory power for phylogenetic diversity, with modern climate also important. Hence, local contemporary and regional historical factors have highly contrasting...

  13. Morphological, phylogenetic and physiological diversity of cyanobacteria in the hot springs of Zerka Ma

    Directory of Open Access Journals (Sweden)

    Aharon Oren

    2009-12-01

    Full Text Available The freshwater thermal springs of Zerka Ma'in, located in Jordan in the mountains of Moab east of the Dead Sea, are densely inhabited by cyanobacteria up to the highest temperature of 63°C. We have investigated the cyanobacterial diversity of these springs and their outflow channels by microscopic examination, culture-dependent and culture-independent phylogenetic analysis, and by physiological studies of selected isolates of special interest. Both unicellular and filamentous types of cyanobacteria are present, and we identified morphological types such as Thermosynechococcus, Chroogloeocystis, Fischerella (Mastigocladus, Scytonema (occurring as large masses at lower temperatures, and others. Although morphologically similar cyanobacteria have been identified in hot springs world-wide, the Zerka Ma’in strains were phylogenetically distinct based on 16S rRNA gene sequence analysis. Considerable diversity was detected also in the gene sequences of nifH (nitrogenase reductase, encoding one of the key enzymes involved in nitrogen fixation. Nitrogen fixation in a Mastigocladus isolate obtained from the springs was investigated in further depth. The heterocystous strain could fix nitrogen (as assayed by acetylene reduction at tem peratures up to 53°C.

  14. Relative roles of local disturbance, current climate and palaeoclimate in determining phylogenetic and functional diversity in Chinese forests

    OpenAIRE

    Feng, G.; Mi, X. C.; P. K. Bøcher; Mao, L. F.; Sandel, B.; Cao, M.; Ye, W. H.; Z. Q. Hao; H. D. Gong; Zhang, Y.T.; Zhao, X. H.; Jin, G. Z.; Ma, K. P.; J.-C. Svenning

    2013-01-01

    The main processes underlying the generation and maintenance of biodiversity include both local factors such as competition and abiotic filtering and regional forces such as palaeoclimate, speciation and dispersal. While the effects of regional and local drivers on species diversity are increasingly studied, their relative importance for other aspects of diversity, notably phylogenetic and functional diversity is so far little studied. Here, we link data from large Chinese forest plots to dat...

  15. Relative roles of local disturbance, current climate and paleoclimate in determining phylogenetic and functional diversity in Chinese forests

    OpenAIRE

    Feng, G.; Mi, X. C.; P. K. Bøcher; Mao, L. F.; Sandel, B.; Cao, M.; Ye, W. H.; Z. Q. Hao; H. D. Gong; Zhang, Y.T.; Zhao, X. H.; Jin, G. Z.; Ma, K. P.; J.-C. Svenning

    2014-01-01

    The main processes underlying the generation and maintenance of biodiversity include both local factors such as competition and abiotic filtering and regional forces such as paleoclimate, speciation and dispersal. While the effects of regional and local drivers on species diversity are increasingly studied, their relative importance for other aspects of diversity, notably phylogenetic and functional diversity is so far little studied. Here, we link data from large Chinese fo...

  16. Patterns of Phylogenetic Diversity of Subtropical Rainforest of the Great Sandy Region, Australia Indicate Long Term Climatic Refugia.

    Directory of Open Access Journals (Sweden)

    Marion G Howard

    Full Text Available Australia's Great Sandy Region is of international significance containing two World Heritage areas and patches of rainforest growing on white sand. Previous broad-scale analysis found the Great Sandy biogeographic subregion contained a significantly more phylogenetically even subset of species than expected by chance contrasting with rainforest on white sand in Peru. This study aimed to test the patterns of rainforest diversity and relatedness at a finer scale and to investigate why we may find different patterns of phylogenetic evenness compared with rainforests on white sands in other parts of the world. This study focussed on rainforest sites within the Great Sandy and surrounding areas in South East Queensland (SEQ, Australia. We undertook field collections, expanded our three-marker DNA barcode library of SEQ rainforest plants and updated the phylogeny to 95% of the SEQ rainforest flora. We sampled species composition of rainforest in fixed area plots from 100 sites. We calculated phylogenetic diversity (PD measures as well as species richness (SR for each rainforest community. These combined with site variables such as geology, were used to evaluate patterns and relatedness. We found that many rainforest communities in the Great Sandy area were significantly phylogenetically even at the individual site level consistent with a broader subregion analysis. Sites from adjacent areas were either not significant or were significantly phylogenetically clustered. Some results in the neighbouring areas were consistent with historic range expansions. In contrast with expectations, sites located on the oldest substrates had significantly lower phylogenetic diversity (PD. Fraser Island was once connected to mainland Australia, our results are consistent with a region geologically old enough to have continuously supported rainforest in refugia. The interface of tropical and temperate floras in part also explains the significant phylogenetic evenness

  17. Patterns of Phylogenetic Diversity of Subtropical Rainforest of the Great Sandy Region, Australia Indicate Long Term Climatic Refugia

    Science.gov (United States)

    Howard, Marion G.; McDonald, William J. F.; Forster, Paul I.; Kress, W. John; Erickson, David; Faith, Daniel P.; Shapcott, Alison

    2016-01-01

    Australia’s Great Sandy Region is of international significance containing two World Heritage areas and patches of rainforest growing on white sand. Previous broad-scale analysis found the Great Sandy biogeographic subregion contained a significantly more phylogenetically even subset of species than expected by chance contrasting with rainforest on white sand in Peru. This study aimed to test the patterns of rainforest diversity and relatedness at a finer scale and to investigate why we may find different patterns of phylogenetic evenness compared with rainforests on white sands in other parts of the world. This study focussed on rainforest sites within the Great Sandy and surrounding areas in South East Queensland (SEQ), Australia. We undertook field collections, expanded our three-marker DNA barcode library of SEQ rainforest plants and updated the phylogeny to 95% of the SEQ rainforest flora. We sampled species composition of rainforest in fixed area plots from 100 sites. We calculated phylogenetic diversity (PD) measures as well as species richness (SR) for each rainforest community. These combined with site variables such as geology, were used to evaluate patterns and relatedness. We found that many rainforest communities in the Great Sandy area were significantly phylogenetically even at the individual site level consistent with a broader subregion analysis. Sites from adjacent areas were either not significant or were significantly phylogenetically clustered. Some results in the neighbouring areas were consistent with historic range expansions. In contrast with expectations, sites located on the oldest substrates had significantly lower phylogenetic diversity (PD). Fraser Island was once connected to mainland Australia, our results are consistent with a region geologically old enough to have continuously supported rainforest in refugia. The interface of tropical and temperate floras in part also explains the significant phylogenetic evenness and higher than

  18. Phylogenetic Diversity of Vibrio cholerae Associated with Endemic Cholera in Mexico from 1991 to 2008

    Science.gov (United States)

    Choi, Seon Young; Rashed, Shah M.; Hasan, Nur A.; Alam, Munirul; Islam, Tarequl; Sadique, Abdus; Johura, Fatema-Tuz; Eppinger, Mark; Huq, Anwar; Cravioto, Alejandro

    2016-01-01

    ABSTRACT An outbreak of cholera occurred in 1991 in Mexico, where it had not been reported for more than a century and is now endemic. Vibrio cholerae O1 prototype El Tor and classical strains coexist with altered El Tor strains (1991 to 1997). Nontoxigenic (CTX−) V. cholerae El Tor dominated toxigenic (CTX+) strains (2001 to 2003), but V. cholerae CTX+ variant El Tor was isolated during 2004 to 2008, outcompeting CTX− V. cholerae. Genomes of six Mexican V. cholerae O1 strains isolated during 1991 to 2008 were sequenced and compared with both contemporary and archived strains of V. cholerae. Three were CTX+ El Tor, two were CTX− El Tor, and the remaining strain was a CTX+ classical isolate. Whole-genome sequence analysis showed the six isolates belonged to five distinct phylogenetic clades. One CTX− isolate is ancestral to the 6th and 7th pandemic CTX+ V. cholerae isolates. The other CTX− isolate joined with CTX− non-O1/O139 isolates from Haiti and seroconverted O1 isolates from Brazil and Amazonia. One CTX+ isolate was phylogenetically placed with the sixth pandemic classical clade and the V. cholerae O395 classical reference strain. Two CTX+ El Tor isolates possessing intact Vibrio seventh pandemic island II (VSP-II) are related to hybrid El Tor isolates from Mozambique and Bangladesh. The third CTX+ El Tor isolate contained West African-South American (WASA) recombination in VSP-II and showed relatedness to isolates from Peru and Brazil. Except for one isolate, all Mexican isolates lack SXT/R391 integrative conjugative elements (ICEs) and sensitivity to selected antibiotics, with one isolate resistant to streptomycin. No isolates were related to contemporary isolates from Asia, Africa, or Haiti, indicating phylogenetic diversity. PMID:26980836

  19. Molecular phylogenetics, species diversity, and biogeography of the Andean lizards of the genus Proctoporus (Squamata: Gymnophthalmidae).

    Science.gov (United States)

    Goicoechea, Noemí; Padial, José M; Chaparro, Juan C; Castroviejo-Fisher, Santiago; De la Riva, Ignacio

    2012-12-01

    The family Gymnophthalmidae comprises ca. 220 described species of Neotropical lizards distributed from southern Mexico to Argentina. It includes 36 genera, among them Proctoporus, which contains six currently recognized species occurring across the yungas forests and wet montane grasslands of the Amazonian versant of the Andes from central Peru to central Bolivia. Here, we investigate the phylogenetic relationships and species limits of Proctoporus and closely related taxa by analyzing 2121 base pairs of mitochondrial (12S, 16S, and ND4) and nuclear (c-mos) genes. Our taxon sampling of 92 terminals includes all currently recognized species of Proctoporus and 15 additional species representing the most closely related groups to the genus. Maximum parsimony, maximum likelihood and Bayesian phylogenetic analyses recovered a congruent, fully resolved, and strongly supported hypothesis of relationships that challenges previous phylogenetic hypotheses and classifications, and biogeographic scenarios. Our main results are: (i) discovery of a strongly supported clade that includes all species of Proctoporus and within which are nested the monotypic Opipeuter xestus (a genus that we consider a junior synonym of Proctoporus), and two species of Euspondylus, that are therefore transferred to Proctoporus; (ii) the paraphyly of Proctoporus bolivianus with respect to P. subsolanus, which is proposed as a junior synonym of P. bolivianus; (iii) the detection of seven divergent and reciprocally monophyletic lineages (five of them previously assigned to P. bolivianus) that are considered confirmed candidate species, which implies that more candidate species are awaiting formal description and naming than currently recognized species in the genus; (iv) rejection of the hypothesis that Proctoporus diversified following a south to north pattern parallel to the elevation of the Andes; (v) species diversity in Proctoporus is the result of in situ diversification through vicariance in

  20. Common biosynthetic origins for polycyclic tetramate macrolactams from phylogenetically diverse bacteria.

    Science.gov (United States)

    Blodgett, Joshua A V; Oh, Dong-Chan; Cao, Shugeng; Currie, Cameron R; Kolter, Roberto; Clardy, Jon

    2010-06-29

    A combination of small molecule chemistry, biosynthetic analysis, and genome mining has revealed the unexpected conservation of polycyclic tetramate macrolactam biosynthetic loci in diverse bacteria. Initially our chemical analysis of a Streptomyces strain associated with the southern pine beetle led to the discovery of frontalamides A and B, two previously undescribed members of this antibiotic family. Genome analyses and genetic manipulation of the producing organism led to the identification of the frontalamide biosynthetic gene cluster and several biosynthetic intermediates. The biosynthetic locus for the frontalamides' mixed polyketide/amino acid structure encodes a hybrid polyketide synthase nonribosomal peptide synthetase (PKS-NRPS), which resembles iterative enzymes known in fungi. No such mixed iterative PKS-NRPS enzymes have been characterized in bacteria. Genome-mining efforts revealed strikingly conserved frontalamide-like biosynthetic clusters in the genomes of phylogenetically diverse bacteria ranging from proteobacteria to actinomycetes. Screens for environmental actinomycete isolates carrying frontalamide-like biosynthetic loci led to the isolation of a number of positive strains, the majority of which produced candidate frontalamide-like compounds under suitable growth conditions. These results establish the prevalence of frontalamide-like gene clusters in diverse bacterial types, with medicinally important Streptomyces species being particularly enriched. PMID:20547882

  1. Phylogenetic diversity, composition and distribution of bacterioplankton community in the Dongjiang River, China.

    Science.gov (United States)

    Liu, Zhenghui; Huang, Shaobin; Sun, Guoping; Xu, Zhencheng; Xu, Meiying

    2012-04-01

    Bacterioplankton community compositions in the Dongjiang River were characterized using denaturing gradient gel electrophoresis (DGGE) and 16S rRNA gene clone library construction. Water samples in nine different sites were taken along the mainstem and three tributaries. In total, 24 bands from DGGE gels and 406 clones from the libraries were selected and sequenced, subsequently analyzed for the bacterial diversity and composition of those microbial communities. Bacterial 16S rRNA gene sequences from freshwater bacteria exhibited board phylogenetic diversity, including sequences representing the Alphaproteobacteria, Betaproteobacteria, Gammaproteobacteria, Actinobacteria, Bacteriodetes, Verrucomicrobia, and candidate division TM7. Members of Betaproteobacteria group were the most dominant in all sampling sites, followed by Gammaproteobacteria, Alphaproteobacteria, and Actinobacteria. DGGE profiles and the ∫-LIBSHUFF analysis revealed similar patterns of bacterial diversity among most sampling sites, while spatial distribution variances existed in all sites along the river basin. Statistical analysis showed that bacterial species distribution strongly correlated with environmental variables, such as nitrate and ammonia, suggesting that nitrogen nutrients may shape the microbial community structure and composition in the Dongjiang River. This study had important implications for the comparison with other rivers elsewhere and contributed to the growing data set on the factors that structure bacterial communities in freshwater ecosystems. PMID:22133045

  2. Structural similarities between biogenic uraninites produced by phylogenetically and metabolically diverse bacteria

    International Nuclear Information System (INIS)

    While the product of microbial uranium reduction is often reported to be 'UO2', a comprehensive characterization including stoichiometry and unit cell determination is available for only one Shewanella species. Here, we compare the products of batch uranyl reduction by a collection of dissimilatory metal- and sulfate-reducing bacteria of the genera Shewanella, Geobacter, Anaeromyxobacter, and Desulfovibrio under similar laboratory conditions. Our results demonstrate that U(VI) bioreduction by this assortment of commonly studied, environmentally relevant bacteria leads to the precipitation of uraninite with a composition between UO2.00 and UO2.075, regardless of phylogenetic or metabolic diversity. Coupled analyses, including electron microscopy, X-ray absorption spectroscopy, and powder diffraction, confirm that structurally and chemically analogous uraninite solids are produced. These biogenic uraninites have particle diameters of about 2-3 nm and lattice constants consistent with UO2.0 and exhibit a high degree of intermediate-range order. Results indicate that phylogenetic and metabolic variability within delta- and gamma-proteobacteria has little effect on nascent biouraninite structure or crystal size under the investigated conditions.

  3. A Large and Phylogenetically Diverse Class of Type 1 Opsins Lacking a Canonical Retinal Binding Site.

    Science.gov (United States)

    Becker, Erin A; Yao, Andrew I; Seitzer, Phillip M; Kind, Tobias; Wang, Ting; Eigenheer, Rich; Shao, Katie S Y; Yarov-Yarovoy, Vladimir; Facciotti, Marc T

    2016-01-01

    Opsins are photosensitive proteins catalyzing light-dependent processes across the tree of life. For both microbial (type 1) and metazoan (type 2) opsins, photosensing depends upon covalent interaction between a retinal chromophore and a conserved lysine residue. Despite recent discoveries of potential opsin homologs lacking this residue, phylogenetic dispersal and functional significance of these abnormal sequences have not yet been investigated. We report discovery of a large group of putatively non-retinal binding opsins, present in a number of fungal and microbial genomes and comprising nearly 30% of opsins in the Halobacteriacea, a model clade for opsin photobiology. We report phylogenetic analyses, structural modeling, genomic context analysis and biochemistry, to describe the evolutionary relationship of these recently described proteins with other opsins, show that they are expressed and do not bind retinal in a canonical manner. Given these data, we propose a hypothesis that these abnormal opsin homologs may represent a novel family of sensory opsins which may be involved in taxis response to one or more non-light stimuli. If true, this finding would challenge our current understanding of microbial opsins as a light-specific sensory family, and provides a potential analogy with the highly diverse signaling capabilities of the eukaryotic G-protein coupled receptors (GPCRs), of which metazoan type 2 opsins are a light-specific sub-clade. PMID:27327432

  4. A Large and Phylogenetically Diverse Class of Type 1 Opsins Lacking a Canonical Retinal Binding Site.

    Directory of Open Access Journals (Sweden)

    Erin A Becker

    Full Text Available Opsins are photosensitive proteins catalyzing light-dependent processes across the tree of life. For both microbial (type 1 and metazoan (type 2 opsins, photosensing depends upon covalent interaction between a retinal chromophore and a conserved lysine residue. Despite recent discoveries of potential opsin homologs lacking this residue, phylogenetic dispersal and functional significance of these abnormal sequences have not yet been investigated. We report discovery of a large group of putatively non-retinal binding opsins, present in a number of fungal and microbial genomes and comprising nearly 30% of opsins in the Halobacteriacea, a model clade for opsin photobiology. We report phylogenetic analyses, structural modeling, genomic context analysis and biochemistry, to describe the evolutionary relationship of these recently described proteins with other opsins, show that they are expressed and do not bind retinal in a canonical manner. Given these data, we propose a hypothesis that these abnormal opsin homologs may represent a novel family of sensory opsins which may be involved in taxis response to one or more non-light stimuli. If true, this finding would challenge our current understanding of microbial opsins as a light-specific sensory family, and provides a potential analogy with the highly diverse signaling capabilities of the eukaryotic G-protein coupled receptors (GPCRs, of which metazoan type 2 opsins are a light-specific sub-clade.

  5. Archaeal Community Changes Associated with Cultivation of Amazon Forest Soil with Oil Palm.

    Science.gov (United States)

    Tupinambá, Daiva Domenech; Cantão, Maurício Egídio; Costa, Ohana Yonara Assis; Bergmann, Jessica Carvalho; Kruger, Ricardo Henrique; Kyaw, Cynthia Maria; Barreto, Cristine Chaves; Quirino, Betania Ferraz

    2016-01-01

    This study compared soil archaeal communities of the Amazon forest with that of an adjacent area under oil palm cultivation by 16S ribosomal RNA gene pyrosequencing. Species richness and diversity were greater in native forest soil than in the oil palm-cultivated area, and 130 OTUs (13.7%) were shared between these areas. Among the classified sequences, Thaumarchaeota were predominant in the native forest, whereas Euryarchaeota were predominant in the oil palm-cultivated area. Archaeal species diversity was 1.7 times higher in the native forest soil, according to the Simpson diversity index, and the Chao1 index showed that richness was five times higher in the native forest soil. A phylogenetic tree of unclassified Thaumarchaeota sequences showed that most of the OTUs belong to Miscellaneous Crenarchaeotic Group. Several archaeal genera involved in nutrient cycling (e.g., methanogens and ammonia oxidizers) were identified in both areas, but significant differences were found in the relative abundances of Candidatus Nitrososphaera and unclassified Soil Crenarchaeotic Group (prevalent in the native forest) and Candidatus Nitrosotalea and unclassified Terrestrial Group (prevalent in the oil palm-cultivated area). More studies are needed to culture some of these Archaea in the laboratory so that their metabolism and physiology can be studied. PMID:27006640

  6. Archaeal Community Changes Associated with Cultivation of Amazon Forest Soil with Oil Palm

    Science.gov (United States)

    Tupinambá, Daiva Domenech; Cantão, Maurício Egídio; Costa, Ohana Yonara Assis; Bergmann, Jessica Carvalho; Kruger, Ricardo Henrique; Kyaw, Cynthia Maria; Barreto, Cristine Chaves; Quirino, Betania Ferraz

    2016-01-01

    This study compared soil archaeal communities of the Amazon forest with that of an adjacent area under oil palm cultivation by 16S ribosomal RNA gene pyrosequencing. Species richness and diversity were greater in native forest soil than in the oil palm-cultivated area, and 130 OTUs (13.7%) were shared between these areas. Among the classified sequences, Thaumarchaeota were predominant in the native forest, whereas Euryarchaeota were predominant in the oil palm-cultivated area. Archaeal species diversity was 1.7 times higher in the native forest soil, according to the Simpson diversity index, and the Chao1 index showed that richness was five times higher in the native forest soil. A phylogenetic tree of unclassified Thaumarchaeota sequences showed that most of the OTUs belong to Miscellaneous Crenarchaeotic Group. Several archaeal genera involved in nutrient cycling (e.g., methanogens and ammonia oxidizers) were identified in both areas, but significant differences were found in the relative abundances of Candidatus Nitrososphaera and unclassified Soil Crenarchaeotic Group (prevalent in the native forest) and Candidatus Nitrosotalea and unclassified Terrestrial Group (prevalent in the oil palm-cultivated area). More studies are needed to culture some of these Archaea in the laboratory so that their metabolism and physiology can be studied. PMID:27006640

  7. Phylogenetic and metabolic diversity of Planctomycetes from anaerobic, sulfide- and sulfur-rich Zodletone Spring, Oklahoma.

    Science.gov (United States)

    Elshahed, Mostafa S; Youssef, Noha H; Luo, Qingwei; Najar, Fares Z; Roe, Bruce A; Sisk, Tracy M; Bühring, Solveig I; Hinrichs, Kai-Uwe; Krumholz, Lee R

    2007-08-01

    We investigated the phylogenetic diversity and metabolic capabilities of members of the phylum Planctomycetes in the anaerobic, sulfide-saturated sediments of a mesophilic spring (Zodletone Spring) in southwestern Oklahoma. Culture-independent analyses of 16S rRNA gene sequences generated using Planctomycetes-biased primer pairs suggested that an extremely diverse community of Planctomycetes is present at the spring. Although sequences that are phylogenetically affiliated with cultured heterotrophic Planctomycetes were identified, the majority of the sequences belonged to several globally distributed, as-yet-uncultured Planctomycetes lineages. Using complex organic media (aqueous extracts of the spring sediments and rumen fluid), we isolated two novel strains that belonged to the Pirellula-Rhodopirellula-Blastopirellula clade within the Planctomycetes. The two strains had identical 16S rRNA gene sequences, and their closest relatives were isolates from Kiel Fjord (Germany), Keauhou Beach (HI), a marine aquarium, and tissues of marine organisms (Aplysina sp. sponges and postlarvae of the giant tiger prawn Penaeus monodon). The closest recognized cultured relative of strain Zi62 was Blastopirellula marina (93.9% sequence similarity). Detailed characterization of strain Zi62 revealed its ability to reduce elemental sulfur to sulfide under anaerobic conditions, as well as its ability to produce acids from sugars; both characteristics may potentially allow strain Zi62 to survive and grow in the anaerobic, sulfide- and sulfur-rich environment at the spring source. Overall, this work indicates that anaerobic metabolic abilities are widely distributed among all major Planctomycetes lineages and suggests carbohydrate fermentation and sulfur reduction as possible mechanisms employed by heterotrophic Planctomycetes for growth and survival under anaerobic conditions. PMID:17545322

  8. Panorama phylogenetic diversity and distribution of type A influenza viruses based on their six internal gene sequences

    Directory of Open Access Journals (Sweden)

    Shen Chao-Jian

    2009-09-01

    Full Text Available Abstract Background Type A influenza viruses are important pathogens of humans, birds, pigs, horses and some marine mammals. The viruses have evolved into multiple complicated subtypes, lineages and sublineages. Recently, the phylogenetic diversity of type A influenza viruses from a whole view has been described based on the viral external HA and NA gene sequences, but remains unclear in terms of their six internal genes (PB2, PB1, PA, NP, MP and NS. Methods In this report, 2798 representative sequences of the six viral internal genes were selected from GenBank using the web servers in NCBI Influenza Virus Resource. Then, the phylogenetic relationships among the representative sequences were calculated using the software tools MEGA 4.1 and RAxML 7.0.4. Lineages and sublineages were classified mainly according to topology of the phylogenetic trees and distribution of the viruses in hosts, regions and time. Results The panorama phylogenetic trees of the six internal genes of type A influenza viruses were constructed. Lineages and sublineages within the type based on the six internal genes were classified and designated by a tentative universal numerical nomenclature system. The diversity of influenza viruses circulating in different regions, periods, and hosts based on the panorama trees was analyzed. Conclusion This study presents the first whole views to the phylogenetic diversity and distribution of type A influenza viruses based on their six internal genes. It also proposes a tentative universal nomenclature system for the viral lineages and sublineages. These can be a candidate framework to generalize the history and explore the future of the viruses, and will facilitate future scientific communications on the phylogenetic diversity and evolution of the viruses. In addition, it provides a novel phylogenetic view (i.e. the whole view to recognize the viruses including the origin of the pandemic A(H1N1 influenza viruses.

  9. Analysis of genetic diversity and phylogenetic relationships among red jungle fowls and Chinese domestic fowls

    Institute of Scientific and Technical Information of China (English)

    BAO WenBin; CHEN GuoHong; LI BiChun; WU XinSheng; SHU JingTing; WU ShengLong; XU Qi; Steffen WEIGEND

    2008-01-01

    Genetic diversity and phylogenetic relationships among 568 individuals of two red jungle fowl subspe-cies (Gallus gallus spadiceus in China and Gallus gallus gallus in Thailand) and 14 Chinese domestic chicken breeds were evaluated with 29 microstaellite loci, the genetic variability within population and genetic differentiation among population were estimated, and then genetic diversity and phylogenetic relationships were analyzed among red jungle fowls and Chinese domestic fowls. A total of 286 alleles were detected in 16 population with 29 microsatellite markers and the average number of the alleles observed in 29 microsatellite loci was 9.86±6.36. The overall expected heterozygosity of all population was 0.6708±0.0251, and the number of population deviated from Hardy-Weinberg equilibrium per locus ranged from 0 to 7. In the whole population, the average of genetic differentiation among population, measured as FST value, was 16.7% (P<0.001), and all loci contributed significantly (P<0.001) to this differentiation. It can also be seen that the deficit of heterozygotes was very high (0.015) (P<0.01). Reynolds' distance values varied between 0.036 (Xiaoshan chicken-Luyuan chicken pair) and 0.330 (G gallus gallus-Gushi chicken pair). The Nm value ranged from 0.533 (between G gallus gallus and Gushi chicken) to 5.833 (between Xiaoshan chicken and Luyuan chicken). An unrooted consensus tree was constructed using the neighbour-joining method and the Reynolds' genetic distance. The heavy-body sized chicken breeds, Luyuan chicken, Xiaoshan chicken, Beijing Fatty chicken, Henan Game chicken, Huainan Partridge and Langshan chicken formed one branch, and it had a close genetic relationship between Xiaoshan chicken-Luyuan chicken pair and Chahua chicken-Tibetan chicken pair. Chahua chicken and Tibetan chicken had closer genetic relationship with these two subspecies of red jungle fowl than other domestic chicken breeds. G gallus spadiceus showed closer phylogenetic

  10. Towards a better understanding of Apis mellifera and Varroa destructor microbiomes: introducing 'phyloh' as a novel phylogenetic diversity analysis tool.

    Science.gov (United States)

    Sandionigi, A; Vicario, S; Prosdocimi, E M; Galimberti, A; Ferri, E; Bruno, A; Balech, B; Mezzasalma, V; Casiraghi, M

    2015-07-01

    The study of diversity in biological communities is an intriguing field. Huge amount of data are nowadays available (provided by the innovative DNA sequencing techniques), and management, analysis and display of results are not trivial. Here, we propose for the first time the use of phylogenetic entropy as a measure of bacterial diversity in studies of microbial community structure. We then compared our new method (i.e. the web tool phyloh) for partitioning phylogenetic diversity with the traditional approach in diversity analyses of bacteria communities. We tested phyloh to characterize microbiome in the honeybee (Apis mellifera, Insecta: Hymenoptera) and its parasitic mite varroa (Varroa destructor, Arachnida: Parasitiformes). The rationale is that the comparative analysis of honeybee and varroa microbiomes could open new perspectives concerning the role of the parasites on honeybee colonies health. Our results showed a dramatic change of the honeybee microbiome when varroa occurs, suggesting that this parasite is able to influence host microbiome. Among the different approaches used, only the entropy method, in conjunction with phylogenetic constraint as implemented in phyloh, was able to discriminate varroa microbiome from that of parasitized honeybees. In conclusion, we foresee that the use of phylogenetic entropy could become a new standard in the analyses of community structure, in particular to prove the contribution of each biological entity to the overall diversity. PMID:25367306

  11. Archaeal extrachromosomal genetic elements

    DEFF Research Database (Denmark)

    Wang, Haina; Peng, Nan; Shah, Shiraz Ali;

    2015-01-01

    viruses and plasmids. In particular, it has been suggested that ECE-host interactions have shaped the coevolution of ECEs and their archaeal hosts. Furthermore, archaeal hosts have developed defense systems, including the innate restriction-modification (R-M) system and the adaptive CRISPR (clustered...

  12. Genetic diversity and phylogenetic relationships in local cattle breeds of Senegal based on autosomal microsatellite markers

    Directory of Open Access Journals (Sweden)

    Ndèye Penda Ndiaye

    2015-08-01

    Full Text Available Aim: In Senegal, uncontrolled cross-breeding of cattle breeds and changes in production systems are assumed to lead to an increase of gene flow between populations. This might constitute a relevant threat to livestock improvement. Therewith, this study was carried out to assess the current genetic diversity and the phylogenetic relationships of the four native Senegalese cattle breeds (Gobra zebu, Maure zebu, Djakoré, and N’Dama. Methods: Genomic DNA was isolated from blood samples of 120 unrelated animals collected from three agro-ecological areas of Senegal according to their phenotypic traits. Genotyping was done using 11 specific highly polymorphic microsatellite makers recommended by Food and Agriculture Organization. The basic measures of genetic variation and phylogenetic trees were computed using bioinformatics’ software. Results: A total of 115 alleles were identified with a number of alleles (Na at one locus ranging from 6 to 16. All loci were polymorphic with a mean polymorphic information content of 0.76. The mean allelic richness (Rs lay within the narrow range of 5.14 in N’Dama taurine to 6.10 in Gobra zebu. While, the expected heterozygosity (HE per breed was high in general with an overall mean of 0.76±0.04. Generally, the heterozygote deficiency (FIS of 0.073±0.026 was relatively due to inbreeding among these cattle breeds or the occurrence of population substructure. The high values of allelic and gene diversity showed that Senegalese native cattle breeds represented an important reservoir of genetic variation. The genetic distances and clustering trees concluded that the N’Dama cattle were most distinct among the investigated cattle populations. So, the principal component analyses showed qualitatively that there was an intensive genetic admixture between the Gobra zebu and Maure zebu breeds. Conclusions: The broad genetic diversity in Senegalese cattle breeds will allow for greater opportunities for improvement of

  13. Conservation Actions Based on Red Lists Do Not Capture the Functional and Phylogenetic Diversity of Birds in Brazil

    OpenAIRE

    Hidasi-Neto, José; Loyola, Rafael Dias; Cianciaruso, Marcus Vinicius

    2013-01-01

    Red Lists of threatened species play a critical role in conservation science and practice. However, policy-making based on Red Lists ignores ecological and evolutionary consequences of losing biodiversity because these lists focus on species alone. To decide if relying on Red Lists alone can help to conserve communities’ functional (FD) and phylogenetic (PD) diversity, it is useful to evaluate whether Red List categories represent species with diverse ecological traits and evolutionary histor...

  14. Temporal Dynamics of Active Prokaryotic Nitrifiers and Archaeal Communities from River to Sea.

    Science.gov (United States)

    Hugoni, Mylène; Agogué, Hélène; Taib, Najwa; Domaizon, Isabelle; Moné, Anne; Galand, Pierre E; Bronner, Gisèle; Debroas, Didier; Mary, Isabelle

    2015-08-01

    To test if different niches for potential nitrifiers exist in estuarine systems, we assessed by pyrosequencing the diversity of archaeal gene transcript markers for taxonomy (16S ribosomal RNA (rRNA)) during an entire year along a salinity gradient in surface waters of the Charente estuary (Atlantic coast, France). We further investigated the potential for estuarine prokaryotes to oxidize ammonia and hydrolyze urea by quantifying thaumarchaeal amoA and ureC and bacterial amoA transcripts. Our results showed a succession of different nitrifiers from river to sea with bacterial amoA transcripts dominating in the freshwater station while archaeal transcripts were predominant in the marine station. The 16S rRNA sequence analysis revealed that Thaumarchaeota marine group I (MGI) were the most abundant overall but other archaeal groups like Methanosaeta were also potentially active in winter (December-March) and Euryarchaeota marine group II (MGII) were dominant in seawater in summer (April-August). Each station also contained different Thaumarchaeota MGI phylogenetic clusters, and the clusters' microdiversity was associated to specific environmental conditions suggesting the presence of ecotypes adapted to distinct ecological niches. The amoA and ureC transcript dynamics further indicated that some of the Thaumarchaeota MGI subclusters were involved in ammonia oxidation through the hydrolysis of urea. Our findings show that ammonia-oxidizing Archaea and Bacteria were adapted to contrasted conditions and that the Thaumarchaeota MGI diversity probably corresponds to distinct metabolisms or life strategies. PMID:25851445

  15. Phylogenetic diversity of actinomycetes cultured from coastal multipond solar saltern in Tuticorin, India

    OpenAIRE

    Jose, Polpass Arul; Jebakumar, Solomon Robinson David

    2012-01-01

    Background Hypersaline solar salterns are extreme environments in many tropical and subtropical regions throughout the world. In India, there are several coastal solar salterns along with the coastal line of the Bay of Bengal and Arabian Sea and inland solar salterns around Sambhar saltlake, from which sodium chloride is obtained for human consumption and industrial needs. Studies on characterization of such coastal and inland solar salterns are scarce and both the bacterial and archaeal dive...

  16. Evaluating methods for isolating total RNA and predicting the success of sequencing phylogenetically diverse plant transcriptomes.

    Directory of Open Access Journals (Sweden)

    Marc T J Johnson

    Full Text Available Next-generation sequencing plays a central role in the characterization and quantification of transcriptomes. Although numerous metrics are purported to quantify the quality of RNA, there have been no large-scale empirical evaluations of the major determinants of sequencing success. We used a combination of existing and newly developed methods to isolate total RNA from 1115 samples from 695 plant species in 324 families, which represents >900 million years of phylogenetic diversity from green algae through flowering plants, including many plants of economic importance. We then sequenced 629 of these samples on Illumina GAIIx and HiSeq platforms and performed a large comparative analysis to identify predictors of RNA quality and the diversity of putative genes (scaffolds expressed within samples. Tissue types (e.g., leaf vs. flower varied in RNA quality, sequencing depth and the number of scaffolds. Tissue age also influenced RNA quality but not the number of scaffolds ≥ 1000 bp. Overall, 36% of the variation in the number of scaffolds was explained by metrics of RNA integrity (RIN score, RNA purity (OD 260/230, sequencing platform (GAIIx vs HiSeq and the amount of total RNA used for sequencing. However, our results show that the most commonly used measures of RNA quality (e.g., RIN are weak predictors of the number of scaffolds because Illumina sequencing is robust to variation in RNA quality. These results provide novel insight into the methods that are most important in isolating high quality RNA for sequencing and assembling plant transcriptomes. The methods and recommendations provided here could increase the efficiency and decrease the cost of RNA sequencing for individual labs and genome centers.

  17. Phylogenetic Diversity of Young Ocean Crust at the East Pacific Rise 9° N

    Science.gov (United States)

    Santelli, C. M.; Bach, W.; Rogers, D. R.; Edwards, K. J.

    2004-12-01

    Numerous studies show increasing evidence for a significant biosphere in oceanic lithosphere. Geochemical modeling suggests that most biological activity at or below the seafloor occurs in young crust (microbial activity, molecular microbiological data is required to corroborate these morphological and chemical observations. The application of molecular techniques to old ocean crust, however, can be difficult because of issues such as low cell density, contamination, and sluggish activity. Hence, studies on young ocean crust may provide insight and constraints on processes that could also apply to older crust. In this study, we have investigated the initial colonization of very young mid-ocean ridge basalt by endolithic microorganisms, and the changes in microbial diversity as a result of increasing rock alteration. Seafloor basalt samples were collected during RV Atlantis cruise AT11-7 in February 2004, from the East Pacific Rise (EPR) between 9° 28'N and 9° 50'N. Samples representing various flow morphologies, glass contents, and ages (up to ˜20 kyrs) were collected by DSV Alvin and brought to the surface in bioboxes. All basalts contain glass that ranges from very fresh to slightly altered with Fe-oxidation rims and/or Mn-oxide crusts. Total community DNA was successfully extracted from glass samples representative of a variety of alteration states. Clone libraries were constructed from PCR products of 16S rRNA genes using bacterial primers. Approximately 90 randomly selected clones from each library were sequenced. Phylogenetic analyses will indicate the overall diversity of young ocean crust and will help determine the succession of microorganisms colonizing the rock with increasing alteration. These results may also give us a better indication of the physiology of these microorganisms. Ultimately, this information will provide more accurate estimates of the impact of microbial activity in important geochemical processes such as the evolution of crustal

  18. Actinomycetes from red sea sponges: Sources for chemical and phylogenetic diversity

    KAUST Repository

    Abdelmohsen, Usama Ramadan

    2014-05-12

    The diversity of actinomycetes associated with marine sponges collected off Fsar Reef (Saudi Arabia) was investigated in the present study. Forty-seven actinomycetes were cultivated and phylogenetically identified based on 16S rRNA gene sequencing and were assigned to 10 different actinomycete genera. Eight putatively novel species belonging to genera Kocuria, Mycobacterium, Nocardia, and Rhodococcus were identified based on sequence similarity values below 98.2% to other 16S rRNA gene sequences available in the NCBI database. PCR-based screening for biosynthetic genes including type I and type II polyketide synthases (PKS-I, PKS-II) as well as nonribosomal peptide synthetases (NRPS) showed that 20 actinomycete isolates encoded each at least one type of biosynthetic gene. The organic extracts of nine isolates displayed bioactivity against at least one of the test pathogens, which were Gram-positive and Gram-negative bacteria, fungi, human parasites, as well as in a West Nile Virus protease enzymatic assay. These results emphasize that marine sponges are a prolific resource for novel bioactive actinomycetes with potential for drug discovery. 2014 by the authors; licensee MDPI.

  19. Actinomycetes from Red Sea Sponges: Sources for Chemical and Phylogenetic Diversity

    Directory of Open Access Journals (Sweden)

    Usama Ramadan Abdelmohsen

    2014-05-01

    Full Text Available The diversity of actinomycetes associated with marine sponges collected off Fsar Reef (Saudi Arabia was investigated in the present study. Forty-seven actinomycetes were cultivated and phylogenetically identified based on 16S rRNA gene sequencing and were assigned to 10 different actinomycete genera. Eight putatively novel species belonging to genera Kocuria, Mycobacterium, Nocardia, and Rhodococcus were identified based on sequence similarity values below 98.2% to other 16S rRNA gene sequences available in the NCBI database. PCR-based screening for biosynthetic genes including type I and type II polyketide synthases (PKS-I, PKS-II as well as nonribosomal peptide synthetases (NRPS showed that 20 actinomycete isolates encoded each at least one type of biosynthetic gene. The organic extracts of nine isolates displayed bioactivity against at least one of the test pathogens, which were Gram-positive and Gram-negative bacteria, fungi, human parasites, as well as in a West Nile Virus protease enzymatic assay. These results emphasize that marine sponges are a prolific resource for novel bioactive actinomycetes with potential for drug discovery.

  20. Phylogenetic diversity of endophytic leaf fungus isolates from the medicinal tree Trichilia elegans (Meliaceae).

    Science.gov (United States)

    Rhoden, S A; Garcia, A; Rubin Filho, C J; Azevedo, J L; Pamphile, J A

    2012-01-01

    Various types of organisms, mainly fungi and bacteria, live within vegetal organs and tissues, without causing damage to the plant. These microorganisms, which are called endophytes, can be useful for biological control and plant growth promotion; bioactive compounds from these organisms may have medical and pharmaceutical applications. Trichilia elegans (Meliaceae) is a native tree that grows abundantly in several regions of Brazil. Preparations using the leaves, seeds, bark, and roots of many species of the Meliaceae family have been widely used in traditional medicine, and some members of the Trichilia genus are used in Brazilian popular medicine. We assessed the diversity of endophytic fungi from two wild specimens of T. elegans, collected from a forest remnant, by sequencing ITS1-5.8S-ITS2 of rDNA of the isolates. The fungi were isolated and purified; 97 endophytic fungi were found; they were separated into 17 morpho-groups. Of the 97 endophytic fungi, four genera (Phomopsis, Diaporthe, Dothideomycete, and Cordyceps) with 11 morpho-groups were identified. Phomopsis was the most frequent genus among the identified endophytes. Phylogenetic analysis showed two major clades: Sordariomycetes, which includes three genera, Phomopsis, Diaporthe, and Cordyceps, and the clade Dothideomycetes, which was represented by the order Pleosporales. PMID:22782630

  1. Phylogenetically diverse AM fungi from Ecuador strongly improve seedling growth of native potential crop trees.

    Science.gov (United States)

    Schüßler, Arthur; Krüger, Claudia; Urgiles, Narcisa

    2016-04-01

    In many deforested regions of the tropics, afforestation with native tree species could valorize a growing reservoir of degraded, previously overused and abandoned land. The inoculation of tropical tree seedlings with arbuscular mycorrhizal fungi (AM fungi) can improve tree growth and viability, but efficiency may depend on plant and AM fungal genotype. To study such effects, seven phylogenetically diverse AM fungi, native to Ecuador, from seven genera and a non-native AM fungus (Rhizophagus irregularis DAOM197198) were used to inoculate the tropical potential crop tree (PCT) species Handroanthus chrysanthus (synonym Tabebuia chrysantha), Cedrela montana, and Heliocarpus americanus. Twenty-four plant-fungus combinations were studied in five different fertilization and AMF inoculation treatments. Numerous plant growth parameters and mycorrhizal root colonization were assessed. The inoculation with any of the tested AM fungi improved seedling growth significantly and in most cases reduced plant mortality. Plants produced up to threefold higher biomass, when compared to the standard nursery practice. AM fungal inoculation alone or in combination with low fertilization both outperformed full fertilization in terms of plant growth promotion. Interestingly, root colonization levels for individual fungi strongly depended on the host tree species, but surprisingly the colonization strength did not correlate with plant growth promotion. The combination of AM fungal inoculation with a low dosage of slow release fertilizer improved PCT seedling performance strongest, but also AM fungal treatments without any fertilization were highly efficient. The AM fungi tested are promising candidates to improve management practices in tropical tree seedling production. PMID:26260945

  2. Elucidating further phylogenetic diversity among the Defluviicoccus-related glycogen-accumulating organisms in activated sludge.

    Science.gov (United States)

    McIlroy, Simon; Seviour, Robert J

    2009-12-01

    Glycogen-accumulating organisms (GAO) are thought to out-compete the polyphosphate-accumulating organisms (PAO) in activated sludge communities removing phosphate (P). Two GAO groups are currently recognized, the gammaproteobacterial Candidatus'Competibacter phosphatis', and the alphaproteobacterial Defluviicoccus vanus-related tetrad forming organisms (TFOs). Both are phylogenetically diverse based on their 16S rRNA sequences, with the latter currently considered to contain members falling into three distinct clusters. This paper identifies members of an additional fourth Defluviicoccus cluster from 16S rRNA gene clone library data obtained from a laboratory-scale activated sludge plant community removing P, and details FISH probes designed against them. Probe DF181A was designed to target a single sequence and DF181B designed against the remaining sequences in the cluster. Cells hybridizing with these probes in the biomass samples tested always appeared as either TFOs or in large clusters of small cocci. Members of the Defluviicoccus-related organisms were commonly found in full-scale wastewater treatments plants, sometimes as a dominant population. PMID:23765935

  3. Cultivated Beggiatoa spp. define the phylogenetic root of morphologically diverse, noncultured, vacuolate sulfur bacteria.

    Science.gov (United States)

    Ahmad, Azeem; Kalanetra, Karen M; Nelson, Douglas C

    2006-06-01

    Within the last 10 years, numerous SSU rRNA sequences have been collected from natural populations of conspicuous, vacuolate, colorless sulfur bacteria, which form a phylogenetically cohesive cluster (large-vacuolate sulfur bacteria clade) in the gamma-Proteobacteria. Currently, this clade is composed of four named or de facto genera: all known Thioploca and Thiomargarita strains, all vacuolate Beggiatoa strains, and several strains of vacuolate, attached filaments, which bear a superficial similarity to Thiothrix. Some of these vacuolate bacteria accumulate nitrate for respiratory purposes. This clade encompasses the largest known prokaryotic cells (Thiomargarita namibiensis) and several strains that are important in the global marine sulfur cycle. Here, we report additional sequences from five pure culture strains of Beggiatoa spp., including the only two cultured marine strains (nonvacuolate), which firmly establish the root of this vacuolate clade. Each of several diverse metabolic motifs, including obligate and facultative chemolithoautotrophy, probable mixotrophy, and seemingly strict organoheterotrophy, is represented in at least one of the nonvacuolate strains that root the vacuolate clade. Because the genus designation Beggiatoa is interspersed throughout the vacuolate clade along with other recognized or de facto genera, the need for taxonomic revision is clear. PMID:16788728

  4. Phylogenetically Diverse Burkholderia Associated with Midgut Crypts of Spurge Bugs, Dicranocephalus spp. (Heteroptera: Stenocephalidae).

    Science.gov (United States)

    Kuechler, Stefan Martin; Matsuura, Yu; Dettner, Konrad; Kikuchi, Yoshitomo

    2016-06-25

    Diverse phytophagous heteropteran insects, commonly known as stinkbugs, are associated with specific gut symbiotic bacteria, which have been found in midgut cryptic spaces. Recent studies have revealed that members of the stinkbug families Coreidae and Alydidae of the superfamily Coreoidea are consistently associated with a specific group of the betaproteobacterial genus Burkholderia, called the "stinkbug-associated beneficial and environmental (SBE)" group, and horizontally acquire specific symbionts from the environment every generation. However, the symbiotic system of another coreoid family, Stenocephalidae remains undetermined. We herein investigated four species of the stenocephalid genus Dicranocephalus. Examinations via fluorescence in situ hybridization (FISH) and transmission electron microscopy (TEM) revealed the typical arrangement and ultrastructures of midgut crypts and gut symbionts. Cloning and molecular phylogenetic analyses of bacterial genes showed that the midgut crypts of all species are colonized by Burkholderia strains, which were further assigned to different subgroups of the genus Burkholderia. In addition to the SBE-group Burkholderia, a number of stenocephalid symbionts belonged to a novel clade containing B. sordidicola and B. udeis, suggesting a specific symbiont clade for the Stenocephalidae. The symbiotic systems of stenocephalid bugs may provide a unique opportunity to study the ongoing evolution of symbiont associations in the stinkbug-Burkholderia interaction. PMID:27265344

  5. Tasting soil fungal diversity with earth tongues: phylogenetic test of SATe alignments for environmental ITS data.

    Directory of Open Access Journals (Sweden)

    Zheng Wang

    Full Text Available An abundance of novel fungal lineages have been indicated by DNA sequencing of the nuclear ribosomal ITS region from environmental samples such as soil and wood. Although phylogenetic analysis of these novel lineages is a key component of unveiling the structure and diversity of complex communities, such analyses are rare for environmental ITS data due to the difficulties of aligning this locus across significantly divergent taxa. One potential approach to this issue is simultaneous alignment and tree estimation. We targeted divergent ITS sequences of the earth tongue fungi (Geoglossomycetes, a basal class in the Ascomycota, to assess the performance of SATé, recent software that combines progressive alignment and tree building. We found that SATé performed well in generating high-quality alignments and in accurately estimating the phylogeny of earth tongue fungi. Drawing from a data set of 300 sequences of earth tongues and progressively more distant fungal lineages, 30 insufficiently identified ITS sequences from the public sequence databases were assigned to the Geoglossomycetes. The association between earth tongues and plants has been hypothesized for a long time, but hard evidence is yet to be collected. The ITS phylogeny showed that four ectomycorrhizal isolates shared a clade with Geoglossum but not with Trichoglossum earth tongues, pointing to the significant potential inherent to ecological data mining of environmental samples. Environmental sampling holds the key to many focal questions in mycology, and simultaneous alignment and tree estimation, as performed by SATé, can be a highly efficient companion in that pursuit.

  6. Diversity of cytosolic HSP70 Heat Shock Protein from decapods and their phylogenetic placement within Arthropoda.

    Science.gov (United States)

    Baringou, Stephane; Rouault, Jacques-Deric; Koken, Marcel; Hardivillier, Yann; Hurtado, Luis; Leignel, Vincent

    2016-10-10

    The 70kDa heat shock proteins (HSP70) are considered the most conserved members of the HSP family. These proteins are primordial to the cell, because of their implications in many cellular pathways (e. g., development, immunity) and also because they minimize the effects of multiple stresses (e. g., temperature, pollutants, salinity, radiations). In the cytosol, two ubiquitous HSP70s with either a constitutive (HSC70) or an inducible (HSP70) expression pattern are found in all metazoan species, encoded by 5 or 6 genes (Drosophila melanogaster or yeast and human respectively). The cytosolic HSP70 protein family is considered a major actor in environmental adaptation, and widely used in ecology as an important biomarker of environmental stress. Nevertheless, the diversity of cytosolic HSP70 remains unclear amongst the Athropoda phylum, especially within decapods. Using 122 new and 311 available sequences, we carried out analyses of the overall cytosolic HSP70 diversity in arthropods (with a focus on decapods) and inferred molecular phylogenies. Overall structural and phylogenetic analyses showed a surprisingly high diversity in cytosolic HSP70 and revealed the existence of several unrecognised groups. All crustacean HSP70 sequences present signature motifs and molecular weights characteristic of non-organellar HSP70, with multiple specific substitutions in the protein sequence. The cytosolic HSP70 family in arthropods appears to be constituted of at least three distinct groups (annotated as A, B and C), which comprise several subdivisions, including both constitutive and inducible forms. Group A is constituted by several classes of Arthropods, while group B and C seem to be specific to Malacostraca and Hexapoda/Chelicerata, respectively. The HSP70 organization appeared much more complex than previously suggested, and far beyond a simple differentiation according to their expression pattern (HSC70 versus HSP70). This study proposes a new classification of cytosolic

  7. Nitrification of archaeal ammonia oxidizers in a high- temperature hot spring

    Science.gov (United States)

    Chen, Shun; Peng, Xiaotong; Xu, Hengchao; Ta, Kaiwen

    2016-04-01

    The oxidation of ammonia by microbes has been shown to occur in diverse natural environments. However, the link of in situ nitrification activity to taxonomic identities of ammonia oxidizers in high-temperature environments remains poorly understood. Here, we studied in situ ammonia oxidation rates and the diversity of ammonia-oxidizing Archaea (AOA) in surface and bottom sediments at 77 °C in the Gongxiaoshe hot spring, Tengchong, Yunnan, China. The in situ ammonia oxidation rates measured by the 15N-NO3- pool dilution technique in the surface and bottom sediments were 4.80 and 5.30 nmol N g-1 h-1, respectively. Real-time quantitative polymerase chain reaction (qPCR) indicated that the archaeal 16S rRNA genes and amoA genes were present in the range of 0.128 to 1.96 × 108 and 2.75 to 9.80 × 105 gene copies g-1 sediment, respectively, while bacterial amoA was not detected. Phylogenetic analysis of 16S rRNA genes showed high sequence similarity to thermophilic Candidatus Nitrosocaldus yellowstonii, which represented the most abundant operational taxonomic units (OTU) in both surface and bottom sediments. The archaeal predominance was further supported by fluorescence in situ hybridization (FISH) visualization. The cell-specific rate of ammonia oxidation was estimated to range from 0.410 to 0.790 fmol N archaeal cell-1 h-1, higher than those in the two US Great Basin hot springs. These results suggest the importance of archaeal rather than bacterial ammonia oxidation in driving the nitrogen cycle in terrestrial geothermal environments.

  8. Microscopic examination of distribution and phenotypic properties of phylogenetically diverse Chloroflexaceae-related bacteria in hot spring microbial mats

    DEFF Research Database (Denmark)

    Nübel, Ulrich; Bateson, Mary M; Vandieken, Verona;

    2002-01-01

    We investigated the diversity, distribution, and phenotypes of uncultivated Chloroflexaceae-related bacteria in photosynthetic microbial mats of an alkaline hot spring (Mushroom Spring, Yellowstone National Park). By applying a directed PCR approach, molecular cloning, and sequence analysis of 16S...... rRNA genes, an unexpectedly large phylogenetic diversity among these bacteria was detected. Oligonucleotide probes were designed to target 16S rRNAs from organisms affiliated with the genus Chloroflexus or with the type C cluster, a group of previously discovered Chloroflexaceae relatives...

  9. Microscopic Examination of Distribution and Phenotypic Properties of Phylogenetically Diverse Chloroflexaceae-Related Bacteria in Hot Spring Microbial Mats

    DEFF Research Database (Denmark)

    Nübel, U.; Bateson, Mary M.; Vandieken, V.;

    2002-01-01

    We investigated the diversity, distribution, and phenotypes of uncultivated Chloroflexaceae-related bacteria in photosynthetic microbial mats of an alkaline hot spring (Mushroom Spring, Yellowstone National Park). By applying a directed PCR approach, molecular cloning, and sequence analysis of 16S...... rRNA genes, an unexpectedly large phylogenetic diversity among these bacteria was detected. Oligonucleotide probes were designed to target 16S rRNAs from organisms affiliated with the genus Chloroflexus or with the type C cluster, a group of previously discovered Chloroflexaceae relatives...

  10. Environmental shaping of sponge associated archaeal communities.

    Directory of Open Access Journals (Sweden)

    Aline S Turque

    Full Text Available BACKGROUND: Archaea are ubiquitous symbionts of marine sponges but their ecological roles and the influence of environmental factors on these associations are still poorly understood. METHODOLOGY/PRINCIPAL FINDINGS: We compared the diversity and composition of archaea associated with seawater and with the sponges Hymeniacidon heliophila, Paraleucilla magna and Petromica citrina in two distinct environments: Guanabara Bay, a highly impacted estuary in Rio de Janeiro, Brazil, and the nearby Cagarras Archipelago. For this we used metagenomic analyses of 16S rRNA and ammonia monooxygenase (amoA gene libraries. Hymeniacidon heliophila was more abundant inside the bay, while P. magna was more abundant outside and P. citrina was only recorded at the Cagarras Archipelago. Principal Component Analysis plots (PCA generated using pairwise unweighted UniFrac distances showed that the archaeal community structure of inner bay seawater and sponges was different from that of coastal Cagarras Archipelago. Rarefaction analyses showed that inner bay archaeaoplankton were more diverse than those from the Cagarras Archipelago. Only members of Crenarchaeota were found in sponge libraries, while in seawater both Crenarchaeota and Euryarchaeota were observed. Although most amoA archaeal genes detected in this study seem to be novel, some clones were affiliated to known ammonia oxidizers such as Nitrosopumilus maritimus and Cenarchaeum symbiosum. CONCLUSION/SIGNIFICANCE: The composition and diversity of archaeal communities associated with pollution-tolerant sponge species can change in a range of few kilometers, probably influenced by eutrophication. The presence of archaeal amoA genes in Porifera suggests that Archaea are involved in the nitrogen cycle within the sponge holobiont, possibly increasing its resistance to anthropogenic impacts. The higher diversity of Crenarchaeota in the polluted area suggests that some marine sponges are able to change the composition

  11. Phylogenetic Diversity, Distribution, and Cophylogeny of Giant Bacteria (Epulopiscium) with their Surgeonfish Hosts in the Red Sea

    KAUST Repository

    Miyake, Sou

    2016-03-14

    Epulopiscium is a group of giant bacteria found in high abundance in intestinal tracts of herbivorous surgeonfish. Despite their peculiarly large cell size (can be up to 600 μm), extreme polyploidy (some with over 100,000 genome copies per cell) and viviparity (whereby mother cells produce live offspring), details about their diversity, distribution or their role in the host gut are lacking. Previous studies have highlighted the existence of morphologically distinct Epulopiscium cell types (defined as morphotypes A to J) in some surgeonfish genera, but the corresponding genetic diversity and distribution among other surgeonfishes remain mostly unknown. Therefore, we investigated the phylogenetic diversity of Epulopiscium, distribution and co-occurrence in multiple hosts. Here, we identified eleven new phylogenetic clades, six of which were also morphologically characterized. Three of these novel clades were phylogenetically and morphologically similar to cigar-shaped type A1 cells, found in a wide range of surgeonfishes including Acanthurus nigrofuscus, while three were similar to smaller, rod-shaped type E that has not been phylogenetically classified thus far. Our results also confirmed that biogeography appears to have relatively little influence on Epulopiscium diversity, as clades found in the Great Barrier Reef and Hawaii were also recovered from the Red Sea. Although multiple symbiont clades inhabited a given species of host surgeonfish and multiple host species possessed a given symbiont clade, statistical analysis of host and symbiont phylogenies indicated significant cophylogeny, which in turn suggests co-evolutionary relationships. A cluster analysis of Epulopiscium sequences from previously published amplicon sequencing dataset revealed a similar pattern, where specific clades were consistently found in high abundance amongst closely related surgeonfishes. Differences in abundance may indicate specialization of clades to certain gut environments

  12. Diversity of Archaea and detection of crenarchaeotal amoA genes in the rivers Rhine and Têt

    NARCIS (Netherlands)

    Herfort, L.; Kim, J.H.; Coolen, M.J.L.; Abbas, B.; Schouten, S.; Herndl, G.J.; Sinninghe Damste, J.S.

    2009-01-01

    Pelagic archaeal phylogenetic diversity and the potential for crenarchaeotal nitrification of Group 1.1a were determined in the rivers Rhine and Têt by 16S rRNA sequencing, catalyzed reported deposition-fluorescence in situ hybridization (CARD–FISH) and quantification of 16S rRNA and functional gene

  13. Archaeal DNA replication.

    Science.gov (United States)

    Kelman, Lori M; Kelman, Zvi

    2014-01-01

    DNA replication is essential for all life forms. Although the process is fundamentally conserved in the three domains of life, bioinformatic, biochemical, structural, and genetic studies have demonstrated that the process and the proteins involved in archaeal DNA replication are more similar to those in eukaryal DNA replication than in bacterial DNA replication, but have some archaeal-specific features. The archaeal replication system, however, is not monolithic, and there are some differences in the replication process between different species. In this review, the current knowledge of the mechanisms governing DNA replication in Archaea is summarized. The general features of the replication process as well as some of the differences are discussed. PMID:25421597

  14. Phylogenetic diversity of dominant bacterial communities during bioremediation of crude oil-polluted soil

    Directory of Open Access Journals (Sweden)

    Eugene Thomas Cloete

    2011-08-01

    Full Text Available Bioremediation of hydrocarbon pollutants is advantageous owing to the cost-effectiveness of the technology and the ubiquity of hydrocarbon degrading microorganisms in the soil. Soil microbial diversity is affected by hydrocarbon perturbation thus selective enrichment of hydrocarbon utilizers occurs. Hydrocarbons interact with the soil matrix and soil microorganisms determining the fate of the contaminants relative to their chemical nature and microbial degradative capabilities respectively. Bacterial dynamics in crude oil-polluted soil microcosms undergoing bioremediation were investigated over a 42-day period. Four out of the five microcosms containing 4kg of pristine soil each were contaminated with 4% Arabian light crude oil. Three microcosms were amended with either 25g of NPK fertilizer, calcium ammonium nitrate or poultry droppings respectively while the fourth designated oil-contaminated control was unamended. The fifth microcosm had only pristine soil and was set up to ascertain indigenous bacterial community structure pre-contamination. Biostimulated soils were periodically tilled and watered. Hydrocarbon degradation was measured throughout the experimental period by gas chromatography. Gas chromatographic tracing of residual hydrocarbons in biostimulated soils showed marked attenuation of contaminants starting from the second (day 14 till the sixth (day 42 week after contamination whereas no significant reduction in hydrocarbon peaks was seen in the oil contaminated control soil throughout the 6-week experimental period. Molecular fingerprints of bacterial communities involved in aerobic biodegradation of crude oil hydrocarbons in biostimulated soils and controls were generated with DGGE using PCR-amplification of 16S rRNA gene obtained from extracted total soil community DNA. DGGE fingerprints demonstrated that NPK, calcium ammonium nitrate and poultry droppings selected different bacterial populations during the active phase of oil

  15. Genetic Diversity and Phylogenetic Evolution of Tibetan Sheep Based on mtDNA D-Loop Sequences.

    Directory of Open Access Journals (Sweden)

    Jianbin Liu

    Full Text Available The molecular and population genetic evidence of the phylogenetic status of the Tibetan sheep (Ovis aries is not well understood, and little is known about this species' genetic diversity. This knowledge gap is partly due to the difficulty of sample collection. This is the first work to address this question. Here, the genetic diversity and phylogenetic relationship of 636 individual Tibetan sheep from fifteen populations were assessed using 642 complete sequences of the mitochondrial DNA D-loop. Samples were collected from the Qinghai-Tibetan Plateau area in China, and reference data were obtained from the six reference breed sequences available in GenBank. The length of the sequences varied considerably, between 1031 and 1259 bp. The haplotype diversity and nucleotide diversity were 0.992±0.010 and 0.019±0.001, respectively. The average number of nucleotide differences was 19.635. The mean nucleotide composition of the 350 haplotypes was 32.961% A, 29.708% T, 22.892% C, 14.439% G, 62.669% A+T, and 37.331% G+C. Phylogenetic analysis showed that all four previously defined haplogroups (A, B, C, and D were found in the 636 individuals of the fifteen Tibetan sheep populations but that only the D haplogroup was found in Linzhou sheep. Further, the clustering analysis divided the fifteen Tibetan sheep populations into at least two clusters. The estimation of the demographic parameters from the mismatch analyses showed that haplogroups A, B, and C had at least one demographic expansion in Tibetan sheep. These results contribute to the knowledge of Tibetan sheep populations and will help inform future conservation programs about the Tibetan sheep native to the Qinghai-Tibetan Plateau.

  16. Genetic Diversity and Phylogenetic Evolution of Tibetan Sheep Based on mtDNA D-Loop Sequences.

    Science.gov (United States)

    Liu, Jianbin; Ding, Xuezhi; Zeng, Yufeng; Yue, Yaojing; Guo, Xian; Guo, Tingting; Chu, Min; Wang, Fan; Han, Jilong; Feng, Ruilin; Sun, Xiaoping; Niu, Chune; Yang, Bohui; Guo, Jian; Yuan, Chao

    2016-01-01

    The molecular and population genetic evidence of the phylogenetic status of the Tibetan sheep (Ovis aries) is not well understood, and little is known about this species' genetic diversity. This knowledge gap is partly due to the difficulty of sample collection. This is the first work to address this question. Here, the genetic diversity and phylogenetic relationship of 636 individual Tibetan sheep from fifteen populations were assessed using 642 complete sequences of the mitochondrial DNA D-loop. Samples were collected from the Qinghai-Tibetan Plateau area in China, and reference data were obtained from the six reference breed sequences available in GenBank. The length of the sequences varied considerably, between 1031 and 1259 bp. The haplotype diversity and nucleotide diversity were 0.992±0.010 and 0.019±0.001, respectively. The average number of nucleotide differences was 19.635. The mean nucleotide composition of the 350 haplotypes was 32.961% A, 29.708% T, 22.892% C, 14.439% G, 62.669% A+T, and 37.331% G+C. Phylogenetic analysis showed that all four previously defined haplogroups (A, B, C, and D) were found in the 636 individuals of the fifteen Tibetan sheep populations but that only the D haplogroup was found in Linzhou sheep. Further, the clustering analysis divided the fifteen Tibetan sheep populations into at least two clusters. The estimation of the demographic parameters from the mismatch analyses showed that haplogroups A, B, and C had at least one demographic expansion in Tibetan sheep. These results contribute to the knowledge of Tibetan sheep populations and will help inform future conservation programs about the Tibetan sheep native to the Qinghai-Tibetan Plateau. PMID:27463976

  17. Genetic Diversity and Phylogenetic Evolution of Tibetan Sheep Based on mtDNA D-Loop Sequences

    Science.gov (United States)

    Yue, Yaojing; Guo, Xian; Guo, Tingting; Chu, Min; Wang, Fan; Han, Jilong; Feng, Ruilin; Sun, Xiaoping; Niu, Chune; Yang, Bohui; Guo, Jian; Yuan, Chao

    2016-01-01

    The molecular and population genetic evidence of the phylogenetic status of the Tibetan sheep (Ovis aries) is not well understood, and little is known about this species’ genetic diversity. This knowledge gap is partly due to the difficulty of sample collection. This is the first work to address this question. Here, the genetic diversity and phylogenetic relationship of 636 individual Tibetan sheep from fifteen populations were assessed using 642 complete sequences of the mitochondrial DNA D-loop. Samples were collected from the Qinghai-Tibetan Plateau area in China, and reference data were obtained from the six reference breed sequences available in GenBank. The length of the sequences varied considerably, between 1031 and 1259 bp. The haplotype diversity and nucleotide diversity were 0.992±0.010 and 0.019±0.001, respectively. The average number of nucleotide differences was 19.635. The mean nucleotide composition of the 350 haplotypes was 32.961% A, 29.708% T, 22.892% C, 14.439% G, 62.669% A+T, and 37.331% G+C. Phylogenetic analysis showed that all four previously defined haplogroups (A, B, C, and D) were found in the 636 individuals of the fifteen Tibetan sheep populations but that only the D haplogroup was found in Linzhou sheep. Further, the clustering analysis divided the fifteen Tibetan sheep populations into at least two clusters. The estimation of the demographic parameters from the mismatch analyses showed that haplogroups A, B, and C had at least one demographic expansion in Tibetan sheep. These results contribute to the knowledge of Tibetan sheep populations and will help inform future conservation programs about the Tibetan sheep native to the Qinghai-Tibetan Plateau. PMID:27463976

  18. Bacterial and archaeal community structures in the Arctic deep-sea sediment

    Institute of Scientific and Technical Information of China (English)

    LI Yan; LIU Qun; LI Chaolun; DONG Yi; ZHANG Wenyan; ZHANG Wuchang; XIAO Tian

    2015-01-01

    Microbial community structures in the Arctic deep-sea sedimentary ecosystem are determined by organic matter input, energy availability, and other environmental factors. However, global warming and earlier ice-cover melting are affecting the microbial diversity. To characterize the Arctic deep-sea sediment microbial diversity and its rela-tionship with environmental factors, we applied Roche 454 sequencing of 16S rDNA amplicons from Arctic deep-sea sediment sample. Both bacterial and archaeal communities’ richness, compositions and structures as well as tax-onomic and phylogenetic affiliations of identified clades were characterized. Phylotypes relating to sulfur reduction and chemoorganotrophic lifestyle are major groups in the bacterial groups;while the archaeal community is domi-nated by phylotypes most closely related to the ammonia-oxidizing Thaumarchaeota (96.66%) and methanogenic Euryarchaeota (3.21%). This study describes the microbial diversity in the Arctic deep marine sediment (>3 500 m) near the North Pole and would lay foundation for future functional analysis on microbial metabolic processes and pathways predictions in similar environments.

  19. Archaeal diversity in deep-sea hydrothermal sediments from the East Pacific Rise%东太平洋海隆深海热液区沉积物古菌多样性分析

    Institute of Scientific and Technical Information of China (English)

    刘青; 谢运标; 陈逍遥; 周梅先

    2014-01-01

    Archaeal diversity of deep-sea hydrothermal sediments from 3 sites on the East Pacific Rise was investiga-ted and analyzed with polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP).Phyloge-netic analyses revealed that a total of 296 random 16S rRNA gene clones were assigned to Thaumarchaeota (47.64%),Euryarchaeota (44.93%),Crenarchaeota (6.77%)and unclassified Archaea (0.68%).Among them,the genus Nitrosopumilus belonging to the phylum Thaumarchaeota and the class Thermoplasmata belonging to the phylum Euryarchaeota were the dominant groups,representing 35.47% and 27.03% of archaeal clones,re-spectively.In addition,some archaeal 16S rRNA gene sequences were affiliated with deep-sea hydrothermal vent Euryarchaeota 3,5 and 6 (DHVE3,DHVE5 and DHVE6),and Marine Benthic Group B and G (MBGB and MB-GE ).Archaeal communities in sediments from 3 sites on East Pacific Rise were clearly distinct from each other.97 archaeal clones from S5-TVG1 site were divided to Thaumarchaeota (49.48%),Euryarchaeota (49.48%)and Crenarchaeota (1.03%).103 archaeal clones from S14-TVG10 site belonged to Thaumarchaeota(84.47%)and Euryarchaeota (15.53%).96 archaeal clones from S16-TVG12 site were assigned to Euryarchaeota(71.88%), Crenarchaeota (19.79%),Thaumarchaeota (6.25%)and unclassified Archaea (2.08%).Our results indicate that Archaea is abundant and there are a lot of novel archaeal groups in deep-sea hydrothermal sediments from 3 sites on the East Pacific Rise,and the distinct community structure and diversity of Archaea in deep-sea hydrother-mal sediments suggested that the sampling area was influenced by hydrothermalism.%采用PCR-RFLP方法对东太平洋海隆深海热液区3个站位沉积物中的古菌多样性进行了初步研究.结果显示,从古菌16S rRNA基因文库中随机挑取的296个阳性克隆分属奇古菌门(Thaumar-chaeota,47.64%)、广古菌门(Euryarchaeota,44.93%)、泉古菌门(Crenarchaeota,6.77

  20. Niche specialization of terrestrial archaeal ammonia oxidizers

    OpenAIRE

    Gubry-Rangin, Cécile; Hai, Brigitte; Quince, Christopher; Engel, Marion; Thomson, Bruce C.; James, Phillip; Schloter, Michael; Robert I. Griffiths; Prosser, James I.; Nicol, Graeme W.

    2011-01-01

    Soil pH is a major determinant of microbial ecosystem processes and potentially a major driver of evolution, adaptation, and diversity of ammonia oxidizers, which control soil nitrification. Archaea are major components of soil microbial communities and contribute significantly to ammonia oxidation in some soils. To determine whether pH drives evolutionary adaptation and community structure of soil archaeal ammonia oxidizers, sequences of amoA, a key functional gene of ammonia oxidation, were...

  1. Phylogenetic diversity of archaeal 16S rRNA and ammonia monooxygenase genes from tropical estuarine sediments on the central west coast of India

    Digital Repository Service at National Institute of Oceanography (India)

    Singh, S.K.; Verma, P.; Ramaiah, N.; Anil, A.C.; Shouche, Y.S.

    -oxidizing archaea and bacteria in the San Francisco Bay estuary. Environ. Microbiol. 10, 3002-3016. 22. Nasnolkar, C.M., Shirodkar, P.V., Singbal, S.Y.S., 1996. Studies on organic carbon, nitrogen and phosphorous in the sediments of Mandovi Estuary, Goa. Indian J...

  2. Patterns of taxonomic, phylogenetic diversity during a long-term succession of forest on the Loess Plateau, China: insights into assembly process.

    Science.gov (United States)

    Chai, Yongfu; Yue, Ming; Liu, Xiao; Guo, Yaoxin; Wang, Mao; Xu, Jinshi; Zhang, Chenguang; Chen, Yu; Zhang, Lixia; Zhang, Ruichang

    2016-01-01

    Quantifying the drivers underlying the distribution of biodiversity during succession is a critical issue in ecology and conservation, and also can provide insights into the mechanisms of community assembly. Ninety plots were established in the Loess Plateau region of northern Shaanxi in China. The taxonomic and phylogenetic (alpha and beta) diversity were quantified within six succession stages. Null models were used to test whether phylogenetic distance observed differed from random expectations. Taxonomic beta diversity did not show a regular pattern, while phylogenetic beta diversity decreased throughout succession. The shrub stage occurred as a transition from phylogenetic overdispersion to clustering either for NRI (Net Relatedness Index) or betaNRI. The betaNTI (Nearest Taxon Index) values for early stages were on average phylogenetically random, but for the betaNRI analyses, these stages were phylogenetically overdispersed. Assembly of woody plants differed from that of herbaceous plants during late community succession. We suggest that deterministic and stochastic processes respectively play a role in different aspects of community phylogenetic structure for early succession stage, and that community composition of late succession stage is governed by a deterministic process. In conclusion, the long-lasting evolutionary imprints on the present-day composition of communities arrayed along the succession gradient. PMID:27272407

  3. Exploring the determinants of phylogenetic diversity and assemblage structure in conifers across temporal, spatial, and taxonomic scales

    DEFF Research Database (Denmark)

    Eiserhardt, Wolf L.; Borchsenius, Finn; Sandel, Brody Steven;

    have long-lasting effects on species pools and local assemblages. Integrating such long-term dynamics with short-term ecological processes in a common analytical framework is a major challenge of integrative biodiversity science. Phylogenetically informed diversity measures and palaeo-environmental......Composition, diversity, structure and function of modern plant communities are strongly related to the current environment, but they may also depend on past eco-evolutionary dynamics. For example, climate change can exert a strong influence on lineage diversification and niche evolution, and thus...... throughout the natural range of the group (269 TDWG3 “botanical countries”) to infer the effects of current and past climate . To explore the effects of taxonomic and spatial scale, we deconstruct the overall pattern into families and perform a fine-scale analysis for one particular lineage (the genus Pinus...

  4. A proteomic approach to discover and compare interacting partners of papillomavirus E2 proteins from diverse phylogenetic groups.

    Science.gov (United States)

    Jang, Moon Kyoo; Anderson, D Eric; van Doorslaer, Koenraad; McBride, Alison A

    2015-06-01

    Papillomaviruses are a very successful group of viruses that replicate persistently in localized regions of the stratified epithelium of their specific host. Infection results in pathologies ranging from asymptomatic infection, benign warts, to malignant carcinomas. Despite this diversity, papillomavirus genomes are small (7-8 kbp) and contain at most eight genes. To sustain the complex papillomaviral life cycle, each viral protein has multiple functions and interacts with and manipulates a plethora of cellular proteins. In this study, we use tandem affinity purification and MS to identify host factors that interact with 11 different papillomavirus E2 proteins from diverse phylogenetic groups. The E2 proteins function in viral transcription and replication and correspondingly interact with host proteins involved in transcription, chromatin remodeling and modification, replication, and RNA processing. PMID:25758368

  5. A Large and Phylogenetically Diverse Class of Type 1 Opsins Lacking a Canonical Retinal Binding Site

    OpenAIRE

    Becker, EA; Yao, AI; Seitzer, PM; Kind, T; Wang, T.; Eigenheer, R; Shao, KSY; Yarov-Yarovoy, V; Facciotti, MT

    2016-01-01

    Opsins are photosensitive proteins catalyzing light-dependent processes across the tree of life. For both microbial (type 1) and metazoan (type 2) opsins, photosensing depends upon covalent interaction between a retinal chromophore and a conserved lysine residue. Despite recent discoveries of potential opsin homologs lacking this residue, phylogenetic dispersal and functional significance of these abnormal sequences have not yet been investigated. We report discovery of a large group of putat...

  6. Patterns of species diversity and phylogenetic structure of vascular plants on the Qinghai-Tibetan Plateau

    OpenAIRE

    Yan, Yujing; Yang, Xian; Tang, Zhiyao

    2013-01-01

    Large-scale patterns of species richness and the underlying mechanisms regulating these patterns have long been the central issues in biogeography and macroecology. Phylogenetic community structure is a result of combined effects of contemporary ecological interactions, environmental filtering, and evolutionary history, and it links community ecology with biogeography and trait evolution. The Qinghai-Tibetan Plateau provides a good opportunity to test the influence of contemporary climate on ...

  7. Phylogenetic diversity and community structure of sponge-associated bacteria from mangroves of the Caribbean Sea

    KAUST Repository

    Yang, Jiangke

    2011-02-08

    To gain insight into the species richness and phylogeny of the microbial communities associated with sponges in mangroves, we performed an extensive phylogenetic analysis, based on terminal restriction fragment length polymorphism profiling and 16S ribosomal RNA gene sequences, of the 4 sponge species Aplysina fulva, Haliclona hogarthi, Tedania ignis and Ircinia strobilina as well as of ambient seawater. The sponge-associated bacterial communities contained 13 phyla, including Poribacteria and an unclassified group not found in the ambient seawater community, 98% of which comprised Proteobacteria, Cyanobacteria and Bacteroidetes. Although the sponges themselves were phylogenetically distant and bacterial community variation within the host species was observed, microbial phyla such as Proteobacteria, Acidobacteria, Chloroflexi and the unclassified group were consistently observed as the dominant populations within the communities. The sponge-associated bacterial communities resident in the Caribbean Sea mangroves are phylogenetically similar but significantly distinct from communities found in other biogeographical sites such as the deep-water environments of the Caribbean Sea, the South China Sea and Australia. The interspecific variation within the host species and the distinct biogeographical characteristics that the sponge-associated bacteria exhibited indicate that the acquisition, establishment and formation of functional sponge-associated bacterial communities may initially be the product of both vertical and horizontal transmission, and is then shaped by the internal environment created by the sponge species and certain external environmental factors. © Inter-Research 2011.

  8. Ecological Diversity in South American Mammals: Their Geographical Distribution Shows Variable Associations with Phylogenetic Diversity and Does Not Follow the Latitudinal Richness Gradient.

    Directory of Open Access Journals (Sweden)

    Paula Nilda Fergnani

    Full Text Available The extent to which the latitudinal gradient in species richness may be paralleled by a similar gradient of increasing functional or phylogenetic diversity is a matter of controversy. We evaluated whether taxonomic richness (TR is informative in terms of ecological diversity (ED, an approximation to functional diversity and phylogenetic diversity (AvPD using data on 531 mammal species representing South American old autochthonous (marsupials, xenarthrans, mid-Cenozoic immigrants (hystricognaths, primates and newcomers (carnivorans, artiodactyls. If closely related species are ecologically more similar than distantly related species, AvPD will be a strong predictor of ED; however, lower ED than predicted from AvPD may be due to species retaining most of their ancestral characters, suggesting niche conservatism. This pattern could occur in tropical rainforests for taxa of tropical affinity (old autochthonous and mid-Cenozoic immigrants and in open and arid habitats for newcomers. In contrast, higher ED than expected from AvPD could occur, possibly in association with niche evolution, in arid and open habitats for taxa of tropical affinity and in forested habitats for newcomers. We found that TR was a poor predictor of ED and AvPD. After controlling for TR, there was considerable variability in the extent to which AvPD accounted for ED. Taxa of tropical affinity did not support the prediction of ED deficit within tropical rainforests, rather, they showed a mosaic of regions with an excess of ED interspersed with zones of ED deficit within the tropics; newcomers showed ED deficit in arid and open regions. Some taxa of tropical affinity showed excess of ED in tropical desert areas (hystricognaths or temperate semideserts (xenarthrans; newcomers showed excess of ED at cold-temperate latitudes in the Northern Hemisphere. This result suggests that extreme climatic conditions at both temperate and tropical latitudes may have promoted niche evolution in

  9. Phylogenetic characterization of archaea in saltpan sediments.

    Science.gov (United States)

    Ahmad, Nasier; Johri, Sarojini; Sultan, Phalisteen; Abdin, Malik Z; Qazi, Ghulam N

    2011-06-01

    A study was undertaken to investigate the presence of archaeal diversity in saltpan sediments of Goa, India by 16S rDNA-dependent molecular phylogeny. Small subunit rRNA (16S rDNA) from saltpan sediment metagenome were amplified by polymerase chain reaction (PCR) using primers specific to the domain archaea. 10 unique phylotypes were obtained by PCR based RFLP of 16S rRNA genes using endonuclease Msp 1, which was most suitable to score the genetic diversity. These phylotypes spanned a wide range within the domain archaea including both crenarchaeota and euryarcheaota. None of the retrieved crenarchaeota sequences could be grouped with previously cultured crenarchaeota however; two sequences were related with haloarchaea. Most of the sequences determined were closely related to the sequences that had been previously obtained from metagenome of a variety of marine environments. The phylogenetic study of a site investigated for the first time revealed the presence of low archaeal population but showed yet unclassified species, may specially adapted to the salt pan sediment of Goa. PMID:22654153

  10. Bacterial and archaeal dynamics in phylogeny and function in the North Atlantic deep waters

    Science.gov (United States)

    Herndl, G. J.; Brink, M.; Agogue, H.

    2009-04-01

    The diversity and specific functional aspects linked to the N cycle of the bacterio- and archaeoplankton were investigated in the major deep water masses of the North Atlantic following the main driver of the thermohaline circulation, the North Atlantic Deep Water, from 65°N to 5°S. The phylogenetic composition of Bacteria and Archaea is not only depth-dependent but, specific water masses harbor specific prokaryotic communities. The specific composition of these communities in a particular water mass is maintained even over large distances. The distribution of archaeal and bacterial amoA genes were also determined. Archaeal amoA copy numbers decreased drastically with depth especially in the eastern subtropical Atlantic. This coincides with the lower nutrient concentration of the deep waters in the southern parts of the North Atlantic and the older age of the deep-water masses there. These data demonstrate that the diversity and potential nitrification activity are closely linked to the hydrology and chemical characteristics of the major water masses in the North Atlantic.

  11. Phylogenetic diversity and genotypical complexity of H9N2 influenza A viruses revealed by genomic sequence analysis.

    Directory of Open Access Journals (Sweden)

    Guoying Dong

    Full Text Available H9N2 influenza A viruses have become established worldwide in terrestrial poultry and wild birds, and are occasionally transmitted to mammals including humans and pigs. To comprehensively elucidate the genetic and evolutionary characteristics of H9N2 influenza viruses, we performed a large-scale sequence analysis of 571 viral genomes from the NCBI Influenza Virus Resource Database, representing the spectrum of H9N2 influenza viruses isolated from 1966 to 2009. Our study provides a panoramic framework for better understanding the genesis and evolution of H9N2 influenza viruses, and for describing the history of H9N2 viruses circulating in diverse hosts. Panorama phylogenetic analysis of the eight viral gene segments revealed the complexity and diversity of H9N2 influenza viruses. The 571 H9N2 viral genomes were classified into 74 separate lineages, which had marked host and geographical differences in phylogeny. Panorama genotypical analysis also revealed that H9N2 viruses include at least 98 genotypes, which were further divided according to their HA lineages into seven series (A-G. Phylogenetic analysis of the internal genes showed that H9N2 viruses are closely related to H3, H4, H5, H7, H10, and H14 subtype influenza viruses. Our results indicate that H9N2 viruses have undergone extensive reassortments to generate multiple reassortants and genotypes, suggesting that the continued circulation of multiple genotypical H9N2 viruses throughout the world in diverse hosts has the potential to cause future influenza outbreaks in poultry and epidemics in humans. We propose a nomenclature system for identifying and unifying all lineages and genotypes of H9N2 influenza viruses in order to facilitate international communication on the evolution, ecology and epidemiology of H9N2 influenza viruses.

  12. Phylogenetic diversity of plants alters the effect of species richness on invertebrate herbivory

    OpenAIRE

    Russell Dinnage

    2013-01-01

    Long-standing ecological theory proposes that diverse communities of plants should experience a decrease in herbivory. Yet previous empirical examinations of this hypothesis have revealed that plant species richness increases herbivory in just as many systems as it decreases it. In this study, I ask whether more insight into the role of plant diversity in promoting or suppressing herbivory can be gained by incorporating information about the evolutionary history of species in a community. In ...

  13. Antagonistic interactions and phylogenetic diversity of antimicrobial agents producing marine bacteria in Suez Bay

    Directory of Open Access Journals (Sweden)

    Sahar Wefky Mostafa Hassan

    2015-01-01

    Full Text Available Estimation of the total viable bacterial counts and some physicochemical parameters in different sites selected along the Suez Bay was carried out. The highest bacterial density is positively correlated with pollution strength and is localized at the end of the Suez Bay on the one hand of Suez Gulf. It is also function of pollution strength at different examined sites. Antagonistic interactions among the most dominating twenty-two bacterial isolates were assayed. The marine isolate AB12 isolated from sea water of NIOF station displayed the highest antagonistic activity (42.8%. Antagonistic isolates were assigned to phylogenetically 4 different phena which were identified as Staphylococcus, Micrococcus, Enterococcus and Enterobacter species in addition to 5 single clusters which were identified as Acinetobacter sp. and Pseudomonas sp. The promising strain was identified at the molecular level as Pseudoalteromonas piscicida.

  14. The Effect of Dietary Replacement of Ordinary Rice with Red Yeast Rice on Nutrient Utilization, Enteric Methane Emission and Rumen Archaeal Diversity in Goats

    Science.gov (United States)

    Wang, L. Z.; Zhou, M. L.; Wang, J. W.; Wu, D.; Yan, T.

    2016-01-01

    Twenty castrated Boer crossbred goats were used in the present study with two treatments to examine the effect of dietary replacement of ordinary rice with red yeast rice on nutrient utilization, enteric methane emission and ruminal archaea structure and composition. Two treatment diets contained (DM basis) 70.0% of forage, 21.8% of concentrates and 8.2% of either ordinary rice (control) or red yeast rice (RYR). Nutrient utilization was measured and enteric methane emissions were determined in respiration chambers. Results showed that RYR had significantly lower digestibility of N and organic matter compared to control group. However, feeding red yeast rice did not affect N retention as g/d or a proportion of N intake, and reduced heat production as MJ/d or as a proportion of metabolizable energy intake, thus leading to a higher proportion of metabolizable energy intake to be retained in body tissue. RYR also had significantly lower methane emissions either as g/d, or as a proportion of feed intake. Although feeding red yeast rice had no negative effect on any rumen fermentation variables, it decreased serum contents of total cholesterol, triglycerides, HDL-cholesterol and LDL-cholesterol. In the present study, 75616 archaeal sequences were generated and clustered into 2364 Operational Taxonomic Units. At the genus level, the predominant archaea in the rumen of goats was Methanobrevibacter, which was significantly inhibited with the supplementation of red yeast rice. In conclusion, red yeast rice is a potential feed ingredient for mitigation of enteric methane emissions of goats. However, caution should be taken when it is used because it may inhibit the digestibility of some nutrients. Further studies are required to evaluate its potential with different diets and animal species, as well as its effects on animal health and food safety. PMID:27467559

  15. Phylogenetic diversity of carbohydrate degrading culturable bacteria from Mandovi and Zuari estuaries, Goa, west coast of India

    Science.gov (United States)

    Khandeparker, Rakhee; Verma, Preeti; Meena, Ram M.; Deobagkar, Deepti D.

    2011-12-01

    Coastal and estuarine waters are highly productive and dynamic ecosystems. The complex carbohydrate composition of the ecosystem would lead to colonisation of microbial communities with abilities to produce an array of complex carbohydrate degrading enzymes. We have examined the abundance and phylogenetic diversity of culturable bacteria with abilities to produce complex carbohydrate degrading enzymes in the Mondovi and Zuari eustauri. It was interesting to note that 65% of isolated bacteria could produce complex carbohydrate degrading enzymes. A majority of these bacteria belonged to Bacillus genera followed by Vibrio, Marinobacter, Exiquinobacterium, Alteromonas, Enterobacter and Aeromonas. Most abundant bacterial genus to degrade hemicellulose and cellulose were Bacillus and Vibrio respectively. Most abundant bacterial genus to degrade hemicellulose and cellulose were Bacillus and Vibrio respectively. It was seen that 46% of Bacillus had ability to degrade both the substrate while only 14% of Vibrio had bifunctionality.

  16. Phylogenetic Diversity of Ammopiptanthus Rhizobia and Distribution of Rhizobia Associated with Ammopiptanthus mongolicus in Diverse Regions of Northwest China.

    Science.gov (United States)

    Zhao, Liang; Wang, Xinye; Huo, Haibo; Yuan, Guiji; Sun, Yali; Zhang, Dehui; Cao, Ying; Xu, Lin; Wei, Gehong

    2016-07-01

    Aiming to investigate the diversity and distribution of rhizobia associated with Ammopiptanthus, an endangered evergreen legume widely distributed in deserts, we characterized a total of 219 nodule isolates from nine sampling sites in Northwest China with different soil characteristics based upon restriction fragment length polymorphism (RFLP) analysis of 16S ribosomal RNA (rRNA) and symbiotic genes (nodC and nifH). Ten isolates representing different 16S rRNA-RFLP types were selected for further sequence analyses of 16S rRNA and four housekeeping genes. As results, nine genospecies belonging to the genera Ensifer, Neorhizobium, Agrobacterium, Pararhizobium, and Rhizobium could be defined among the isolates. The nodC and nifH phylogenies of 14 isolates representing different symbiotic-RFLP types revealed five lineages linked to Ensifer fredii, Ensifer meliloti, Rhizobium leguminosarum, Mesorhizobium amorphae, and Rhizobium gallicum, which demonstrated the various origins and lateral transfers of symbiotic genes between different genera and species. The rhizobial diversities of Ammopiptanthus mongolicus varied among regions, and the community compositions of rhizobia associated with A. mongolicus were significantly different in wild and cultured fields. Constrained correspondence analysis showed that the distribution of A. mongolicus rhizobia could be explained by available potassium content and that the assembly of symbiotic types was mainly affected by available phosphorus content and carbon-nitrogen ratio. PMID:27079453

  17. Phylogenetic Diversity of Diazotrophs along an Experimental Nutrient Gradient in Mangrove Sediments

    Directory of Open Access Journals (Sweden)

    Isabel C. Romero

    2015-07-01

    Full Text Available The diversity of diazotrophs was studied in the sediment of mangrove forests (Twin Cays, Belize subjected to a long-term fertilization with nitrogen and phosphorus. Terminal Restriction Fragment Length Polymorphism (TRFLP and cloning of PCR-amplified nifH genes were combined via in silico analysis to assign clones to TRFLP-nifH phylotypes, as well as to characterize the occurrence of phylotypes in response to environmental conditions. Results indicated that mangrove sediments from Belize harbor a unique diazotrophic community with a low metabolic diversity dominated by sulfate reducers. The variability of potential nitrogen-fixing sulfate reducers was explained by several environmental parameters, primarily by the abundance of dead roots in the sediments, and the concentration of H2S in the pore-waters. This study describes the complexity of microbial communities within the mangrove sediments with specific functional groups varying along environmental gradients.

  18. Common biosynthetic origins for polycyclic tetramate macrolactams from phylogenetically diverse bacteria

    OpenAIRE

    Blodgett, Joshua A. V.; Oh, Dong-Chan; Cao, Shugeng; Currie, Cameron R.; Kolter, Roberto; Clardy, Jon

    2010-01-01

    A combination of small molecule chemistry, biosynthetic analysis, and genome mining has revealed the unexpected conservation of polycyclic tetramate macrolactam biosynthetic loci in diverse bacteria. Initially our chemical analysis of a Streptomyces strain associated with the southern pine beetle led to the discovery of frontalamides A and B, two previously undescribed members of this antibiotic family. Genome analyses and genetic manipulation of the producing organism led to the identificati...

  19. Hidden diversity and evolutionary trends in malacosporean parasites (Cnidaria: Myxozoa) identified using molecular phylogenetics

    Czech Academy of Sciences Publication Activity Database

    Bartošová, Pavla; Hrabcová, M.; Pecková, Hana; Patra, Sneha; Kodádková, Alena; Jurajda, Pavel; Tyml, Tomáš; Holzer, Astrid S.

    2014-01-01

    Roč. 44, č. 8 (2014), s. 565-577. ISSN 0020-7519 R&D Projects: GA ČR(CZ) GPP506/11/P724; GA ČR GBP505/12/G112; GA AV ČR(CZ) M200961205 Institutional support: RVO:60077344 ; RVO:68081766 Keywords : Buddenbrockia * Tetracapsuloides * diversity * phylogeny * Bryozoa * fish * cryptic * worm Subject RIV: EB - Genetics ; Molecular Biology; EG - Zoology (UBO-W) Impact factor: 3.872, year: 2014

  20. Characterization and Phylogenetic Diversity of Carboxymethyl Cellulase Producing Bacillus Species from a Landfill Ecosystem

    OpenAIRE

    Korpole, Suresh; Sharma, Rashmi; Verma, Dipti

    2011-01-01

    Total population of cellulose degrading bacteria was studied in a landfill ecosystem as a part of microbial diversity study. Samples were obtained from 3 and 5 feet depth of a local landfill being operated for past 10 years. Among many isolates, 22 bacterial strains were selected based on their capability to decompose carboxymethyl cellulose (CMC). These isolates were cultivated on agar medium with CMC as the carbon source. All isolates were Gram positive, endospore forming and alkalophilic b...

  1. Biosynthesis of archaeal membrane ether lipids.

    Science.gov (United States)

    Jain, Samta; Caforio, Antonella; Driessen, Arnold J M

    2014-01-01

    A vital function of the cell membrane in all living organism is to maintain the membrane permeability barrier and fluidity. The composition of the phospholipid bilayer is distinct in archaea when compared to bacteria and eukarya. In archaea, isoprenoid hydrocarbon side chains are linked via an ether bond to the sn-glycerol-1-phosphate backbone. In bacteria and eukarya on the other hand, fatty acid side chains are linked via an ester bond to the sn-glycerol-3-phosphate backbone. The polar head groups are globally shared in the three domains of life. The unique membrane lipids of archaea have been implicated not only in the survival and adaptation of the organisms to extreme environments but also to form the basis of the membrane composition of the last universal common ancestor (LUCA). In nature, a diverse range of archaeal lipids is found, the most common are the diether (or archaeol) and the tetraether (or caldarchaeol) lipids that form a monolayer. Variations in chain length, cyclization and other modifications lead to diversification of these lipids. The biosynthesis of these lipids is not yet well understood however progress in the last decade has led to a comprehensive understanding of the biosynthesis of archaeol. This review describes the current knowledge of the biosynthetic pathway of archaeal ether lipids; insights on the stability and robustness of archaeal lipid membranes; and evolutionary aspects of the lipid divide and the LUCA. It examines recent advances made in the field of pathway reconstruction in bacteria. PMID:25505460

  2. Functionally stable and phylogenetically diverse microbial enrichments from microbial fuel cells during wastewater treatment.

    Science.gov (United States)

    Ishii, Shun'ichi; Suzuki, Shino; Norden-Krichmar, Trina M; Nealson, Kenneth H; Sekiguchi, Yuji; Gorby, Yuri A; Bretschger, Orianna

    2012-01-01

    Microbial fuel cells (MFCs) are devices that exploit microorganisms as biocatalysts to recover energy from organic matter in the form of electricity. One of the goals of MFC research is to develop the technology for cost-effective wastewater treatment. However, before practical MFC applications are implemented it is important to gain fundamental knowledge about long-term system performance, reproducibility, and the formation and maintenance of functionally-stable microbial communities. Here we report findings from a MFC operated for over 300 days using only primary clarifier effluent collected from a municipal wastewater treatment plant as the microbial resource and substrate. The system was operated in a repeat-batch mode, where the reactor solution was replaced once every two weeks with new primary effluent that consisted of different microbial and chemical compositions with every batch exchange. The turbidity of the primary clarifier effluent solution notably decreased, and 97% of biological oxygen demand (BOD) was removed after an 8-13 day residence time for each batch cycle. On average, the limiting current density was 1000 mA/m(2), the maximum power density was 13 mW/m(2), and coulombic efficiency was 25%. Interestingly, the electrochemical performance and BOD removal rates were very reproducible throughout MFC operation regardless of the sample variability associated with each wastewater exchange. While MFC performance was very reproducible, the phylogenetic analyses of anode-associated electricity-generating biofilms showed that the microbial populations temporally fluctuated and maintained a high biodiversity throughout the year-long experiment. These results suggest that MFC communities are both self-selecting and self-optimizing, thereby able to develop and maintain functional stability regardless of fluctuations in carbon source(s) and regular introduction of microbial competitors. These results contribute significantly toward the practical application

  3. Functionally stable and phylogenetically diverse microbial enrichments from microbial fuel cells during wastewater treatment.

    Directory of Open Access Journals (Sweden)

    Shun'ichi Ishii

    Full Text Available Microbial fuel cells (MFCs are devices that exploit microorganisms as biocatalysts to recover energy from organic matter in the form of electricity. One of the goals of MFC research is to develop the technology for cost-effective wastewater treatment. However, before practical MFC applications are implemented it is important to gain fundamental knowledge about long-term system performance, reproducibility, and the formation and maintenance of functionally-stable microbial communities. Here we report findings from a MFC operated for over 300 days using only primary clarifier effluent collected from a municipal wastewater treatment plant as the microbial resource and substrate. The system was operated in a repeat-batch mode, where the reactor solution was replaced once every two weeks with new primary effluent that consisted of different microbial and chemical compositions with every batch exchange. The turbidity of the primary clarifier effluent solution notably decreased, and 97% of biological oxygen demand (BOD was removed after an 8-13 day residence time for each batch cycle. On average, the limiting current density was 1000 mA/m(2, the maximum power density was 13 mW/m(2, and coulombic efficiency was 25%. Interestingly, the electrochemical performance and BOD removal rates were very reproducible throughout MFC operation regardless of the sample variability associated with each wastewater exchange. While MFC performance was very reproducible, the phylogenetic analyses of anode-associated electricity-generating biofilms showed that the microbial populations temporally fluctuated and maintained a high biodiversity throughout the year-long experiment. These results suggest that MFC communities are both self-selecting and self-optimizing, thereby able to develop and maintain functional stability regardless of fluctuations in carbon source(s and regular introduction of microbial competitors. These results contribute significantly toward the

  4. Phylogenetic Diversity and Biological Activity of Actinobacteria Isolated from the Chukchi Shelf Marine Sediments in the Arctic Ocean

    Directory of Open Access Journals (Sweden)

    Meng Yuan

    2014-03-01

    Full Text Available Marine environments are a rich source of Actinobacteria and have the potential to produce a wide variety of biologically active secondary metabolites. In this study, we used four selective isolation media to culture Actinobacteria from the sediments collected from the Chukchi Shelf in the Arctic Ocean. A total of 73 actinobacterial strains were isolated. Based on repetitive DNA fingerprinting analysis, we selected 30 representatives for partial characterization according to their phylogenetic diversity, antimicrobial activities and secondary-metabolite biosynthesis genes. Results from the 16S rRNA gene sequence analysis indicated that the 30 strains could be sorted into 18 phylotypes belonging to 14 different genera: Agrococcus, Arsenicicoccus, Arthrobacter, Brevibacterium, Citricoccus, Janibacter, Kocuria, Microbacterium, Microlunatus, Nocardioides, Nocardiopsis, Saccharopolyspora, Salinibacterium and Streptomyces. To our knowledge, this paper is the first report on the isolation of Microlunatus genus members from marine habitats. Of the 30 isolates, 11 strains exhibited antibacterial and/or antifungal activity, seven of which have activities against Bacillus subtilis and Candida albicans. All 30 strains have at least two biosynthetic genes, one-third of which possess more than four biosynthetic genes. This study demonstrates the significant diversity of Actinobacteria in the Chukchi Shelf sediment and their potential for producing biologically active compounds and novel material for genetic manipulation or combinatorial biosynthesis.

  5. Phylogenetic diversity and biological activity of actinobacteria isolated from the Chukchi Shelf marine sediments in the Arctic Ocean.

    Science.gov (United States)

    Yuan, Meng; Yu, Yong; Li, Hui-Rong; Dong, Ning; Zhang, Xiao-Hua

    2014-03-01

    Marine environments are a rich source of Actinobacteria and have the potential to produce a wide variety of biologically active secondary metabolites. In this study, we used four selective isolation media to culture Actinobacteria from the sediments collected from the Chukchi Shelf in the Arctic Ocean. A total of 73 actinobacterial strains were isolated. Based on repetitive DNA fingerprinting analysis, we selected 30 representatives for partial characterization according to their phylogenetic diversity, antimicrobial activities and secondary-metabolite biosynthesis genes. Results from the 16S rRNA gene sequence analysis indicated that the 30 strains could be sorted into 18 phylotypes belonging to 14 different genera: Agrococcus, Arsenicicoccus, Arthrobacter, Brevibacterium, Citricoccus, Janibacter, Kocuria, Microbacterium, Microlunatus, Nocardioides, Nocardiopsis, Saccharopolyspora, Salinibacterium and Streptomyces. To our knowledge, this paper is the first report on the isolation of Microlunatus genus members from marine habitats. Of the 30 isolates, 11 strains exhibited antibacterial and/or antifungal activity, seven of which have activities against Bacillus subtilis and Candida albicans. All 30 strains have at least two biosynthetic genes, one-third of which possess more than four biosynthetic genes. This study demonstrates the significant diversity of Actinobacteria in the Chukchi Shelf sediment and their potential for producing biologically active compounds and novel material for genetic manipulation or combinatorial biosynthesis. PMID:24663116

  6. Diversity and phylogenetic analyses of bacteria from a shallow-waterhydrothermal vent in Milos island (Greece

    Directory of Open Access Journals (Sweden)

    Donato eGiovannelli

    2013-07-01

    Full Text Available Studies of shallow-water hydrothermal vents have been lagging behind their deep-sea counterparts. Hence, the importance of these systems and their contribution to the local and regional diversity and biogeochemistry is unclear. This study analyzes the bacterial community along a transect at the shallow-water hydrothermal vent system of Milos island, Greece. The abundance and biomass of the prokaryotic community is comparable to areas not affected by hydrothermal activity and was, on average, 1.34×108 cells g-1. The abundance, biomass and diversity of the prokaryotic community increased with the distance from the center of the vent and appeared to be controlled by the temperature gradient rather than the trophic conditions. The retrieved 16S rRNA gene fragments matched sequences from a variety of geothermal environments, although the average similarity was low (94 %, revealing previously undiscovered taxa. Epsilonproteobacteria constituted the majority of the population along the transect, with an average contribution to the total diversity of 60%. The larger cluster of 16S rRNA gene sequences was related to chemolithoautotrophic Sulfurovum spp., an Epsilonproteobacterium so far detected only at deep-sea hydrothermal vents. The presence of previously unknown lineages of Epsilonproteobacteria could be related to the abundance of organic matter in these systems, which may support alternative metabolic strategies to chemolithoautotrophy. The relative contribution of Gammaproteobacteria to the Milos microbial community increased along the transect as the distance from the center of the vent increased. Further attempts to isolate key species from these ecosystems will be critical to shed light on their evolution and ecology.

  7. Phylogenetic and genetic diversity analysis in Leptospira species based on the sequence homology pattern of 16S rRNA gene

    OpenAIRE

    Pasupuleti Sreenivasa Rao

    2013-01-01

    Leptospirosis is a bacterial zoonosis, caused by pathogenic spirochete which belongs to the genus Leptospira. It exists in diverse ecological habitats and affects almost all the mammals including humans. Several online databases like NCBI etc will provide the complete genomic sequence data of various Leptospira species. However, the Phylogenetic and genetic diversity Analysis in Leptospira species based on 16S rRNA gene has not studied in detail. Therefore the present study was conducted. Seq...

  8. The Cladistic Basis for the Phylogenetic Diversity (PD Measure Links Evolutionary Features to Environmental Gradients and Supports Broad Applications of Microbial Ecology’s “Phylogenetic Beta Diversity” Framework

    Directory of Open Access Journals (Sweden)

    Rob Knight

    2009-11-01

    Full Text Available The PD measure of phylogenetic diversity interprets branch lengths cladistically to make inferences about feature diversity. PD calculations extend conventional specieslevel ecological indices to the features level. The “phylogenetic beta diversity” framework developed by microbial ecologists calculates PD-dissimilarities between community localities. Interpretation of these PD-dissimilarities at the feature level explains the framework’s success in producing ordinations revealing environmental gradients. An example gradients space using PD-dissimilarities illustrates how evolutionary features form unimodal response patterns to gradients. This features model supports new application of existing species-level methods that are robust to unimodal responses, plus novel applications relating to climate change, commercial products discovery, and community assembly.

  9. Phylogenetic diversity of fungal communities in areas accessible and not accessible to tourists in Naracoorte Caves.

    Science.gov (United States)

    Adetutu, Eric M; Thorpe, Krystal; Bourne, Steven; Cao, Xiangsheng; Shahsavari, Esmaeil; Kirby, Greg; Ball, Andrew S

    2011-01-01

    The fungal diversity in areas accessible and not accessible to tourists at UNESCO World Heritage-listed Naracoorte Caves was investigated with culture-dependent and culture-independent techniques for assistance in cave management protocol development. The caves were selected based on tourist numbers and configurations: Stick Tomato (open, high numbers), Alexandra (lockable openings, high numbers) and Strawhaven (control; no access). Culture-based survey revealed Ascomycota dominance irrespective of sampling area with Microascales (Trichurus sp.) being most frequently isolated. Some Hypocreales-like sequences belonging to Fusarium sp., Trichoderma sp. and Neonectria sp. (Stick Tomato) were cultured only from areas not accessible to tourists. These orders also were detected by DGGE assay irrespective of sampling area. The predominance of Ascomycota (especially Microascales) suggested their important ecological roles in these caves. Culture-independent analysis showed higher Shannon fungal diversity values (from ITS-based DGGE profiles) in tourist-accessible areas of these caves than in inaccessible areas with the fungal community banding patterns being substantially different in Stick Tomato Cave. Further investigations are needed to determine the cause of the differences in the fungal communities of Stick Tomato Cave, although cave-related factors such as use, configuration and sediment heterogeneity might have contributed to these differences. PMID:21642344

  10. Comparative Analysis of Glycoside Hydrolases Activities from Phylogenetically Diverse Marine Bacteria of the Genus Arenibacter

    Directory of Open Access Journals (Sweden)

    Valery Mikhailov

    2013-06-01

    Full Text Available A total of 16 marine strains belonging to the genus Arenibacter, recovered from diverse microbial communities associated with various marine habitats and collected from different locations, were evaluated in degradation of natural polysaccharides and chromogenic glycosides. Most strains were affiliated with five recognized species, and some presented three new species within the genus Arenibacter. No strains contained enzymes depolymerizing polysaccharides, but synthesized a wide spectrum of glycosidases. Highly active β-N-acetylglucosaminidases and α-N-acetylgalactosaminidases were the main glycosidases for all Arenibacter. The genes, encoding two new members of glycoside hydrolyses (GH families, 20 and 109, were isolated and characterized from the genomes of Arenibacter latericius. Molecular genetic analysis using glycosidase-specific primers shows the absence of GH27 and GH36 genes. A sequence comparison with functionally-characterized GH20 and GH109 enzymes shows that both sequences are closest to the enzymes of chitinolytic bacteria Vibrio furnissii and Cellulomonas fimi of marine and terrestrial origin, as well as human pathogen Elisabethkingia meningoseptica and simbionts Akkermansia muciniphila, gut and non-gut Bacteroides, respectively. These results revealed that the genus Arenibacter is a highly taxonomic diverse group of microorganisms, which can participate in degradation of natural polymers in marine environments depending on their niche and habitat adaptations. They are new prospective candidates for biotechnological applications due to their production of unique glycosidases.

  11. Archaeal CRISPR-based immune systems

    DEFF Research Database (Denmark)

    Garrett, Roger A; Vestergaard, Gisle Alberg; Shah, Shiraz Ali

    2011-01-01

    CRISPR (clustered regularly interspaced short palindromic repeats)-based immune systems are essentially modular with three primary functions: the excision and integration of new spacers, the processing of CRISPR transcripts to yield mature CRISPR RNAs (crRNAs), and the targeting and cleavage of...... foreign nucleic acid. The primary target appears to be the DNA of foreign genetic elements, but the CRISPR/Cmr system that is widespread amongst archaea also specifically targets and cleaves RNA in vitro. The archaeal CRISPR systems tend to be both diverse and complex. Here we examine evidence for...... CRISPR loci and the evidence for intergenomic exchange of CRISPR systems....

  12. Novel viral genomes identified from six metagenomes reveal wide distribution of archaeal viruses and high viral diversity in terrestrial hot springs

    DEFF Research Database (Denmark)

    Islin, Sóley Ruth; Menzel, Peter; Krogh, Anders;

    2016-01-01

    number of unique contigs and the lack of a completely assembled genome for this family. This is further supported by the large number of novel genes in the complete and partial genomes showing no sequence similarities to public databases. CRISPR analysis revealed hundreds of novel CRISPR loci and...... thousands of novel CRISPR spacers from each metagenome, reinforcing the notion of high viral diversity in the thermal environment....

  13. Phylogenetic and genetic diversity analysis in Leptospira species based on the sequence homology pattern of 16S rRNA gene

    Directory of Open Access Journals (Sweden)

    Pasupuleti Sreenivasa Rao

    2013-08-01

    Full Text Available Leptospirosis is a bacterial zoonosis, caused by pathogenic spirochete which belongs to the genus Leptospira. It exists in diverse ecological habitats and affects almost all the mammals including humans. Several online databases like NCBI etc will provide the complete genomic sequence data of various Leptospira species. However, the Phylogenetic and genetic diversity Analysis in Leptospira species based on 16S rRNA gene has not studied in detail. Therefore the present study was conducted. Sequences of various species related to genus Leptospira obtained from the NCBI database etc and aligned (CLUSTAL_X. Two Phylogenetic trees were constructed (MEGA-5 in which the first one is related to various serovars of L. interrogans and the other is related to various species of Leptospira. The Phylogenetic trees revealed the relationship and genetic diversity of various serovars of L. interrogans and the other Leptospira species, with their nearest phylogenetic relatives. In the first tree, two major clades were observed which were named as A and B, whereas in the second tree, three major clades were observed and named as A, B and C respectively. Aquifex pyrophilus strain has been used for out grouping in both the trees. The genetic distance between the species in the phylogenetic tree is presented by a bar which represents 0.5 nucleotide substitutions per alignment position in the 16S rRNA gene sequence among the various serovars of L. interrogans while 0.05 nucleotide substitutions in case of various species related to the genus Leptospira. Thus, the findings from the above study confirm that the genus Leptospira exhibits genetic diversity in the 16S rRNA gene. [Int J Res Med Sci 2013; 1(4.000: 369-377

  14. Phylogenetic diversity of alkaline protease-producing psychrotrophic bacteria from glacier and cold environments of Lahaul and Spiti, India.

    Science.gov (United States)

    Salwan, Richa; Gulati, Arvind; Kasana, Ramesh Chand

    2010-04-01

    The diversity of proteolytic bacteria associated with a glacier and cold environment soils from three different locations in Lahaul and Spiti, India was investigated. Two hundred seventeen bacterial strains were isolated in pure culture. Subsequently these strains were screened for protease-production and one hundred nine showed protease production. From these protease producing psychrotrophic bacteria twenty showing high enzyme production at low temperature and alkaline pH were characterized and identified. The 16S rRNA phylogenetic analysis revealed that none of the strains showed 100% identity with the validly published species of various genera. Isolates belonged to three classes i.e. Actinobacteria, Gammaproteobacteria and Alphaproteobacteria, and were affiliated with the genera Acinetobacter, Arthrobacter, Mycoplana, Pseudomonas, Pseudoxanthomonas, Serratia and Stenotrophomonas. The optimal growth temperature ranged from 10 to 28 degrees C and interestingly, high levels of enzyme productions were measured at growth temperatures between 15 and 25 degrees C, for most of the isolates in plate assay. Most of the isolates were found to produce at least two other hydrolytic enzymes along with protease. The crude protease from one strain was active over broad range of temperature and pH with optima at 30 degrees C and 7.5, respectively. The protease activity was enhanced by Ca(2+), dithiothreitol and beta-mercaptoethanol. While Na(+), Hg(2+), Zn(2+), Mn(2+), phenylmethanesulfonyl fluoride and ethylenediaminetetraacetic acid did not showed much effect on protease activity. The results enrich our knowledge on the psychrotrophic bacterial diversity and biogeographic distribution of enzyme producing bacteria in western Himalaya. PMID:20082368

  15. Conservation actions based on red lists do not capture the functional and phylogenetic diversity of birds in Brazil.

    Directory of Open Access Journals (Sweden)

    José Hidasi-Neto

    Full Text Available Red Lists of threatened species play a critical role in conservation science and practice. However, policy-making based on Red Lists ignores ecological and evolutionary consequences of losing biodiversity because these lists focus on species alone. To decide if relying on Red Lists alone can help to conserve communities' functional (FD and phylogenetic (PD diversity, it is useful to evaluate whether Red List categories represent species with diverse ecological traits and evolutionary histories. Additionally, local scale analyses using regional Red Lists should represent more realistic pools of co-occurring species and thereby better capture eventual losses of FD and PD. Here, we used 21 life-history traits and a phylogeny for all Brazilian birds to determine whether species assigned under the IUCN global Red List, the Brazilian national, and regional Red Lists capture more FD and PD than expected by chance. We also built local Red Lists and analysed if they capture more FD and PD at the local scale. Further, we investigated whether individual threat categories have species with greater FD and PD than expected by chance. At any given scale, threat categories did not capture greater FD or PD than expected by chance. Indeed, mostly categories captured equal or less FD or PD than expected by chance. These findings would not have great consequences if Red Lists were not often considered as a major decision support tool for policy-making. Our results challenge the practice of investing conservation resources based only on species Red Lists because, from an ecological and evolutionary point of view, this would be the same as protecting similar or random sets of species. Thus, new prioritization methods, such as the EDGE of Existence initiative, should be developed and applied to conserve species' ecological traits and evolutionary histories at different spatial scales.

  16. Comparison of Archaeal and Bacterial Diversity in Methane Seep Carbonate Nodules and Host Sediments, Eel River Basin and Hydrate Ridge, USA.

    Science.gov (United States)

    Mason, Olivia U; Case, David H; Naehr, Thomas H; Lee, Raymond W; Thomas, Randal B; Bailey, Jake V; Orphan, Victoria J

    2015-10-01

    Anaerobic oxidation of methane (AOM) impacts carbon cycling by acting as a methane sink and by sequestering inorganic carbon via AOM-induced carbonate precipitation. These precipitates commonly take the form of carbonate nodules that form within methane seep sediments. The timing and sequence of nodule formation within methane seep sediments are not well understood. Further, the microbial diversity associated with sediment-hosted nodules has not been well characterized and the degree to which nodules reflect the microbial assemblage in surrounding sediments is unknown. Here, we conducted a comparative study of microbial assemblages in methane-derived authigenic carbonate nodules and their host sediments using molecular, mineralogical, and geochemical methods. Analysis of 16S rRNA gene diversity from paired carbonate nodules and sediments revealed that both sample types contained methanotrophic archaea (ANME-1 and ANME-2) and syntrophic sulfate-reducing bacteria (Desulfobacteraceae and Desulfobulbaceae), as well as other microbial community members. The combination of geochemical and molecular data from Eel River Basin and Hydrate Ridge suggested that some nodules formed in situ and captured the local sediment-hosted microbial community, while other nodules may have been translocated or may represent a record of conditions prior to the contemporary environment. Taken together, this comparative analysis offers clues to the formation regimes and mechanisms of sediment-hosted carbonate nodules. PMID:25947096

  17. Phylogenetic congruence and ecological coherence in terrestrial Thaumarchaeota.

    Science.gov (United States)

    Oton, Eduard Vico; Quince, Christopher; Nicol, Graeme W; Prosser, James I; Gubry-Rangin, Cécile

    2016-01-01

    Thaumarchaeota form a ubiquitously distributed archaeal phylum, comprising both the ammonia-oxidising archaea (AOA) and other archaeal groups in which ammonia oxidation has not been demonstrated (including Group 1.1c and Group 1.3). The ecology of AOA in terrestrial environments has been extensively studied using either a functional gene, encoding ammonia monooxygenase subunit A (amoA) or 16S ribosomal RNA (rRNA) genes, which show phylogenetic coherence with respect to soil pH. To test phylogenetic congruence between these two markers and to determine ecological coherence in all Thaumarchaeota, we performed high-throughput sequencing of 16S rRNA and amoA genes in 46 UK soils presenting 29 available contextual soil characteristics. Adaptation to pH and organic matter content reflected strong ecological coherence at various levels of taxonomic resolution for Thaumarchaeota (AOA and non-AOA), whereas nitrogen, total mineralisable nitrogen and zinc concentration were also important factors associated with AOA thaumarchaeotal community distribution. Other significant associations with environmental factors were also detected for amoA and 16S rRNA genes, reflecting different diversity characteristics between these two markers. Nonetheless, there was significant statistical congruence between the markers at fine phylogenetic resolution, supporting the hypothesis of low horizontal gene transfer between Thaumarchaeota. Group 1.1c Thaumarchaeota were also widely distributed, with two clusters predominating, particularly in environments with higher moisture content and organic matter, whereas a similar ecological pattern was observed for Group 1.3 Thaumarchaeota. The ecological and phylogenetic congruence identified is fundamental to understand better the life strategies, evolutionary history and ecosystem function of the Thaumarchaeota. PMID:26140533

  18. Phylogenetics and genetic diversity of the Cotesia flavipes complex of parasitoid wasps (Hymenoptera: Braconidae), biological control agents of lepidopteran stemborers.

    Science.gov (United States)

    Muirhead, Kate A; Murphy, Nicholas P; Sallam, Nader; Donnellan, Stephen C; Austin, Andrew D

    2012-06-01

    The Cotesia flavipes complex of parasitoid wasps (Hymenoptera: Braconidae) are economically important for the biological control of lepidopteran stemboring pests associated with gramineous crops. Some members of the complex successfully parasitize numerous stemborer pest species, however certain geographic populations have demonstrated variation in the range of hosts that they parasitize. In addition, the morphology of the complex is highly conserved and considerable confusion surrounds the identity of species and host-associated biotypes. We generated nucleotide sequence data for two mtDNA genes (COI, 16S) and three anonymous nuclear loci (CfBN, CfCN, CfEN) for the C. flavipes complex. To analyze genetic variation and relationships among populations we used (1) concatenated mtDNA and nDNA data, (2) a nDNA multilocus network approach, and (3) two species tree inference methods, i.e. Bayesian estimation of species trees (BEST) and Bayesian inference of species trees from multilocus data with (*)BEAST. All phylogenetic analyses provide strong support for monophyly of the complex and the presence of at least four species, C. chilonis (from China and Japan), C. sesamiae (from Africa), C. flavipes (originating from the Indo-Asia region but introduced into Africa and the New World), and C. nonagriae (from Australia and Papua New Guinea). Haplotype diversity of geographic populations relates to historical biogeographic barriers and biological control introductions, and reflects previous reports of ecological variation in these species. Strong discordance was found between the mitochondrial and nuclear markers in the Papua New Guinea haplotypes, which may be an outcome of hybridization and introgression of C. flavipes and C. nonagriae. The position of Cotesia flavipes from Japan was not well supported in any analysis and was the sister taxon to C. nonagriae (mtDNA, (*)BEAST), C. flavipes (nDNA) or C. flavipes+C. nonagriae (BEST) and, may represent a cryptic species. The

  19. Comprehensive Phylogenetic Analysis Sheds Light on the Diversity and Origin of the MLO Family of Integral Membrane Proteins.

    Science.gov (United States)

    Kusch, Stefan; Pesch, Lina; Panstruga, Ralph

    2016-01-01

    Mildew resistanceLocusO(MLO) proteins are polytopic integral membrane proteins that have long been considered as plant-specific and being primarily involved in plant-powdery mildew interactions. However, research in the past decade has revealed that MLO proteins diverged into a family with several clades whose members are associated with different physiological processes. We provide a largely increased dataset of MLO amino acid sequences, comprising nearly all major land plant lineages. Based on this comprehensive dataset, we defined seven phylogenetic clades and reconstructed the likely evolution of the MLO family in embryophytes. We further identified several MLO peptide motifs that are either conserved in all MLO proteins or confined to one or several clades, supporting the notion that clade-specific diversification of MLO functions is associated with particular sequence motifs. In baker's yeast, some of these motifs are functionally linked to transmembrane (TM) transport of organic molecules and ions. In addition, we attempted to define the evolutionary origin of the MLO family and found that MLO-like proteins with highly diverse membrane topologies are present in green algae, but also in the distinctly related red algae (Rhodophyta), Amoebozoa, and Chromalveolata. Finally, we discovered several instances of putative fusion events between MLO proteins and different kinds of proteins. Such Rosetta stone-type hybrid proteins might be instructive for future analysis of potential MLO functions. Our findings suggest that MLO is an ancient protein that possibly evolved in unicellular photosynthetic eukaryotes, and consolidated in land plants with a conserved topology, comprising seven TM domains and an intrinsically unstructured C-terminus. PMID:26893454

  20. Diversity of Archaea and detection of crenarchaeotal amoA genes in the rivers Rhine and Têt

    OpenAIRE

    Herfort, L.; Kim, J.H.; M J L Coolen; Abbas, B.; Schouten, S; Herndl, G. J.; Sinninghe Damste, J.S.

    2009-01-01

    Pelagic archaeal phylogenetic diversity and the potential for crenarchaeotal nitrification of Group 1.1a were determined in the rivers Rhine and Têt by 16S rRNA sequencing, catalyzed reported deposition-fluorescence in situ hybridization (CARD–FISH) and quantification of 16S rRNA and functional genes. Euryarchaeota were, for the first time, detected in temperate river water even though a net predominance of crenarchaeotal phylotypes was found. Differences in phylogenic distribution were obser...

  1. Seasonality and resource availability control bacterial and archaeal communities in soils of a temperate beech forest

    OpenAIRE

    Rasche, Frank; Knapp, Daniela; Kaiser, Christina; Koranda, Marianne; Kitzler, Barbara; Zechmeister-Boltenstern, Sophie; Richter, Andreas; Sessitsch, Angela

    2010-01-01

    It was hypothesized that seasonality and resource availability altered through tree girdling were major determinants of the phylogenetic composition of the archaeal and bacterial community in a temperate beech forest soil. During a 2-year field experiment, involving girdling of beech trees to intercept the transfer of easily available carbon (C) from the canopy to roots, members of the dominant phylogenetic microbial phyla residing in top soils under girdled versus untreated control trees wer...

  2. Archaeal rRNA operons, intron splicing and homing endonucleases, RNA polymerase operons and phylogeny

    DEFF Research Database (Denmark)

    Garrett, Roger Antony; Aagaard, Claus Sindbjerg; Andersen, Morten; Dalgaard, Jacob; Lykke-Andersen, Jens; Phan, Hoa T.N.; Trevisanato, Siro; Østergaard, Laust; Larsen, Niels; Leffers, Henrik

    1994-01-01

    Over the past decade our laboratory has had a strong interest in defining the phylogenetic status of the archaea. This has involved determining and analysing the sequences of operons of both rRNAs and RNA polymerases and it led to the discovery of the first archaeal rRNA intron. What follows is a...

  3. Archaeal ammonia oxidizers respond to soil factors at smaller spatial scales than the overall archaeal community does in a high Arctic polar oasis.

    Science.gov (United States)

    Banerjee, Samiran; Kennedy, Nabla; Richardson, Alan E; Egger, Keith N; Siciliano, Steven D

    2016-06-01

    Archaea are ubiquitous and highly abundant in Arctic soils. Because of their oligotrophic nature, archaea play an important role in biogeochemical processes in nutrient-limited Arctic soils. With the existing knowledge of high archaeal abundance and functional potential in Arctic soils, this study employed terminal restriction fragment length polymorphism (t-RFLP) profiling and geostatistical analysis to explore spatial dependency and edaphic determinants of the overall archaeal (ARC) and ammonia-oxidizing archaeal (AOA) communities in a high Arctic polar oasis soil. ARC communities were spatially dependent at the 2-5 m scale (P diversity indices of both ARC and AOA communities showed high spatial dependency along the landscape and resembled scaling of edaphic factors. The spatial link between archaeal community structure and soil resources found in this study has implications for predictive understanding of archaea-driven processes in polar oases. PMID:27045904

  4. Archaeal virus-host interactions

    NARCIS (Netherlands)

    Quax, T.E.F.

    2013-01-01

      The work presented in this thesis provides novel insights in several aspects of the molecular biology of archaea, bacteria and their viruses. Three fundamentally different groups of viruses are associated with the three domains of life. Archaeal viruses are characterized by a particularly

  5. Extraction and phylogenetic survey of extracellular and intracellular DNA in marine sediments

    DEFF Research Database (Denmark)

    Torti, Andrea

    hand, it undermines the assumption of a direct link between the total extracted DNA and the local, currently living microbial assemblages in sediments, in terms of both microbial cell abundance and diversity. Hindered by technical challenges associated with separating eDNA from DNA enclosed in living...... cells (intracellular DNA, iDNA) and from the sediment matrix, full understanding of the qualitative and quantitative contribution of extracellular sequences to the overall phylogenetic diversity in sediments remains to be achieved. In this thesis, a method was devised for separate extraction of eDNA and...... iDNA, and validated for minimal cell lysis during the eDNA extraction process. The optimized method was applied to investigate and compare the bacterial, archaeal, and eukaryotic diversity within iDNA and eDNA pools, in the context of differing geochemical and lithological zones in the Holocene...

  6. Bacterial and archaeal communities in Lake Nyos (Cameroon, Central Africa)

    OpenAIRE

    Tiodjio, Rosine E.; Sakatoku, Akihiro; Nakamura, Akihiro; Tanaka, Daisuke; Fantong, Wilson Y.; Tchakam, Kamtchueng B.; Tanyileke, Gregory; Ohba, Takeshi; Hell, Victor J.; Kusakabe, Minoru; Nakamura, Shogo; Ueda, Akira

    2014-01-01

    The aim of this study was to assess the microbial diversity associated with Lake Nyos, a lake with an unusual chemistry in Cameroon. Water samples were collected during the dry season on March 2013. Bacterial and archaeal communities were profiled using Polymerase Chain Reaction-Denaturing Gradient Gel Electrophoresis (PCR-DGGE) approach of the 16S rRNA gene. The results indicate a stratification of both communities along the water column. Altogether, the physico-chemical data and microbial s...

  7. Diversity of Phylogenetic Information According to the Locus and the Taxonomic Level: An Example from a Parasitic Mesostigmatid Mite Genus

    Directory of Open Access Journals (Sweden)

    Lise Roy

    2010-04-01

    Full Text Available Molecular markers for cladistic analyses may perform differently according to the taxonomic group considered and the historical level under investigation. Here we evaluate the phylogenetic potential of five different markers for resolving evolutionary relationships within the ectoparasitic genus Dermanyssus at the species level, and their ability to address questions about the evolution of specialization. COI provided 9–18% divergence between species (up to 9% within species, 16S rRNA 10–16% (up to 4% within species, ITS1 and 2 2–9% (up to 1% within species and Tropomyosin intron n 8–20% (up to 6% within species. EF-1a revealed different non-orthologous copies withinindividuals of Dermanyssus and Ornithonyssus. Tropomyosin intron n was shown containing consistent phylogenetic signal at the specific level within Dermanyssus and represents a promising marker for future prospects in phylogenetics of Acari. Phylogenetic analyses revealed that the generalist condition is apomorphic and D. gallinae mightrepresent a complex of hybridized lineages. The split into hirsutus-group and gallinae-group in Dermanyssus does not seem to be appropriate based upon these results and D. longipes appears to be composed of two different entities.

  8. Diversity of phylogenetic information according to the locus and the taxonomic level: an example from a parasitic mesostigmatid mite genus.

    Science.gov (United States)

    Roy, Lise; Dowling, Ashley P G; Chauve, Claude Marie; Buronfosse, Thierry

    2010-01-01

    Molecular markers for cladistic analyses may perform differently according to the taxonomic group considered and the historical level under investigation. Here we evaluate the phylogenetic potential of five different markers for resolving evolutionary relationships within the ectoparasitic genus Dermanyssus at the species level, and their ability to address questions about the evolution of specialization. COI provided 9-18% divergence between species (up to 9% within species), 16S rRNA 10-16% (up to 4% within species), ITS1 and 2 2-9% (up to 1% within species) and Tropomyosin intron n 8-20% (up to 6% within species). EF-1alpha revealed different non-orthologous copies within individuals of Dermanyssus and Ornithonyssus. Tropomyosin intron n was shown containing consistent phylogenetic signal at the specific level within Dermanyssus and represents a promising marker for future prospects in phylogenetics of Acari. Phylogenetic analyses revealed that the generalist condition is apomorphic and D. gallinae might represent a complex of hybridized lineages. The split into hirsutus-group and gallinae-group in Dermanyssus does not seem to be appropriate based upon these results and D. longipes appears to be composed of two different entities. PMID:20480038

  9. Thrombin-like enzymes from venom gland of Deinagkistrodon acutus:cDNA cloning, mechanism of diversity and phylogenetic tree construction

    Institute of Scientific and Technical Information of China (English)

    Xiang-dong ZHA; He-sheng HUANG; Li-zhi ZHOU; Jing LIU; Kang-sen XU

    2006-01-01

    Aim: To clone cDNAs of thrombin-like enzymes (TLEs) from venom gland of Deinagkistrodon acutus and analyze the mechanisms by which their structural diversity arose. Methods: Reverse transcription-polymerase chain reaction and gene cloning techniques were used, and the cloned sequences were analyzed by using bioinformatics tools. Results: Novel cDNAs of snake venom TLEs were cloned. The possibilities of post-transcriptional recombination and horizontal gene transfer are discussed. A phylogenetic tree was constructed. Conclusion:The cDNAs of snake venom TLEs exhibit great diversification. There are several types of structural variations. These variations may be attributable to certain mechanisms including recombination.

  10. Phylogenetic relationships between the six superoxide dismutase proteins (FeSOD of Trichomonas vaginalis and FeSOD6 genetic diversity

    Directory of Open Access Journals (Sweden)

    Hwang U.W

    2002-03-01

    Full Text Available The parasitic protozoan Trichomonas vaginalis is known to contain several types of Fe-containing superoxide dismutase proteins (FeSOD. Using three different methods of phylogenetic analysis, maximum parsimony (MP, neighbor joining (NJ, and maximum likelihood (ML methods, we examined the phylogenetic relationships among the six FeSOD (FeSOD1-FeSOD6 based on their amino acid sequences. All the analyses consistently suggested that the six proteins formed a monophyletic group implying that they probably be originated from an ancestral protein form through repeated duplication events. Although MP tree was totally unresolved, the NJ and ML trees revealed that FeSOD6 placed the most basal position and thus emerged earlier than the other five gene types during the evolution of T. vaginalis. Phylogenetic relationships among the five remaining proteins were (FeSOD2, FeSOD3, (FeSOD4, (FeSODl, FeSOD5 although weakly supported in terms of bootstrapping values. In addition to this, we newly designed two PCR primer specifically amplifying full-length FeSOD6 gene and examined its genetic diversity among 1 2 T. vaginalis isolates from five countries and three continents. They had the same nucleotide sequences except those of three Korean isolates which showed one to three different nucleotides

  11. Global analysis of viral infection in an archaeal model system

    Directory of Open Access Journals (Sweden)

    JosephSteffens

    2012-12-01

    Full Text Available The origin and evolutionary relationship of viruses is poorly understood. This makes archaeal virus-host of particular interest because the hosts generally root near the base of phylogenetic trees, while some of the viruses have clear structural similarities to those that infect prokaryotic and eukaryotic cells. Despite the advantageous position for use in evolutionary studies, little is known about archaeal viruses or how they interact with their hosts, compared to viruses of bacteria and eukaryotes. In addition, many archaeal viruses have been isolated from extreme environments and present a unique opportunity for elucidating factors that are important for existence at the extremes.. In this article we focus on virus-host interactions using a proteomics approach to study Sulfolobus Turreted Icosahedral Virus (STIV infection of Sulfolobus solfataricus P2. Using cultures grown from the ATCC cell stock, a single cycle of STIV infection was sampled 6 times over a 72 hr period. More than 700 proteins were identified throughout the course of the experiments. Seventy one host proteins were found to change by nearly two-fold (p<0.05 with 40 becoming more abundant and 31 less abundant. The modulated proteins represent 30 different cell pathways and 14 COG groups. 2D gel analysis showed that changes in post translational modifications were a common feature of the affected proteins. The results from these studies showed that the prokaryotic antiviral adaptive immune system CRISPR associated proteins (CAS proteins were regulated in response to the virus infection. It was found that regulated proteins come from mRNAs with a shorter than average half-life. In addition, activity-based protein profiling (ABPP profiling on 2D gels showed caspase, hydrolase and tyrosine phosphatase enzyme activity labeling at the protein isoform level. Together, this data provides a more detailed global view of archaeal cellular responses to viral infection, demonstrates the

  12. Diversity of Phylogenetic Information According to the Locus and the Taxonomic Level: An Example from a Parasitic Mesostigmatid Mite Genus

    OpenAIRE

    Lise Roy; Dowling, Ashley P.G.; Claude Marie Chauve; Thierry Buronfosse

    2010-01-01

    Molecular markers for cladistic analyses may perform differently according to the taxonomic group considered and the historical level under investigation. Here we evaluate the phylogenetic potential of five different markers for resolving evolutionary relationships within the ectoparasitic genus Dermanyssus at the species level, and their ability to address questions about the evolution of specialization. COI provided 9–18% divergence between species (up to 9% within species), 16S rRNA 10–16%...

  13. Multilocus phylogenetic analyses reveal unexpected abundant diversity and significant disjunct distribution pattern of the Hedgehog Mushrooms (Hydnum L.).

    Science.gov (United States)

    Feng, Bang; Wang, Xiang-Hua; Ratkowsky, David; Gates, Genevieve; Lee, Su See; Grebenc, Tine; Yang, Zhu L

    2016-01-01

    Hydnum is a fungal genus proposed by Linnaeus in the early time of modern taxonomy. It contains several ectomycorrhizal species which are commonly consumed worldwide. However, Hydnum is one of the most understudied fungal genera, especially from a molecular phylogenetic view. In this study, we extensively gathered specimens of Hydnum from Asia, Europe, America and Australasia, and analyzed them by using sequences of four gene fragments (ITS, nrLSU, tef1α and rpb1). Our phylogenetic analyses recognized at least 31 phylogenetic species within Hydnum, 15 of which were reported for the first time. Most Australasian species were recognized as strongly divergent old relics, but recent migration between Australasia and the Northern Hemisphere was also detected. Within the Northern Hemisphere, frequent historical biota exchanges between the Old World and the New World via both the North Atlantic Land Bridge and the Bering Land Bridge could be elucidated. Our study also revealed that most Hydnum species found in subalpine areas of the Hengduan Mountains in southwestern China occur in northeastern/northern China and Europe, indicating that the composition of the mycobiota in the Hengduan Mountains reigion is more complicated than what we have known before. PMID:27151256

  14. Phylogenetic diversity of culturable endophytic fungi in Dongxiang wild rice (Oryza rufipogon Griff), detection of polyketide synthase gene and their antagonistic activity analysis.

    Science.gov (United States)

    Wang, Ya; Gao, Bo Liang; Li, Xi Xi; Zhang, Zhi Bin; Yan, Ri Ming; Yang, Hui Lin; Zhu, Du

    2015-11-01

    The biodiversity of plant endophytic fungi is enormous, numerous competent endophytic fungi are capable of providing different forms of fitness benefits to host plants and also could produce a wide array of bioactive natural products, which make them a largely unexplored source of novel compounds with potential bioactivity. In this study, we provided a first insights into revealing the diversity of culturable endophytic fungi in Dongxiang wild rice (Oryza rufipogon Griff.) from China using rDNA-ITS phylogenetic analysis. Here, the potential of fungi in producing bioactive natural products was estimated based on the beta-ketosynthase detected in the polyketide synthase (PKS) gene cluster and on the bioassay of antagonistic activity against two rice phytopathogens Thanatephorus cucumeris and Xanthomonas oryzae. A total of 229 endophytic fungal strains were validated in 19 genera. Among the 24 representative strains, 13 strains displayedantagonistic activity against the phytopathogens. Furthermore, PKS genes were detected in 9 strains, indicating their potential for synthesising PKS compounds. Our study confirms the phylogenetic diversity of endophytic fungi in O. rufipogon G. and highlights that endophytic fungi are not only promising resources of biocontrol agents against phytopathogens of rice plants, but also of bioactive natural products and defensive secondary metabolites. PMID:26466878

  15. The effects of micro-aeration on the phylogenetic diversity of microorganisms in a thermophilic anaerobic municipal solid-waste digester.

    Science.gov (United States)

    Tang, Yueqin; Shigematsu, Toru; Ikbal; Morimura, Shigeru; Kida, Kenji

    2004-05-01

    We demonstrated previously that micro-aeration allows construction of an effective thermophilic methane-fermentation system for treatment of municipal solid waste (MSW) without production of H(2)S. In the present study, we compared the microbial communities in a thermophilic MSW digester without aeration and with micro-aeration by fluorescence in situ hybridization (FISH), denaturing gradient gel electrophoresis (DGGE), phylogenetic analysis of libraries of 16S rRNA gene clones and quantitative real-time PCR. Moreover, we studied the activity of sulfate-reducing bacteria (SRB) by analysis of the transcription of the gene for dissimilatory sulfite reductase (dsr). Experiments using FISH revealed that microorganisms belonging to the domain Bacteria dominated in the digester both without aeration and with micro-aeration. Phylogenetic analysis based on 16S rRNA gene and analysis of bacteria by DGGE did not reveal any obvious difference within the microbial communities under the two aeration conditions, and bacteria affiliated with the phylum Firmicutes were dominant. In Archaea, the population of Methanosarcina decreased while the population of Methanoculleus increased as a result of micro-aerations as revealed by the analysis of 16S rRNA gene clones and quantitative real-time PCR. Reverse transcription and PCR (RT-PCR) demonstrated the transcription of dsrA not only in the absence of aeration but also in the presence of micro-aeration, even under conditions where no H(2)S was detected in the biogas. In conclusion, micro-aeration has no obvious effects on the phylogenetic diversity of microorganisms. Furthermore, the activity of SRBs in the digester was not repressed even though the concentration of H(2)S in the biogas was very low under the micro-aeration conditions. PMID:15159157

  16. Genetic diversity and phylogenetic analysis of the attachment glycoprotein of phocine distemper viruses of the 2002 and 1988 epizootics

    DEFF Research Database (Denmark)

    Nielsen, L; Arctander, P; Jensen, T H;

    2009-01-01

    To investigate the possible origin and spread of the dramatic re-emergent 2002 distemper epizootic observed among seals in Danish Waters, we have sequenced wild-type genes of the attachment (H) glycoproteins of viruses from both the 2002 and 1988 epizootics. Phylogenetic analysis of the H genes of...... phocine distemper virus (PDV) together with other morbilliviruses, suggests that the re-emergent 2002 PDV is more closely related to a putative recent ancestral PDV than the 1988 PDV isolates. Moreover, upsurges of distemper disease in land-living carnivores linked in time and locality to the 2002 seal...... epizootic in Danish Waters was investigated and determined to be caused by canine distemper virus, the closest relative of PDV, revealing no direct epidemiological link to the seal epizootics. (C) 2009 Elsevier B.V. All rights reserved....

  17. A user's guide to a data base of the diversity of Pseudomonas syringae and its application to classifying strains in this phylogenetic complex.

    Directory of Open Access Journals (Sweden)

    Odile Berge

    Full Text Available The Pseudomonas syringae complex is composed of numerous genetic lineages of strains from both agricultural and environmental habitats including habitats closely linked to the water cycle. The new insights from the discovery of this bacterial species in habitats outside of agricultural contexts per se have led to the revelation of a wide diversity of strains in this complex beyond what was known from agricultural contexts. Here, through Multi Locus Sequence Typing (MLST of 216 strains, we identified 23 clades within 13 phylogroups among which the seven previously described P. syringae phylogroups were included. The phylogeny of the core genome of 29 strains representing nine phylogroups was similar to the phylogeny obtained with MLST thereby confirming the robustness of MLST-phylogroups. We show that phenotypic traits rarely provide a satisfactory means for classification of strains even if some combinations are highly probable in some phylogroups. We demonstrate that the citrate synthase (cts housekeeping gene can accurately predict the phylogenetic affiliation for more than 97% of strains tested. We propose a list of cts sequences to be used as a simple tool for quickly and precisely classifying new strains. Finally, our analysis leads to predictions about the diversity of P. syringae that is yet to be discovered. We present here an expandable framework mainly based on cts genetic analysis into which more diversity can be integrated.

  18. A user's guide to a data base of the diversity of Pseudomonas syringae and its application to classifying strains in this phylogenetic complex.

    Science.gov (United States)

    Berge, Odile; Monteil, Caroline L; Bartoli, Claudia; Chandeysson, Charlotte; Guilbaud, Caroline; Sands, David C; Morris, Cindy E

    2014-01-01

    The Pseudomonas syringae complex is composed of numerous genetic lineages of strains from both agricultural and environmental habitats including habitats closely linked to the water cycle. The new insights from the discovery of this bacterial species in habitats outside of agricultural contexts per se have led to the revelation of a wide diversity of strains in this complex beyond what was known from agricultural contexts. Here, through Multi Locus Sequence Typing (MLST) of 216 strains, we identified 23 clades within 13 phylogroups among which the seven previously described P. syringae phylogroups were included. The phylogeny of the core genome of 29 strains representing nine phylogroups was similar to the phylogeny obtained with MLST thereby confirming the robustness of MLST-phylogroups. We show that phenotypic traits rarely provide a satisfactory means for classification of strains even if some combinations are highly probable in some phylogroups. We demonstrate that the citrate synthase (cts) housekeeping gene can accurately predict the phylogenetic affiliation for more than 97% of strains tested. We propose a list of cts sequences to be used as a simple tool for quickly and precisely classifying new strains. Finally, our analysis leads to predictions about the diversity of P. syringae that is yet to be discovered. We present here an expandable framework mainly based on cts genetic analysis into which more diversity can be integrated. PMID:25184292

  19. A User's Guide to a Data Base of the Diversity of Pseudomonas syringae and Its Application to Classifying Strains in This Phylogenetic Complex

    Science.gov (United States)

    Berge, Odile; Monteil, Caroline L.; Bartoli, Claudia; Chandeysson, Charlotte; Guilbaud, Caroline; Sands, David C.; Morris, Cindy E.

    2014-01-01

    The Pseudomonas syringae complex is composed of numerous genetic lineages of strains from both agricultural and environmental habitats including habitats closely linked to the water cycle. The new insights from the discovery of this bacterial species in habitats outside of agricultural contexts per se have led to the revelation of a wide diversity of strains in this complex beyond what was known from agricultural contexts. Here, through Multi Locus Sequence Typing (MLST) of 216 strains, we identified 23 clades within 13 phylogroups among which the seven previously described P. syringae phylogroups were included. The phylogeny of the core genome of 29 strains representing nine phylogroups was similar to the phylogeny obtained with MLST thereby confirming the robustness of MLST-phylogroups. We show that phenotypic traits rarely provide a satisfactory means for classification of strains even if some combinations are highly probable in some phylogroups. We demonstrate that the citrate synthase (cts) housekeeping gene can accurately predict the phylogenetic affiliation for more than 97% of strains tested. We propose a list of cts sequences to be used as a simple tool for quickly and precisely classifying new strains. Finally, our analysis leads to predictions about the diversity of P. syringae that is yet to be discovered. We present here an expandable framework mainly based on cts genetic analysis into which more diversity can be integrated. PMID:25184292

  20. Modelling the evolution of the archaeal tryptophan synthase

    Directory of Open Access Journals (Sweden)

    Merkl Rainer

    2007-04-01

    Full Text Available Abstract Background Microorganisms and plants are able to produce tryptophan. Enzymes catalysing the last seven steps of tryptophan biosynthesis are encoded in the canonical trp operon. Among the trp genes are most frequently trpA and trpB, which code for the alpha and beta subunit of tryptophan synthase. In several prokaryotic genomes, two variants of trpB (named trpB1 or trpB2 occur in different combinations. The evolutionary history of these trpB genes is under debate. Results In order to study the evolution of trp genes, completely sequenced archaeal and bacterial genomes containing trpB were analysed. Phylogenetic trees indicated that TrpB sequences constitute four distinct groups; their composition is in agreement with the location of respective genes. The first group consisted exclusively of trpB1 genes most of which belonged to trp operons. Groups two to four contained trpB2 genes. The largest group (trpB2_o contained trpB2 genes all located outside of operons. Most of these genes originated from species possessing an operon-based trpB1 in addition. Groups three and four pertain to trpB2 genes of those genomes containing exclusively one or two trpB2 genes, but no trpB1. One group (trpB2_i consisted of trpB2 genes located inside, the other (trpB2_a of trpB2 genes located outside the trp operon. TrpA and TrpB form a heterodimer and cooperate biochemically. In order to characterise trpB variants and stages of TrpA/TrpB cooperation in silico, several approaches were combined. Phylogenetic trees were constructed for all trp genes; their structure was assessed via bootstrapping. Alternative models of trpB evolution were evaluated with parsimony arguments. The four groups of trpB variants were correlated with archaeal speciation. Several stages of TrpA/TrpB cooperation were identified and trpB variants were characterised. Most plausibly, trpB2 represents the predecessor of the modern trpB gene, and trpB1 evolved in an ancestral bacterium

  1. Phylogenetic diversity of bacteria associated with Paleolithic paintings and surrounding rock walls in two Spanish caves (Llonín and La Garma).

    Science.gov (United States)

    Schabereiter-Gurtner, Claudia; Saiz-Jimenez, Cesareo; Piñar, Guadalupe; Lubitz, Werner; Rölleke, Sabine

    2004-02-01

    Bacterial diversity in caves is still rarely investigated using culture-independent techniques. In the present study, bacterial communities on Paleolithic paintings and surrounding rock walls in two Spanish caves (Llonín and La Garma) were analyzed, using 16S rDNA-based denaturing gradient gel electrophoresis community fingerprinting and phylogenetic analyses without prior cultivation. Results revealed complex bacterial communities consisting of a high number of novel 16S rDNA sequence types and indicated a high biodiversity of lithotrophic and heterotrophic bacteria. Identified bacteria were related to already cultured bacteria (39 clones) and to environmental 16S rDNA clones (46 clones). The nearest phylogenetic relatives were members of the Proteobacteria (41.1%), of the Acidobacterium division (16.5%), Actinobacteria (20%), Firmicutes (10.6%), of the Cytophaga/Flexibacter/Bacteroides division (5.9%), Nitrospira group (3.5%), green non-sulfur bacteria (1.2%), and candidate WS3 division (1.2%). Thirteen of these clones were most closely related to those obtained from the previous studies on Tito Bustillo Cave. The comparison of the present data with the data obtained previously from Altamira and Tito Bustillo Caves revealed similarities in the bacterial community components, especially in the high abundance of the Acidobacteria and Rhizobiaceae, and in the presence of bacteria related to ammonia and sulfur oxidizers. PMID:19712338

  2. Phylogenetic diversity and similarity of active sites of Shiga toxin (stx) in Shiga toxin-producing Escherichia coli (STEC) isolates from humans and animals.

    Science.gov (United States)

    Asakura, H; Makino, S; Kobori, H; Watarai, M; Shirahata, T; Ikeda, T; Takeshi, K

    2001-08-01

    Nucleotide sequences of Shiga toxin (Stx) genes in STEC from various origins were determined and characterized by phylogenetic analysis based on Shiga toxin (Stx) with those deposited in GenBank. The phylogenetic trees placed Stx1 and Stx2 into two and five groups respectively, and indicated that Stx1 in sheep-origin STEC were placed into a different group from those in other STEC, and that Stx2 of deer-origin STEC also belonged to the unique group and appeared to be distantly related to human-origin STEC. On the other hand, Stx of STEC isolated from cattle, seagulls and flies were closely related to those of human-origin STEC. Such a diversity of Stx suggested that STEC might be widely disseminated in many animal species, and be dependent on their host species or their habitat. In addition, the active sites in both toxins were compared; the active sites in both subunits of Stx in all the animal-origin STEC were identical to those in human-origin STEC, suggesting that all the toxin of STEC from animals might be also cytotoxic, and therefore, such animal-origin STEC might have potential pathogenicity for humans. PMID:11561972

  3. Phylogenetic diversity and similarity of active sites of Shiga toxin (stx) in Shiga toxin-producing Escherichia coli (STEC) isolates from humans and animals.

    Science.gov (United States)

    Asakura, H.; Makino, S.; Kobori, H.; Watarai, M.; Shirahata, T.; Ikeda, T.; Takeshi, K.

    2001-01-01

    Nucleotide sequences of Shiga toxin (Stx) genes in STEC from various origins were determined and characterized by phylogenetic analysis based on Shiga toxin (Stx) with those deposited in GenBank. The phylogenetic trees placed Stx1 and Stx2 into two and five groups respectively, and indicated that Stx1 in sheep-origin STEC were placed into a different group from those in other STEC, and that Stx2 of deer-origin STEC also belonged to the unique group and appeared to be distantly related to human-origin STEC. On the other hand, Stx of STEC isolated from cattle, seagulls and flies were closely related to those of human-origin STEC. Such a diversity of Stx suggested that STEC might be widely disseminated in many animal species, and be dependent on their host species or their habitat. In addition, the active sites in both toxins were compared; the active sites in both subunits of Stx in all the animal-origin STEC were identical to those in human-origin STEC, suggesting that all the toxin of STEC from animals might be also cytotoxic, and therefore, such animal-origin STEC might have potential pathogenicity for humans. PMID:11561972

  4. Some Like it High! Phylogenetic Diversity of High-Elevation Cyanobacterial Community from Biological Soil Crusts of Western Himalaya

    Czech Academy of Sciences Publication Activity Database

    Čapková, Kateřina; Hauer, Tomáš; Řeháková, Klára; Doležal, Jiří

    2016-01-01

    Roč. 71, č. 1 (2016), s. 113-123. ISSN 0095-3628 R&D Projects: GA ČR GA13-13368S Institutional support: RVO:67985939 Keywords : Soil crusts * Cyanobacterial diversity * Western Himalayas Subject RIV: EH - Ecology, Behaviour Impact factor: 2.973, year: 2014

  5. Some like it high! Phylogenetic diversity of high-elevation cyanobacterial community from biological soil crusts of Western Himalaya.

    Czech Academy of Sciences Publication Activity Database

    Čapková, K.; Hauer, T.; Řeháková, Klára; Doležal, J.

    2016-01-01

    Roč. 71, č. 1 (2016), s. 113-123. ISSN 0095-3628 Institutional support: RVO:60077344 Keywords : soil crusts * cyanobacterial diversity * Western Himalayas * high -elevation * desert * phosphorus Subject RIV: EH - Ecology, Behaviour Impact factor: 2.973, year: 2014

  6. Comparative molecular analysis of the prokaryotic diversity of two salt mine soils in southwest China.

    Science.gov (United States)

    Xiao, Wei; Wang, Zhi-Gang; Wang, Yong-Xia; Schneegurt, Mark A; Li, Zhi-Ying; Lai, Yong-Hong; Zhang, Shi-Ying; Wen, Meng-Liang; Cui, Xiao-Long

    2013-11-01

    While much is known about the microbial diversity in some hypersaline environments, little is known about those of salt mine tunnel soils. The objective of this study was to conduct a comprehensive phylogenetic comparison of the archaeal and bacterial communities present in Yipinglang salt mine (YPL) and Qiaohou salt mine (QH) tunnels differing in salinity and salt composition using 16S rRNA gene clone libraries. Two hundred twenty-eight sequences for QH and 182 sequences for YPL were analyzed by amplified ribosomal DNA-restriction analysis. Libraries revealed 44 bacterial and 57 archaeal different operational taxonomic units belonging to at least 8 bacterial and 3 archaeal divisions, but not all divisions were observed in both salt mines. The bacterial community affiliated with the Bacteroidetes was the most abundant (60% of clones) in QH, while the community in YPL was dominated by δ-Proteobacteria (45% of clones). All archaeal clones from QH were affiliated with Halobacteriaceae. In contrast, in the YPL library, 49% of clones belonged to Halobacteriaceae, 31% of clones related to unclassified archaea, and 21% of clones belonged to Crenarchaeota. Bioinformatic analysis and comparisons showed that the clone libraries were significantly different between two salt mines. PMID:23457089

  7. Phylogenetic Diversity and Antimicrobial Activities of Culturable Endophytic Actinobacteria Isolated from Different Egyptian Marine Sponges and Soft Corals

    OpenAIRE

    El-Bondkly, Ahmed-Mohammed; El-Gendy, Mervat M. A. A.; Wiese, Jutta; Imhoff, Johannes F.

    2012-01-01

    A cultivation-based approach was employed to isolate and compare the endophytic culturable actinobacterial diversity associated with different Egyptian marine sponges and soft corals. A total of 13 culturable actinobacteria isolates were obtained, five of which isolated from different sponges, two (AE27 and AE32) and three (AE29, AE41 and AE46) were isolated from Haliclona sp. and Callyspongia sp. collected from Sharm El-Sheikh and Hurghada, Egypt, respectively. Eight were isolated from diffe...

  8. Phylogenetic Diversity and Environment-Specific Distributions of Glycosyl Hydrolase Family 10 Xylanases in Geographically Distant Soils

    OpenAIRE

    Wang, Guozeng; Meng, Kun; Luo, Huiying; Wang, Yaru; Huang, Huoqing; Shi, Pengjun; Yang, Peilong; Zhang, Zhifang; Yao, Bin

    2012-01-01

    Background Xylan is one of the most abundant biopolymers on Earth. Its degradation is mediated primarily by microbial xylanase in nature. To explore the diversity and distribution patterns of xylanase genes in soils, samples of five soil types with different physicochemical characters were analyzed. Methodology/Principal Findings Partial xylanase genes of glycoside hydrolase (GH) family 10 were recovered following direct DNA extraction from soil, PCR amplification and cloning. Combined with o...

  9. Elevational gradients in phylogenetic structure of ant communities reveal the interplay of biotic and abiotic constraints on diversity

    Czech Academy of Sciences Publication Activity Database

    Machač, A.; Janda, Milan; Dunn, R. R.; Sanders, N. J.

    2011-01-01

    Roč. 34, č. 3 (2011), s. 364-371. ISSN 0906-7590 R&D Projects: GA AV ČR KJB612230701; GA MŠk LC06073; GA ČR GD206/08/H044; GA ČR GA206/09/0115; GA ČR GAP505/10/0673 Institutional research plan: CEZ:AV0Z50070508 Keywords : diversity Subject RIV: EH - Ecology, Behaviour Impact factor: 4.188, year: 2011

  10. High Bacterial Diversity and Phylogenetic Novelty in Dark Euxinic Freshwaters Analyzed by 16S Tag Community Profiling.

    Science.gov (United States)

    Llorens-Marès, Tomàs; Triadó-Margarit, Xavier; Borrego, Carles M; Dupont, Chris L; Casamayor, Emilio O

    2016-04-01

    Microbial communities growing under extreme low redox conditions are present in anoxic and sulfide-rich (euxinic) environments such as karstic lakes and experience limitation of electron acceptors. The fine natural chemical gradients and the large diversity of organic and inorganic compounds accumulated in bottom waters are impossible to mimic under laboratory conditions, and only a few groups have been cultured. We investigated the bacterial composition in the oxic-anoxic interface and in the deep waters of three sulfurous lakes from the Lake Banyoles karstic area (NE Spain) through 16S rRNA gene tag sequencing and identified the closest GenBank counterpart. High diversity indices were found in most of the samples with >15 phyla/classes and >45 bacterial orders. A higher proportion of operational taxonomic units (OTUs) of the "highest novelty" was found in the hypolimnia (38 % of total sequences) than in the metalimnia (17 %), whereas the percentage of OTUs closer to cultured counterparts (i.e., 97 % identity in the 16S rRNA gene) was 6 to 21 %, respectively. Elusimicrobia, Chloroflexi, Fibrobacteres, and Spirochaetes were the taxa with the highest proportion of novel sequences. Interestingly, tag sequencing results comparison with metagenomics data available from the same dataset, showed a systematic underestimation of sulfur-oxidizing Epsilonproteobacteria with the currently available 907R "universal" primer. Overall, despite the limitation of electron acceptors, a highly diverse and novel assemblage was present in dark and euxinic hypolimnetic freshwaters, unveiling a hotspot of microbial diversity with a remarkable gap with cultured counterparts. PMID:26552395

  11. Phylogenetic diversity and antimicrobial activities of bryozoan-associated bacteria isolated from Mediterranean and Baltic Sea habitats.

    Science.gov (United States)

    Heindl, Herwig; Wiese, Jutta; Thiel, Vera; Imhoff, Johannes F

    2010-03-01

    To date, only a small number of investigations covering microbe-bryozoa associations have been carried out. Most of them have focused on a few bryozoan species and none have covered the antibacterial activities of associated bacteria. In the current study, the proportion and phylogenetic classification of Bryozoan-associated bacteria with antimicrobial properties were investigated. Twenty-one specimens of 14 different bryozoan species were collected from several sites in the Baltic and the Mediterranean Sea. A total of 340 associated bacteria were isolated, and 101 displayed antibiotic activities. While antibiosis was predominantly directed against Gram-positive test strains, 16S rRNA gene sequencing revealed affiliation of the isolates to Gram-negative classes (Flavobacteria, Alpha- and Gammaproteobacteria). One isolate was related to the Gram-positive Actinobacteria. The sequences were grouped into 27 phylotypes on the basis of similarity values >or=99.5%. A host-specific affiliation was not revealed as members of the same phylotype were derived from different bryozoan species. Site-specific patterns, however, were demonstrated. Strains of the genera Sphingomonas and Alteromonas were exclusively isolated from Mediterranean sites, whereas Shewanella, Marinomonas and Vibrio-related isolates were only from Baltic sites. Although Pseudoalteromonas affiliated strains were found in both habitats, they were separated into respective phylotypes. Isolates with 16S rDNA similarity values Tenacibaculum. PMID:20153592

  12. Identification and characterization of T-cell antigen receptor-related genes in phylogenetically diverse vertebrate species.

    Science.gov (United States)

    Rast, J P; Haire, R N; Litman, R T; Pross, S; Litman, G W

    1995-01-01

    Characterization of the structure, multiplicity, organization, and cell lineage-specific expression of T-cell receptor (TCR) genes of nonmammalian vertebrate species is central to the understanding of the evolutionary origins of rearranging genes of the vertebrate immune system. We recently described a polymerase chain reaction (PCR) strategy that relies on short sequence similarities shared by nearly all vertebrate TCR and immunoglobulin (Ig) variable (V) regions and have used this approach to isolate a TCR beta (TCRB) homolog from a cartilaginous fish. Using these short PCR products as probes in spleen cDNA and genomic libraries, we were able to isolate a variety of unique TCR and TCR-like genes. Here we report the identification and characterization of a chicken TCR gamma (TCRG) homolog, apparent Xenopus and pufferfish TCR alpha (TCRA) homologs, and two horned shark TCR delta (TCRD)-like genes. In addition, we have identified what could be a novel representative of the Ig gene superfamily in the pufferfish. This method of using short, minimally degenerate PCR primers should speed progress in the phylogenetic investigations of the TCR and related genes and lend important insights into both the origins and functions of these unique gene systems. PMID:7642232

  13. Midichloria mitochondrii is widespread in hard ticks (Ixodidae) and resides in the mitochondria of phylogenetically diverse species.

    Science.gov (United States)

    Epis, S; Sassera, D; Beninati, T; Lo, N; Beati, L; Piesman, J; Rinaldi, L; McCoy, K D; Torina, A; Sacchi, L; Clementi, E; Genchi, M; Magnino, S; Bandi, C

    2008-04-01

    The hard tick Ixodes ricinus (Ixodidae) is the sole animal thus far shown to harbour an intra-mitochondrial bacterium, which has recently been named Midichloria mitochondrii. The objectives of this work were (i) to screen ixodid ticks for Midichloria-related bacteria and (ii) to determine whether these bacteria exploit the intra-mitochondrial niche in other tick species. Our main goal was to discover further models of this peculiar form of symbiosis. We have thus performed a PCR screening for Midichloria-related bacteria in samples of ixodid ticks collected in Italy, North America and Iceland. A total of 7 newly examined species from 5 genera were found positive for bacteria closely related to M. mitochondrii. Samples of the tick species Rhipicephalus bursa, found positive in the PCR screening, were analysed with transmission electron microscopy, which revealed the presence of bacteria both in the cytoplasm and in the mitochondria of the oocytes. There is thus evidence that bacteria invade mitochondria in at least 2 tick species. Phylogenetic analysis on the bacterial 16S rRNA gene sequences generated from positive specimens revealed that the bacteria form a monophyletic group within the order Rickettsiales. The phylogeny of Midichloria symbionts and related bacteria does not appear completely congruent with the phylogeny of the hosts. PMID:18205982

  14. Phylogenetic analysis reveals positive correlations between adaptations to diverse hosts in a group of pathogen-like herbivores.

    Science.gov (United States)

    Peterson, Daniel A; Hardy, Nate B; Morse, Geoffrey E; Stocks, Ian C; Okusu, Akiko; Normark, Benjamin B

    2015-10-01

    A jack of all trades can be master of none-this intuitive idea underlies most theoretical models of host-use evolution in plant-feeding insects, yet empirical support for trade-offs in performance on distinct host plants is weak. Trade-offs may influence the long-term evolution of host use while being difficult to detect in extant populations, but host-use evolution may also be driven by adaptations for generalism. Here we used host-use data from insect collection records to parameterize a phylogenetic model of host-use evolution in armored scale insects, a large family of plant-feeding insects with a simple, pathogen-like life history. We found that a model incorporating positive correlations between evolutionary changes in host performance best fit the observed patterns of diaspidid presence and absence on nearly all focal host taxa, suggesting that adaptations to particular hosts also enhance performance on other hosts. In contrast to the widely invoked trade-off model, we advocate a "toolbox" model of host-use evolution in which armored scale insects accumulate a set of independent genetic tools, each of which is under selection for a single function but may be useful on multiple hosts. PMID:26374400

  15. Dark matter in archaeal genomes: a rich source of novel mobile elements, defense systems and secretory complexes

    OpenAIRE

    Makarova, Kira S.; Wolf, Yuri I; Forterre, Patrick; Prangishvili, David; Krupovic, Mart; Koonin, Eugene V

    2014-01-01

    Microbial genomes encompass a sizable fraction of poorly characterized, narrowly spread fast-evolving genes. Using sensitive methods for sequences comparison and protein structure prediction, we performed a detailed comparative analysis of clusters of such genes, which we denote “dark matter islands”, in archaeal genomes. The dark matter islands comprise up to 20 % of archaeal genomes and show remarkable heterogeneity and diversity. Nevertheless, three classes of entities are common in these ...

  16. The Genetic Diversity and Phylogenetic Characteritics of Rotavirus VP4(P Genotypes in Children With Acute Diarrhea

    Directory of Open Access Journals (Sweden)

    Haghshenas Z

    2011-11-01

    Full Text Available Background: Acute gastroenteritis is a major cause of morbidity and mortality among children in developing countries. Rotaviruses are recognized as the most common etiologic factors of gastroenteritis. In this study, we determined the epidemiologic features, clinical symptoms and molecular structure of rotavirus VP4(P genotypes in children with acute diarrhea in Bahrami Hospital in Tehran Iran, during 2009 for justifying the routine use of rotavirus vaccines in children. Methods: One hundred fifty fecal samples from 150 children with acute diarrhea in Bahrami Pediatric Hospital in Tehran, Iran were collected from January to December 2009. The patients’ mean age was 20.90+18.19 years (ranging from 1 month to 14 years. Fecal samples were transported on ice to the laboratory of virology department of Pasture Institute of Iran. The demographic and clinical data for each case were entered in an author-devised questionnaire. Group A rotavirus was detected by dsRNA-PAGE. Subsequently, rotavirus genotyping (VP4 was performed by semi-nested multiple RT-PCR and the phylogenetic tree of the Rotavirus nucleotides was constructed. The data were analyzed by statistical tests including Wilcoxon signed and Mann-Whitney U. Results: Rotavirus was isolated in 19.3% of the samples, more than 90% of which had long RNA patterns. The predominant genotype (VP4 was P[8] (86% and other genotypes respectively were P[6] (6.9% and P[4] (6.9%. Conclusion: A high prevalence of the P[8] genotype was found to be the cause of acute diarrhea. The analysis of P[8] genotype sequence showed a high level of similarity of the virus in this study with those of other Asian countries.

  17. Phylogenetic analysis of methanogens from the bovine rumen

    Directory of Open Access Journals (Sweden)

    Forster Robert J

    2001-05-01

    Full Text Available Abstract Background Interest in methanogens from ruminants has resulted from the role of methane in global warming and from the fact that cattle typically lose 6 % of ingested energy as methane. Several species of methanogens have been isolated from ruminants. However they are difficult to culture, few have been consistently found in high numbers, and it is likely that major species of rumen methanogens are yet to be identified. Results Total DNA from clarified bovine rumen fluid was amplified using primers specific for Archaeal 16S rRNA gene sequences (rDNA. Phylogenetic analysis of 41 rDNA sequences identified three clusters of methanogens. The largest cluster contained two distinct subclusters with rDNA sequences similar to Methanobrevibacter ruminantium 16S rDNA. A second cluster contained sequences related to 16S rDNA from Methanosphaera stadtmanae, an organism not previously described in the rumen. The third cluster contained rDNA sequences that may form a novel group of rumen methanogens. Conclusions The current set of 16S rRNA hybridization probes targeting methanogenic Archaea does not cover the phylogenetic diversity present in the rumen and possibly other gastro-intestinal tract environments. New probes and quantitative PCR assays are needed to determine the distribution of the newly identified methanogen clusters in rumen microbial communities.

  18. Phylogenetic Profiling and Diversity of Bacterial Communities in the Death Valley, an Extreme Habitat in the Atacama Desert.

    Science.gov (United States)

    Piubeli, Francine; de Lourdes Moreno, María; Kishi, Luciano Takeshi; Henrique-Silva, Flavio; García, María Teresa; Mellado, Encarnación

    2015-12-01

    The Atacama Desert, one of the driest deserts in the world, represents a unique extreme environmental ecosystem to explore the bacterial diversity as it is considered to be at the dry limit for life. A 16S rRNA gene (spanning the hyper variable V3 region) library was constructed from an alkaline sample of unvegetated soil at the hyperarid margin in the Atacama Desert. A total of 244 clone sequences were used for MOTHUR analysis, which revealed 20 unique phylotypes or operational taxonomic units (OTUs). V3 region amplicons of the 16S rRNA were suitable for distinguishing the bacterial community to the genus and specie level. We found that all OTUs were affiliated with taxa representative of the Firmicutes phylum. The extremely high abundance of Firmicutes indicated that most bacteria in the soil were spore-forming survivors. In this study we detected a narrower diversity as compared to other ecological studies performed in other areas of the Atacama Desert. The reported genera were Oceanobacillus (representing the 69.5 % of the clones sequenced), Bacillus, Thalassobacillus and Virgibacillus. The present work shows physical and chemical parameters have a prominent impact on the microbial community structure. It constitutes an example of the communities adapted to live in extreme conditions caused by dryness and metal concentrations . PMID:26543264

  19. Spatial distribution of archaeal and bacterial ammonia oxidizers in the littoral buffer zone of a nitrogen-rich lake

    Institute of Scientific and Technical Information of China (English)

    Yu Wang; Guibing Zhu; Lei Ye; Xiaojuan Feng; Huub J. M. Op den Camp; Chengqing Yin

    2012-01-01

    The spatial distribution and diversity of archaeal and bacterial ammonia oxidizers (AOA and AOB) were evaluated targeting amoA genes in the gradient of a littoral buffer zone which has been identified as a hot spot for N cycling.Here we found high spatial heterogeneity in the nitrification rate and abundance of ammonia oxidizers in the five sampling sites.The bacterial amoA gene was numerically dominant in most of the surface soil but decreased dramatically in deep layers.Higher nitrification potentials were detected in two sites near the land/water interface at 4.4-6.1 μg NO2--N/(g dry weight soil.hr),while only 1.0-1.7 μg NO2- -N/(gdry weight soil·hr) was measured at other sites.The potential nitrification rates were proportional to the amoA gene abundance for AOB,hut with no significant correlation with AOA.The NH4+ concentration was the most determinative parameter for the abundance of AOB and potential nitrification rates in this study.Higher richness in the surface layer was found in the analysis of biodiversity.Phylogenetic analysis revealed that most of the bacterial amoA sequences in surface soil were affiliated with the genus of Nitrosopira while the archaeal sequences were almost equally affiliated with Candidatus ‘Nitrososphaera gargensis' and Candidatus ‘Nitrosoealdus yellowstonii'.The spatial distribution of AOA and AOB indicated that bacteria may play a more important role in nitrification in the littoral buffer zone of a N-rich lake.

  20. Physiology, phylogeny and in situ evidence for bacterial and archaeal nitrifiers in the marine sponge Aplysina aerophoba.

    Science.gov (United States)

    Bayer, Kristina; Schmitt, Susanne; Hentschel, Ute

    2008-11-01

    The potential for nitrification in the Mediterranean sponge Aplysina aerophoba was assessed using a combined physiological and molecular approach. Nitrate excretion rates in whole sponges reached values of up to 344 nmol g(-1) dry weight (wt) h(-1) (unstimulated) and 1325 nmol g(-1) dry wt h(-1) (stimulated). Addition of nitrapyrin, a nitrification-specific inhibitor, effectively inhibited nitrate excretion. Ammonium was taken up by sponges in spring and excreted in fall, the sponges thus serving as either an ammonium sink or ammonium source. Nitrosospira cluster 1 and Crenarchaeota group I.1A 16S rRNA and amoA genes were recovered from A. aerophoba and other sponges from different world's oceans. The archaeal 16S rRNA genes formed a sponge-specific subcluster, indicating that their representatives are members of the stable microbial community of sponges. On the other hand, clustering was not evident for Nitrosospira rRNA genes which is consistent with their presence in sediment and seawater samples. The presence of both Nitrosospira cluster 1 and crenarchaeal group 1 phylotypes in sponge tissue was confirmed using fluorescently labelled 16S rRNA gene probes. This study contributes to an ongoing effort to link microbial diversity with metabolic functions in the phylogenetically diverse, elusive and so far uncultivated microbial communities of marine sponges. PMID:18363713

  1. Human settlement as driver of bacterial, but not of archaeal, ammonia oxidizers abundance and community structure in tropical stream sediments

    Directory of Open Access Journals (Sweden)

    Mariana De Paula Reis

    2015-08-01

    Full Text Available Ammonia-oxidizing archaea (AOA and bacteria (AOB are a diverse and functionally important group in the nitrogen cycle. Nevertheless, AOA and AOB communities driving this process remain uncharacterized in tropical freshwater sediment. Here, the effect of human settlement on the AOA and AOB diversity and abundance have been assessed by phylogenetic and quantitative PCR analyses, using archaeal and bacterial amoA and 16S rRNA genes. Overall, each environment contained specific clades of amoA and 16S rRNA genes sequences, suggesting that selective pressures lead to AOA and AOB inhabiting distinct ecological niches. Human settlement activities, as derived from increased metal and mineral nitrogen contents, appear to cause a response among the AOB community, with Nitrosomonas taking advantage over Nitrosospira in impacted environments. We also observed a dominance of AOB over AOA in mining-impacted sediments, suggesting that AOB might be the primary drivers of ammonia oxidation in these sediments. In addition, ammonia concentrations demonstrated to be the driver for the abundance of AOA, with an inversely proportional correlation between them. Our findings also revealed the presence of novel ecotypes of Thaumarchaeota, such as those related to the obligate acidophilic Nitrosotalea devanaterra at ammonia-rich places of circumneutral pH. These data add significant new information regarding AOA and AOB from tropical freshwater sediments, albeit future studies would be required to provide additional insights into the niche differentiation among these microorganisms.

  2. Genetic diversity of Trypanosoma cruzi in bats, and multilocus phylogenetic and phylogeographical analyses supporting Tcbat as an independent DTU (discrete typing unit).

    Science.gov (United States)

    Lima, Luciana; Espinosa-Álvarez, Oneida; Ortiz, Paola A; Trejo-Varón, Javier A; Carranza, Julio C; Pinto, C Miguel; Serrano, Myrna G; Buck, Gregory A; Camargo, Erney P; Teixeira, Marta M G

    2015-11-01

    Trypanosoma cruzi is a complex of phenotypically and genetically diverse isolates distributed in six discrete typing units (DTUs) designated as TcI-TcVI. Five years ago, T. cruzi isolates from Brazilian bats showing unique patterns of traditional ribosomal and spliced leader PCRs not clustering into any of the six DTUs were designated as the Tcbat genotype. In the present study, phylogenies inferred using SSU rRNA (small subunit of ribosomal rRNA), gGAPDH (glycosomal glyceraldehyde 3-phosphate dehydrogenase) and Cytb (cytochrome b) genes strongly supported Tcbat as a monophyletic lineage prevalent in Brazil, Panama and Colombia. Providing strong support for Tcbat, sequences from 37 of 47 nuclear and 12 mitochondrial genes (retrieved from a draft genome of Tcbat) and reference strains of all DTUs available in databanks corroborated Tcbat as an independent DTU. Consistent with previous studies, multilocus analysis of most nuclear genes corroborated the evolution of T. cruzi from bat trypanosomes its divergence into two main phylogenetic lineages: the basal TcII; and the lineage clustering TcIV, the clade comprising TcIII and the sister groups TcI-Tcbat. Most likely, the common ancestor of Tcbat and TcI was a bat trypanosome. However, the results of the present analysis did not support Tcbat as the ancestor of all DTUs. Despite the insights provided by reports of TcIII, TcIV and TcII in bats, including Amazonian bats harbouring TcII, further studies are necessary to understand the roles played by bats in the diversification of all DTUs. We also demonstrated that in addition to value as molecular markers for DTU assignment, Cytb, ITS rDNA and the spliced leader (SL) polymorphic sequences suggest spatially structured populations of Tcbat. Phylogenetic and phylogeographical analyses, multiple molecular markers specific to Tcbat, and the degrees of sequence divergence between Tcbat and the accepted DTUs strongly support the definitive classification of Tcbat as a new DTU

  3. Archaeal Enzymes and Applications in Industrial Biocatalysts

    Directory of Open Access Journals (Sweden)

    Jennifer A. Littlechild

    2015-01-01

    Full Text Available Archaeal enzymes are playing an important role in industrial biotechnology. Many representatives of organisms living in “extreme” conditions, the so-called Extremophiles, belong to the archaeal kingdom of life. This paper will review studies carried by the Exeter group and others regarding archaeal enzymes that have important applications in commercial biocatalysis. Some of these biocatalysts are already being used in large scale industrial processes for the production of optically pure drug intermediates and amino acids and their analogues. Other enzymes have been characterised at laboratory scale regarding their substrate specificity and properties for potential industrial application. The increasing availability of DNA sequences from new archaeal species and metagenomes will provide a continuing resource to identify new enzymes of commercial interest using both bioinformatics and screening approaches.

  4. Assessment of microbial biomarkers with environmental genomics: a comparison of biochemical and phylogenetic indicators of microbial diversity in Yellowstone National Park

    Science.gov (United States)

    Kopf, S.; Gomes, M. L.; McAnena, A.; Vuillemin, A.; Sessions, A. L.; Spear, J. R.; International Geobiology Course 2010

    2010-12-01

    Hot spring microbial communities in Yellowstone National Park utilize diverse biochemical pathways to produce energy and survive in “simple” to “complex” systems. It has been hypothesized that these hydrothermal environments share several key attributes with environments of the Early Earth. Therefore, the characterization of microbial diversity in Yellowstone microbial mats is relevant to both modern and ancient microbial ecosystem studies. For decades, lipid biomarkers have been used to infer what microorganisms are present in microbial ecosystems. More recently, 16S ribosomal RNA gene sequencing has been utilized as the primary method to characterize microbial diversity in any environment. However, lipid biomolecules may be preserved through advanced stages of diagenesis when phylogenetic indicators are long gone. In order to better use lipid biomarkers as indicators of ancient microbial communities, it is important to understand how these biomarkers reflect modern microbial diversity as characterized by 16S rRNA gene sequences. In this study, we assessed the validity and scope of established lipid biomarkers by analyzing lipid extracts and 16S ribosomal RNA gene sequences from microbial mats at Imperial Geyser (Yellowstone National Park, Wyoming). Phyla detected in both 16S rRNA sequences and lipid biomarkers are Cholorobi, Deinococcus-Thermus, Chloroflexi, Aquificae, and Cyanobacteria. In many cases 16S rRNA data revealed the presence of a phylum without any of its diagnostic lipids being found in the respective biomarker dataset. Conversely, Cyanobacteria lipids were occasionally identified where no 16S rRNA sequences related to Cyanobacteria were detected. Most of the identified lipid biomarkers were indicative of organisms capable of autotrophy, and only few diagnostic of heterotrophic organisms, even though 16S rRNA data indicated the presence of numerous heterotrophs. Biomarkers of higher plants were also detected, indicating that allochthonous

  5. Metagenomic analysis of bacterial and archaeal assemblages in the soil-mousse surrounding a geothermal spring.

    Science.gov (United States)

    Bhatia, Sonu; Batra, Navneet; Pathak, Ashish; Joshi, Amit; Souza, Leila; Almeida, Paulo; Chauhan, Ashvini

    2015-09-01

    The soil-mousse surrounding a geothermal spring was analyzed for bacterial and archaeal diversity using 16S rRNA gene amplicon metagenomic sequencing which revealed the presence of 18 bacterial phyla distributed across 109 families and 219 genera. Firmicutes, Actinobacteria, and the Deinococcus-Thermus group were the predominant bacterial assemblages with Crenarchaeota and Thaumarchaeota as the main archaeal assemblages in this largely understudied geothermal habitat. Several metagenome sequences remained taxonomically unassigned suggesting the presence of a repertoire of hitherto undescribed microbes in this geothermal soil-mousse econiche. PMID:26484255

  6. Genetic diversity and phylogenetic relationship among Tunisian cactus species (Opuntia) as revealed by random amplified microsatellite polymorphism markers.

    Science.gov (United States)

    Bendhifi Zarroug, M; Baraket, G; Zourgui, L; Souid, S; Salhi Hannachi, A

    2015-01-01

    Opuntia ficus indica is one of the most economically important species in the Cactaceae family. Increased interest in this crop stems from its potential contribution to agricultural diversification, application in the exploitation of marginal lands, and utility as additional income sources for farmers. In Tunisia, O. ficus indica has been affected by drastic genetic erosion resulting from biotic and abiotic stresses. Thus, it is imperative to identify and preserve this germplasm. In this study, we focused on the use of random amplified microsatellite polymorphisms to assess genetic diversity among 25 representatives of Tunisian Opuntia species maintained in the collection of the National Institute of Agronomic Research of Tunisia. Seventy-two DNA markers were screened to discriminate accessions using 16 successful primer combinations. The high percentage of polymorphic band (100%), the resolving power value (5.68), the polymorphic information content (0.94), and the marker index (7.2) demonstrated the efficiency of the primers tested. Therefore, appropriate cluster analysis used in this study illustrated a divergence among the cultivars studied and exhibited continuous variation that occurred independently of geographic origin. O. ficus indica accessions did not cluster separately from the other cactus pear species, indicating that their current taxonomical classifications are not well aligned with their genetic variability or locality of origin. PMID:25730081

  7. Eukaryotic and archaeal TBP and TFB/TF(II)B follow different promoter DNA bending pathways.

    Science.gov (United States)

    Gietl, Andreas; Holzmeister, Phil; Blombach, Fabian; Schulz, Sarah; von Voithenberg, Lena Voith; Lamb, Don C; Werner, Finn; Tinnefeld, Philip; Grohmann, Dina

    2014-06-01

    During transcription initiation, the promoter DNA is recognized and bent by the basal transcription factor TATA-binding protein (TBP). Subsequent association of transcription factor B (TFB) with the TBP-DNA complex is followed by the recruitment of the ribonucleic acid polymerase resulting in the formation of the pre-initiation complex. TBP and TFB/TF(II)B are highly conserved in structure and function among the eukaryotic-archaeal domain but intriguingly have to operate under vastly different conditions. Employing single-pair fluorescence resonance energy transfer, we monitored DNA bending by eukaryotic and archaeal TBPs in the absence and presence of TFB in real-time. We observed that the lifetime of the TBP-DNA interaction differs significantly between the archaeal and eukaryotic system. We show that the eukaryotic DNA-TBP interaction is characterized by a linear, stepwise bending mechanism with an intermediate state distinguished by a distinct bending angle. TF(II)B specifically stabilizes the fully bent TBP-promoter DNA complex and we identify this step as a regulatory checkpoint. In contrast, the archaeal TBP-DNA interaction is extremely dynamic and TBP from the archaeal organism Sulfolobus acidocaldarius strictly requires TFB for DNA bending. Thus, we demonstrate that transcription initiation follows diverse pathways on the way to the formation of the pre-initiation complex. PMID:24744242

  8. Archaeal communities associated with roots of the common reed (Phragmites australis) in Beijing Cuihu Wetland.

    Science.gov (United States)

    Liu, Yin; Li, Hong; Liu, Qun Fang; Li, Yan Hong

    2015-05-01

    The richness, phylogeny and composition of archaeal community associated with the roots of common reed (Phragmites australis) growing in the Beijing Cuihu Wetland, China was investigated using a 16S rDNA library. In total, 235 individual sequences were collected, and a phylogenetic analysis revealed that 69.4 and 11.5 % of clones were affiliated with the Euryarchaeota and the Crenarchaeota, respectively. In Euryarchaeota, the archaeal community was dominated by species in following genera: Methanobacterium in the order Methanobacteriales (60.7 %); Methanoregula and Methanospirillum in the order Methanomicrobiales (20.2 %), and Methanomethylovorans, Methanosarcina and Methanosaeta in the order Methanosarcinales (17.2 %). Of 27 sequences assigned to uncultured Crenarchaeota, 22 were grouped into Group 1.3, and five grouped into Group 1.1b. Hence, the archaeal communities associated with reed roots are largely involved in methane production, and, to a lesser extent, in ammonia oxidization. Quantification of the archaeal amoA gene indicated that ammonia oxidizing archaea were more numerous in the rhizosphere soil than in the root tissue or surrounding water. A total of 19.1 % of the sequences were unclassified, suggesting that many unidentified archaea are probably involved in the reed wetland ecosystem. PMID:25739566

  9. Seasonal Effects in a Lake Sediment Archaeal Community of the Brazilian Savanna

    Directory of Open Access Journals (Sweden)

    Thiago Rodrigues

    2014-01-01

    Full Text Available The Cerrado is a biome that corresponds to 24% of Brazil’s territory. Only recently microbial communities of this biome have been investigated. Here we describe for the first time the diversity of archaeal communities from freshwater lake sediments of the Cerrado in the dry season and in the transition period between the dry and rainy seasons, when the first rains occur. Gene libraries were constructed, using Archaea-specific primers for the 16S rRNA and amoA genes. Analysis revealed marked differences between the archaeal communities found in the two seasons. I.1a and I.1c Thaumarchaeota were found in greater numbers in the transition period, while MCG Archaea was dominant on the dry season. Methanogens were only found in the dry season. Analysis of 16S rRNA sequences revealed lower diversity on the transition period. We detected archaeal amoA sequences in both seasons, but there were more OTUs during the dry season. These sequences were within the same cluster as Nitrosotalea devanaterra’s amoA gene. The principal coordinate analysis (PCoA test revealed significant differences between samples from different seasons. These results provide information on archaeal diversity in freshwater lake sediments of the Cerrado and indicates that rain is likely a factor that impacts these communities.

  10. Phylogenetic Analysis of Ethiopian HIV-1 Subtype C Near Full-Length Genomes Reveals High Intrasubtype Diversity and a Strong Geographical Cluster.

    Science.gov (United States)

    Amogne, Wondwossen; Bontell, Irene; Grossmann, Sebastian; Aderaye, Getachew; Lindquist, Lars; Sönnerborg, Anders; Neogi, Ujjwal

    2016-05-01

    In this study, we characterize HIV-1 subtype C (HIV-1C) strains at the near full-length genome (NFLG) level and perform genotypic drug resistance testing (GRT) and genotypic tropism testing (GTT) from Ethiopia (HIV-1CET). Plasma samples (n = 150) were obtained from therapy-naive individuals residing in Addis Ababa, Ethiopia in 2008. HIV-NFLG was performed in a subset of patients (n = 30). GRT (pol) and GTT (V3 env) were performed using in-house methods. GTT was analyzed by PhenoSeq-C. The phylogenetic analysis of the NLFG identified two separate clusters of HIV-1CET, although all strains formed one large overarching cluster together. At NFLG, greater diversity was found among HIV-1CET strains compared to HIV-1C strains from other geographical locations. The geographic clustering was weak in the small subgenomic (pol and env) regions. The primary drug-resistant mutations were identified at a low level (<5%). GTT identified that 12% (12/102) of the patients were predicted to be harboring X4-tropic or both R5/X4-tropic viruses. PMID:26881451

  11. Phylogenetic analysis of multiple FISH markers in oral tongue squamous cell carcinoma suggests that a diverse distribution of copy number changes is associated with poor prognosis.

    Science.gov (United States)

    Wangsa, Darawalee; Chowdhury, Salim Akhter; Ryott, Michael; Gertz, E Michael; Elmberger, Göran; Auer, Gert; Åvall Lundqvist, Elisabeth; Küffer, Stefan; Ströbel, Philipp; Schäffer, Alejandro A; Schwartz, Russell; Munck-Wikland, Eva; Ried, Thomas; Heselmeyer-Haddad, Kerstin

    2016-01-01

    Oral tongue squamous cell carcinoma (OTSCC) is associated with poor prognosis. To improve prognostication, we analyzed four gene probes (TERC, CCND1, EGFR and TP53) and the centromere probe CEP4 as a marker of chromosomal instability, using fluorescence in situ hybridization (FISH) in single cells from the tumors of sixty-five OTSCC patients (Stage I, n = 15; Stage II, n = 30; Stage III, n = 7; Stage IV, n = 13). Unsupervised hierarchical clustering of the FISH data distinguished three clusters related to smoking status. Copy number increases of all five markers were found to be correlated to non-smoking habits, while smokers in this cohort had low-level copy number gains. Using the phylogenetic modeling software FISHtrees, we constructed models of tumor progression for each patient based on the four gene probes. Then, we derived test statistics on the models that are significant predictors of disease-free and overall survival, independent of tumor stage and smoking status in multivariate analysis. The patients whose tumors were modeled as progressing by a more diverse distribution of copy number changes across the four genes have poorer prognosis. This is consistent with the view that multiple genetic pathways need to become deregulated in order for cancer to progress. PMID:26175310

  12. Protein Adaptations in Archaeal Extremophiles

    Directory of Open Access Journals (Sweden)

    Christopher J. Reed

    2013-01-01

    Full Text Available Extremophiles, especially those in Archaea, have a myriad of adaptations that keep their cellular proteins stable and active under the extreme conditions in which they live. Rather than having one basic set of adaptations that works for all environments, Archaea have evolved separate protein features that are customized for each environment. We categorized the Archaea into three general groups to describe what is known about their protein adaptations: thermophilic, psychrophilic, and halophilic. Thermophilic proteins tend to have a prominent hydrophobic core and increased electrostatic interactions to maintain activity at high temperatures. Psychrophilic proteins have a reduced hydrophobic core and a less charged protein surface to maintain flexibility and activity under cold temperatures. Halophilic proteins are characterized by increased negative surface charge due to increased acidic amino acid content and peptide insertions, which compensates for the extreme ionic conditions. While acidophiles, alkaliphiles, and piezophiles are their own class of Archaea, their protein adaptations toward pH and pressure are less discernible. By understanding the protein adaptations used by archaeal extremophiles, we hope to be able to engineer and utilize proteins for industrial, environmental, and biotechnological applications where function in extreme conditions is required for activity.

  13. Characterization of microbial diversity and community in water flooding oil reservoirs in China.

    Science.gov (United States)

    Zhao, Lingxia; Ma, Ting; Gao, Mengli; Gao, Peike; Cao, Meina; Zhu, Xudong; Li, Guoqiang

    2012-10-01

    The diversity and distribution of bacterial and archaeal communities in four different water flooding oil reservoirs with different geological properties were investigated using 16S rDNA clone library construction method. Canonical correspondence analysis was used to analyze microbial community clustering and the correlation with environmental factors. The results indicated that the diversity and abundance in the bacterial communities were significantly higher than the archaeal communities, while both of them had high similarity within the communities respectively. Phylogenetic analysis showed that of compositions of bacterial communities were distinctly different both at phylum and genus level. Proteobacteria dominated in each bacterial community, ranging from 61.35 to 75.83 %, in which α-proteobacteria and γ-proteobacteria were the main groups. In comparison to bacterial communities, the compositions of archaeal communities were similar at phylum level, while varied at genus level, and the dominant population was Methanomicrobia, ranging from 65.91 to 92.74 % in the single oil reservoir. The factor that most significantly influenced the microbial communities in these reservoirs was found to be temperature. Other environmental factors also influenced the microbial communities but not significantly. It is therefore assumed that microbial communities are formed by an accumulated effect of several factors. These results are essential for understanding ecological environment of the water flooding oil reservoirs and providing scientific guidance to the performance of MEOR technology. PMID:22806743

  14. Phylogenetic congruence and ecological coherence in terrestrial Thaumarchaeota

    OpenAIRE

    Oton, Eduard Vico; Quince, Christopher; Nicol, Graeme W.; Prosser, James I.; Gubry-Rangin, Cécile

    2015-01-01

    Thaumarchaeota form a ubiquitously distributed archaeal phylum, comprising both the ammonia-oxidising archaea (AOA) and other archaeal groups in which ammonia oxidation has not been demonstrated (including Group 1.1c and Group 1.3). The ecology of AOA in terrestrial environments has been extensively studied using either a functional gene, encoding ammonia monooxygenase subunit A (amoA) or 16S ribosomal RNA (rRNA) genes, which show phylogenetic coherence with respect to soil pH. To test phylog...

  15. Archaeal Nitrification in Hot Springs

    Science.gov (United States)

    Richter, A.; Daims, H.; Reigstad, L.; Wanek, W.; Wagner, M.; Schleper, C.

    2006-12-01

    Biological nitrification, i.e. the aerobic conversion of ammonia to nitrate via nitrite, is a major component of the global nitrogen cycle. Until recently, it was thought that the ability to aerobically oxidize ammonia was confined to bacteria of the phylum Proteobacteria. However, it has recently been shown that Archaea of the phylum Crenarchaeota are also capable of ammonia oxidation. As many Crenarchaeota are thermophilic or hyperthermophilic, and at least some of them are capable of ammonia oxidation we speculated on the existence of (hyper)thermophilic ammonia-oxidizing archaea (AOA). Using PCR primers specifically targeting the archaeal ammonia monooxygenase (amoA) gene, we were indeed able to confirm the presence of such organisms in several hot springs in Reykjadalur, Iceland. These hot springs exhibited temperatures well above 80 °C and pH values ranging from 2.0 to 4.5. To proof that nitrification actually took place under these extreme conditions, we measured gross nitrification rates by the isotope pool dilution method; we added 15N-labelled nitrate to the mud and followed the dilution of the label by nitrate production from ammonium either in situ (incubation in the hot spring) or under controlled conditions in the laboratory (at 80 °C). The nitrification rates in the hot springs ranged from 0.79 to 2.22 mg nitrate-N per L of mud and day. Controls, in which microorganisms were killed before the incubations, demonstrated that the nitrification was of biological origin. Addition of ammonium increased the gross nitrification rate approximately 3-fold, indicating that the nitrification was ammonium limited under the conditions used. Collectively, our study provides evidence that (1) AOA are present in hot springs and (2) that they are actively nitrifying. These findings have major implications for our understanding of nitrogen cycling of hot environments.

  16. Gene Acquisitions from Bacteria at the Origins of Major Archaeal Clades Are Vastly Overestimated

    Science.gov (United States)

    Groussin, Mathieu; Boussau, Bastien; Szöllõsi, Gergely; Eme, Laura; Gouy, Manolo; Brochier-Armanet, Céline; Daubin, Vincent

    2016-01-01

    In a recent article, Nelson-Sathi et al. (NS) report that the origins of major archaeal lineages (MAL) correspond to massive group-specific gene acquisitions via HGT from bacteria (Nelson-Sathi et al. 2015. Origins of major archaeal clades correspond to gene acquisitions from bacteria. Nature 517(7532):77-80.). If correct, this would have fundamental implications for the process of diversification in microbes. However, a reexamination of these data and results shows that the methodology used by NS systematically inflates the number of genes acquired at the root of each MAL, and incorrectly assumes bacterial origins for these genes. A reanalysis of their data with appropriate phylogenetic models accounting for the dynamics of gene gain and loss between lineages supports the continuous acquisition of genes over long periods in the evolution of Archaea. PMID:26541173

  17. Phylogenetic diversity of freshwater picocyanobacteria

    OpenAIRE

    Callieri, Cristiana; Coci, Manuela

    2012-01-01

    Picocyanobacteria are photosynthetic prokaryotes, coccoid or rod-shaped, with a cell diameter < 2 ?m. They are common in lakes and oceans, and abundant across a wide spectrum of trophic conditions (Callieri et al 2012). The dominant genus of freshwater picocyanobacteria is Synechococcus. Analysis of 16S rRNA gene of freshwater Synechococcus showed its polyphyletic origin, requiring better insights in the present classification of the genus and possibly a revision. We isolated more than 40 pic...

  18. Methanobacterium Dominates Biocathodic Archaeal Communities in Methanogenic Microbial Electrolysis Cells

    KAUST Repository

    Siegert, Michael

    2015-07-06

    © 2015 American Chemical Society. Methane is the primary end product from cathodic current in microbial electrolysis cells (MECs) in the absence of methanogenic inhibitors, but little is known about the archaeal communities that develop in these systems. MECs containing cathodes made from different materials (carbon brushes, or plain graphite blocks or blocks coated with carbon black and platinum, stainless steel, nickel, ferrihydrite, magnetite, iron sulfide, or molybdenum disulfide) were inoculated with anaerobic digester sludge and acclimated at a set potential of -600 mV (versus a standard hydrogen electrode). The archaeal communities on all cathodes, except those coated with platinum, were predominated by Methanobacterium (median 97% of archaea). Cathodes with platinum contained mainly archaea most similar to Methanobrevibacter. Neither of these methanogens were abundant (<0.1% of archaea) in the inoculum, and therefore their high abundance on the cathode resulted from selective enrichment. In contrast, bacterial communities on the cathode were more diverse, containing primarily δ-Proteobacteria (41% of bacteria). The lack of a consistent bacterial genus on the cathodes indicated that there was no similarly selective enrichment of bacteria on the cathode. These results suggest that the genus Methanobacterium was primarily responsible for methane production in MECs when cathodes lack efficient catalysts for hydrogen gas evolution. (Figure Presented).

  19. Phylogenetically resolving epidemiologic linkage

    Science.gov (United States)

    Romero-Severson, Ethan O.; Bulla, Ingo; Leitner, Thomas

    2016-01-01

    Although the use of phylogenetic trees in epidemiological investigations has become commonplace, their epidemiological interpretation has not been systematically evaluated. Here, we use an HIV-1 within-host coalescent model to probabilistically evaluate transmission histories of two epidemiologically linked hosts. Previous critique of phylogenetic reconstruction has claimed that direction of transmission is difficult to infer, and that the existence of unsampled intermediary links or common sources can never be excluded. The phylogenetic relationship between the HIV populations of epidemiologically linked hosts can be classified into six types of trees, based on cladistic relationships and whether the reconstruction is consistent with the true transmission history or not. We show that the direction of transmission and whether unsampled intermediary links or common sources existed make very different predictions about expected phylogenetic relationships: (i) Direction of transmission can often be established when paraphyly exists, (ii) intermediary links can be excluded when multiple lineages were transmitted, and (iii) when the sampled individuals’ HIV populations both are monophyletic a common source was likely the origin. Inconsistent results, suggesting the wrong transmission direction, were generally rare. In addition, the expected tree topology also depends on the number of transmitted lineages, the sample size, the time of the sample relative to transmission, and how fast the diversity increases after infection. Typically, 20 or more sequences per subject give robust results. We confirm our theoretical evaluations with analyses of real transmission histories and discuss how our findings should aid in interpreting phylogenetic results. PMID:26903617

  20. Diversity of Ammonia-Oxidizing Archaea and Bacteria Across Physical-Chemical Gradients in San Francisco Bay Estuary Sediments

    Science.gov (United States)

    Mosier, A. C.; Francis, C. A.

    2006-12-01

    A combination of recent metagenomic analyses and the cultivation of a novel, ammonia-oxidizing, marine crenarchaeota revealed the first evidence for nitrification within the Archaeal domain. Further genetic and metagenomic studies demonstrated the presence of ammonia-oxidizing crenarchaea in diverse marine and terrestrial environments. These discoveries challenge the currently accepted view of the global nitrogen cycle and validate the need for further research on microbial diversity and function. In particular, it is imperative to reexamine the microbial communities involved in ammonia oxidation in marine and estuarine sediments, where this process plays a pivotal role in the cycling and removal of nitrogen. Using phylogenetic analyses of ammonia monooxygenase subunit A (amoA) gene sequences, we examined the distribution and diversity of ammonia-oxidizing archaea (AOA) and bacteria (AOB) in San Francisco Bay, the largest estuary on the West coast of the United States. The highly impacted bay, encompassing nearly 178,000 km2, effectively connects two estuaries with varying physical-chemical characteristics to the Pacific Ocean. We recovered archaeal and bacterial amoA genes from 11 sites distributed throughout the bay, spanning the northern and southern estuaries and the central region where they connect to the ocean. Richness estimates varied considerably across all sites examined, with archaeal amoA estimates being generally higher than bacterial amoA. Several of the bacterial amoA libraries were represented by fewer than 3 genotypes. Archaeal amoA sequences were phylogenetically diverse and grouped within previously described sediment and soil/sediment clusters. Several sequences were closely related to the only cultivated AOA, Nitrosopumilus maritimus. Both the archaeal and bacterial amoA sequences showed significant regional specificity. Distinct populations exist in the northern and southern estuaries and sequences from the northernmost and southernmost sites

  1. Planktonic Euryarchaeota are a significant source of archaeal tetraether lipids in the ocean

    Science.gov (United States)

    Lincoln, Sara A.; Wai, Brenner; Eppley, John M.; Church, Matthew J.; Summons, Roger E.; DeLong, Edward F.

    2014-01-01

    Archaea are ubiquitous in marine plankton, and fossil forms of archaeal tetraether membrane lipids in sedimentary rocks document their participation in marine biogeochemical cycles for >100 million years. Ribosomal RNA surveys have identified four major clades of planktonic archaea but, to date, tetraether lipids have been characterized in only one, the Marine Group I Thaumarchaeota. The membrane lipid composition of the other planktonic archaeal groups—all uncultured Euryarchaeota—is currently unknown. Using integrated nucleic acid and lipid analyses, we found that Marine Group II Euryarchaeota (MG-II) contributed significantly to the tetraether lipid pool in the North Pacific Subtropical Gyre at shallow to intermediate depths. Our data strongly suggested that MG-II also synthesize crenarchaeol, a tetraether lipid previously considered to be a unique biomarker for Thaumarchaeota. Metagenomic datasets spanning 5 y indicated that depth stratification of planktonic archaeal groups was a stable feature in the North Pacific Subtropical Gyre. The consistent prevalence of MG-II at depths where the bulk of exported organic matter originates, together with their ubiquitous distribution over diverse oceanic provinces, suggests that this clade is a significant source of tetraether lipids to marine sediments. Our results are relevant to archaeal lipid biomarker applications in the modern oceans and the interpretation of these compounds in the geologic record. PMID:24946804

  2. CrAgDb--a database of annotated chaperone repertoire in archaeal genomes.

    Science.gov (United States)

    Rani, Shikha; Srivastava, Abhishikha; Kumar, Manish; Goel, Manisha

    2016-03-01

    Chaperones are a diverse class of ubiquitous proteins that assist other cellular proteins in folding correctly and maintaining their native structure. Many different chaperones cooperate to constitute the 'proteostasis' machinery in the cells. It has been proposed earlier that archaeal organisms could be ideal model systems for deciphering the basic functioning of the 'protein folding machinery' in higher eukaryotes. Several chaperone families have been characterized in archaea over the years but mostly one protein at a time, making it difficult to decipher the composition and mechanistics of the protein folding system as a whole. In order to deal with these lacunae, we have developed a database of all archaeal chaperone proteins, CrAgDb (Chaperone repertoire in Archaeal genomes). The data have been presented in a systematic way with intuitive browse and search facilities for easy retrieval of information. Access to these curated datasets should expedite large-scale analysis of archaeal chaperone networks and significantly advance our understanding of operation and regulation of the protein folding machinery in archaea. Researchers could then translate this knowledge to comprehend the more complex protein folding pathways in eukaryotic systems. The database is freely available at http://14.139.227.92/mkumar/cragdb/. PMID:26862144

  3. Previously undocumented diversity and abundance of cryptic species: a phylogenetic analysis of Indo-Pacific Arminidae Rafinesque, 1814 (Mollusca: Nudibranchia) with descriptions of 20 new species of Dermatobranchus

    Science.gov (United States)

    Gosliner, Terrence M; Fahey, Shireen J

    2011-01-01

    The phylogenetic relationships amongst the Arminidae were analysed based upon morphological characters of 58 presently described species or nudibranchs, including 35 previously described Arminidae and 20 new species of Dermatobranchus. From the literature review and anatomical examinations, 43 characters were considered for 78 taxa. These characters were polarized using Berthella canariensis as the outgroup taxon and the type species of several other genera identified from recent publications. The resulting phylogeny supports the monophyly of Arminidae, Dermatobranchus, Doridina, and Proctonotidae. The paraphyly of the Arminina is further demonstrated in this study. Two previously described, but poorly known, species of Indo-Pacific Armina are redescribed, Armina magna Baba, 1955 and Armina paucifoliata Baba, 1955. The anatomy and taxonomic status of nine previously described species of Dermatobranchus were examined in this study. The anatomy of Dermatobranchus pustulosus (van Hasselt, 1824) has been overlooked since Bergh (1888) illustrated the radula of van Hasselt's specimen. It is redescribed and its range is extended to several new localities in the western Pacific. Dermatobranchus pulcherrimus Miller & Willan, 1986 is considered here as a new synonym of Dermatobranchus rubidus (Gould, 1852). The following 20 species of Dermatobranchus are new and are described in the present paper: Dermatobranchus albineus sp. nov., Dermatobranchus arminus sp. nov., Dermatobranchus caesitius sp. nov., Dermatobranchus caeruleomaculatus sp. nov., Dermatobranchus cymatilis sp. nov., Dermatobranchus dendonephthyphagus sp. nov., Dermatobranchus diagonalis sp. nov., Dermatobranchus earlei sp. nov., Dermatobranchus fasciatus sp. nov., Dermatobranchus funiculus sp. nov., Dermatobranchus kalyptos sp. nov., Dermatobranchus kokonas sp. nov., Dermatobranchus leoni sp. nov., Dermatobranchus microphallus sp. nov., Dermatobranchus oculus sp. nov., Dermatobranchus phyllodes sp. nov

  4. Temporal Dynamics of Active Prokaryotic Nitrifiers and Archaeal Communities from River to Sea

    OpenAIRE

    Hugoni, Mylène; Agogué, Hélène; Taib, Najwa; Domaizon, Isabelle; Moné, Anne; Pierre E Galand; Bronner, Gisèle; Debroas, Didier; Mary, Isabelle

    2015-01-01

    International audience To test if different niches for potential nitrifiers exist in estuarine systems, we assessed by pyrosequencing the diversity of archaeal gene transcript markers for taxonomy (16S ribosomal RNA (rRNA)) during an entire year along a salinity gradient in surface waters of the Charente estuary (Atlantic coast, France). We further investigated the potential for estuarine prokaryotes to oxidize ammonia and hydrolyze urea by quantifying thaumarchaeal amoA and ureC and bacte...

  5. Abundance and Composition of Epiphytic Bacterial and Archaeal Ammonia Oxidizers of Marine Red and Brown Macroalgae

    OpenAIRE

    Trias, R. (Rosalía); García-Lledó A. (Arantzazu); Sánchez, N.; López-Jurado, J. L.; Hallin, S. (Sara); Bañeras, Ll. (Lluís)

    2012-01-01

    Ammonia-oxidizing bacteria (AOB) and archaea (AOA) are important for nitrogen cycling in marine ecosystems. Little is known about the diversity and abundance of these organisms on the surface of marine macroalgae, despite the algae’s potential importance to create surfaces and local oxygen-rich environments supporting ammonia oxidation at depths with low dissolved oxygen levels. We determined the abundance and composition of the epiphytic bacterial and archaeal ammonia-oxidizing communities o...

  6. Stratified active archaeal communities in the sediments of Jiulong River Estuary, China

    Directory of Open Access Journals (Sweden)

    Qianqian eLi

    2012-08-01

    Full Text Available Here the composition of total and active archaeal communities in a sediment core of Jiulong River estuary at Fujian Province, Southern China was reported. Profiles of CH4 and SO42- concentrations from the sediment core indicated the existence of a sulfate-methane transition zone (SMTZ in which sulfate reduction-coupled anaerobic oxidation of methane occurs. Accordingly, three sediment layers (16-18.5 cm, 71-73.5 cm, 161-163.5 cm from the 1.2 m sediment core were sectioned and named top, middle and bottom, respectively. Total DNA and RNA of each layer were extracted and used for clone libraries and sequence analysis of 16S rRNA genes, the reverse transcription (RT-PCR products of 16S rRNA and methyl CoM reductase alpha subunit (mcrA genes. Phylogenetic analysis indicated that archaeal communities of the three layers were dominated by the Miscellaneous Crenarchaeotal Group (MCG whose ecological functions were still unknown. The MCG could be further divided into seven subgroups, named MCG-A, B, C, D, E, F and G. MCG-A and MCG-G were the most active groups in the estuarine sediments. Known anaerobic methanotrophic archaea (ANMEs were only found as minor components in these estuarine archaeal communities. This study, together with the studies of deep subsurface sediments, would be a very good start point to target and compare the specific active archaeal groups and their roles in the dark, deep subsurface sediment environments.

  7. Archaeal communities in boreal forest tree rhizospheres respond to changing soil temperatures.

    Science.gov (United States)

    Bomberg, Malin; Münster, Uwe; Pumpanen, Jukka; Ilvesniemi, Hannu; Heinonsalo, Jussi

    2011-07-01

    Temperature has generally great effects on both the activity and composition of microbial communities in different soils. We tested the impact of soil temperature and three different boreal forest tree species on the archaeal populations in the bulk soil, rhizosphere, and mycorrhizosphere. Scots pine, silver birch, and Norway spruce seedlings were grown in forest humus microcosms at three different temperatures, 7-11.5°C (night-day temperature), 12-16°C, and 16-22°C, of which 12-16°C represents the typical mid-summer soil temperature in Finnish forests. RNA and DNA were extracted from indigenous ectomycorrhiza, non-mycorrhizal long roots, and boreal forest humus and tested for the presence of archaea by nested PCR of the archaeal 16S rRNA gene followed by denaturing gradient gel electrophoresis (DGGE) profiling and sequencing. Methanogenic Euryarchaeota belonging to Methanolobus sp. and Methanosaeta sp. were detected on the roots and mycorrhiza. The most commonly detected archaeal 16S rRNA gene sequences belonged to group I.1c Crenarchaeota, which are typically found in boreal and alpine forest soils. Interestingly, also one sequence belonging to group I.1b Crenarchaeota was detected from Scots pine mycorrhiza although sequences of this group are usually found in agricultural and forest soils in temperate areas. Tree- and temperature-related shifts in the archaeal population structure were observed. A clear decrease in crenarchaeotal DGGE band number was seen with increasing temperature, and correspondingly, the number of euryarchaeotal DGGE bands, mostly methanogens, increased. The greatest diversity of archaeal DGGE bands was detected in Scots pine roots and mycorrhizas. No archaea were detected from humus samples from microcosms without tree seedling, indicating that the archaea found in the mycorrhizosphere and root systems were dependent on the plant host. The detection of archaeal 16S rRNA gene sequences from both RNA and DNA extractions show that the

  8. DETECTING EFFECT OF PHYLOGENETIC DIVERSITY ON SEEDLING MORTALITY IN AN EVERGREEN BROAD-LEAVED FOREST IN CHINA%常绿阔叶林谱系多样性对幼苗存活率的影响

    Institute of Scientific and Technical Information of China (English)

    陈英

    2009-01-01

    密度制约机制对于维护生物多样性有非常重要的作用.随着对密度制约机制的深入研究,人们逐渐认识到:不仅在种内存在密度制约效应,亲缘关系相近的物种之间也可能表现出密度制约效应.webb在2000年提山的NRI(净种间亲缘关系指数)、NTI(净最近种间亲缘关系指数)考虑了比较全面的谱系信息,获得了广泛的应用.该文采用NRI、NTI来代表种间关系,并用Logistic回归模犁来分析了谱系因子对浙江省开化县古田山自然保护区24hm~2永久监测样地中501个幼苗样方死亡率的影响.通过对6次幼苗调查数据的分析表明:不仅相同物种密度对于幼苗的死亡率有显著影响,当密度达到一定水平时,谱系因子同样也对幼苗的死亡率有显著影响苗区中个体间的亲缘关系越近,幼苗个体的死亡率越高.%Aims Negative density dependence plays an important role in maintaining forest biodiversity. Ecologists found this mechanism operates not only between conspecifics but also between closely related heterospecifics. Our objective was to determine whether phylogenetic diversity affects seedling mortality at different scales.Methods We used net relatedness index (NRI) and nearest taxon index (NTI) to represent phylogenetic diversity and employed logistic regression modeling. We analyzed the relationship between seedling mortality and phylogenetic diversity using the seedling dynamic data from six seedling censuses of 507 seedling plots at Gutianshan Nature Reserve during May 2006 and November 2007. Important findings We found that higher density of conspecifics resulted in higher seedling mortality, and phylogenetic diversity was responsible for seedling mortality when seedling density was high (>3.46 individuals·m~(-2)).

  9. TBP Domain Symmetry in Basal and Activated Archaeal Transcription

    OpenAIRE

    Ouhammouch, Mohamed; Hausner, Winfried; Geiduschek, E Peter

    2008-01-01

    The TATA-box binding protein (TBP) is the platform for assembly of archaeal and eukaryotic transcription preinitiation complexes. Ancestral gene duplication and fusion events have produced the saddle-shaped TBP molecule, with its two direct-repeat subdomains and pseudo-two-fold symmetry. Collectively, eukaryotic TBPs have diverged from their present-day archaeal counterparts, which remain highly symmetrical. The similarity of the N- and C-halves of archaeal TBPs is especially pronounced in th...

  10. Changes in archaeal abundance and community structure along a salinity gradient in the lower Pearl River and its estuary

    Science.gov (United States)

    Zhang, C.; Wang, J.; Xie, W.; Wang, P.; Wei, Y.; Chen, S.; Zhou, X.

    2013-12-01

    Archaea occur in a wide range of habitats and across broad environmental gradients. At the global scale, salinity is known to be a major driving force for archaeal species diversity. The goal of this study was to examine changes in abundance and diversity of archaeal community DNA and membrane lipids in the water column along a salinity gradient in the lower Pearl River and estuary in the context of water/gas chemistry (pH, nitrate/nitrite, ammonia, methane, carbon dioxide). The pH increased and nitrate/nitrite and ammonia decreased from the lower Pearl River to the estuary. Methane and carbon dioxide fluxes were high in the lower Pearl River and decreased sharply in the estuary and toward the open ocean. The archaeal lipid profile exhibited abrupt changes from dominance of GDGT-0 (a glycerol diakly glycerol tetraether with zero cyclopentyl ring, which is commonly present in methanogens) to dominance of crenarchaeol (a specific biomarker for Thaumarchaeota) with increasing salinity from zero in the lower Pearl River to >0.5% in the estuary. Quantification of the 16S rRNA gene abundance using qPCR revealed a switch from bacteria-dominance to archaea-dominance and the ratio of archaeal nirK/bacterial-amoA genes had a peak value in the estuary, suggesting enhanced activity of ammonia oxidation by archaea. Pyrosequencing of archaeal 16S rRNA, amoA and nirK genes exhibited systematic variation defined by habitat types. Our current studies employ rate measurements of carbon fixation, ammonia oxidation, and nitrate reduction using isotope labeling approaches, which will allow us to link changes in archaeal community structure and ecological function.

  11. Geochemical Approach to Archaeal Ecology: δ13C of GDGTs

    Science.gov (United States)

    Lichtin, S.; Warren, C.; Pearson, A.; Pagani, M.

    2015-12-01

    Over the last decade and a half, glycerol dialkyl glycerol tetraethers (GDGTs) have increasingly been used to reconstruct environmental temperatures; proxies like TEX86 that correlate the relative abundance of these archaeal cell membrane lipids to sea surface temperature are omnipresent in paleoclimatology literature. While it has become common to make claims about past temperatures using GDGTs, our present understanding of the organisms that synthesize the compounds is still quite limited. The generally accepted theory states that microorganisms like the Thaumarchaeota modify the structure of membrane lipids to increase intermolecular interactions, strengthening the membrane at higher temperatures. Yet to date, culture experiments have been largely restricted to a single species, Nitrosopumilus maritimes, and recent studies on oceanic archaeal rRNA have revealed that these biomarkers are produced in diverse, heterogeneous, and site-specific communities. This brings up questions as to whether different subclasses of GDGTs, and all subsequent proxies, represent adaptation within a single organismal group or a shift in community composition. To investigate whether GDGTs with different chain structures, from the simple isoprenoidal GDGT-0 to Crenarchaeol with its many cyclopentane groups, are sourced from archaea with similar or disparate metabolic pathways—and if that information is inherited in GDGTs trapped in marine sediments—this study examines the stable carbon isotope values (δ13C) of GDGTs extracted from the uppermost meters of sediment in the Orca Basin, Gulf of Mexico, using spooling-wire microcombustion isotope-ratio mass spectrometer (SWiM-IRMS), tackling a fundamental assumption of the TEX86 proxy that influences the way we perceive the veracity of existing temperature records.

  12. Drivers of archaeal ammonia-oxidizing communities in soil

    Directory of Open Access Journals (Sweden)

    KaterynaZhalnina

    2012-06-01

    Full Text Available Soil ammonia-oxidizing archaea (AOA are highly abundant and play an important role in the nitrogen cycle. In addition, AOA have a significant impact on soil quality. AOA may cause nitrogen loss from soils, and the nitrate produced by AOA can lead to ground and surface water contamination, water eutrophication, and soil subsidence. The ammonia-oxidizing archaea discovered to date are classified in the phylum Thaumarchaeota. Only a few archaeal genomes are available in databases. As a result, AOA genes are not well annotated, and it is difficult to mine and identify archaeal genes within metagenomic libraries. Nevertheless, 16S rRNA and comparative analysis of ammonia monooxygenase sequences show that soils can vary greatly in the relative abundance of AOA. In some soils, AOA can comprise more than 10% of the total prokaryotic community. In other soils, AOA comprise less than 0.5% of the community. Many approaches have been used to measure the abundance and diversity of this group including DGGE, T-RFLP, q-PCR, and DNA sequencing. AOA have been studied across different soil types and various ecosystems from the Antarctic dry valleys to the tropical forests of South America to the soils near Mount Everest. Different studies have identified multiple soil factors that trigger the abundance of AOA. These factors include pH, concentration of available ammonia, organic matter content, moisture content, nitrogen content, clay content, as well as other triggers. Land use management appears to have a major effect on the abundance of AOA in soil, which may be the result of nitrogen fertilizer used in agricultural soils. This review summarizes the published results on this topic and suggests future work that will increase our understanding of how soil management and edaphoclimatic factors influence AOA.

  13. Similarities and Contrasts in the Archaeal Community of Two Japanese Mountains: Mt. Norikura Compared to Mt. Fuji.

    Science.gov (United States)

    Singh, Dharmesh; Takahashi, Koichi; Park, Jungok; Adams, Jonathan M

    2016-02-01

    The community ecology, abundance, and diversity patterns of soil archaea are poorly understood-despite the fact that they are a major branch of life that is ubiquitous and important in nitrogen cycling in terrestrial ecosystems. We set out to investigate the elevational patterns of archaeal ecology, and how these compare with other groups of organisms. Many studies of different groups of organisms (plants, birds, etc.) have shown a series of distinct communities with elevation, and often a diversity maximum in mid-elevations. We investigated the soil archaeal communities on Mt. Norikura, Japan, using 454 pyrosequencing of the 16S ribosomal RNA (rRNA) gene. There was a strong mid-elevation maximum in diversity, and a mid-elevation maximum in abundance of soil archaea 16S rRNA and amoA genes. These diversity and abundance maximums could not be correlated with any identifiable soil parameter, nor plant diversity. Discrete, predictable communities of archaea occurred at each elevational level, also not explicable in terms of pH or major nutrients. When we compared the archaeal community and diversity patterns with those found in an earlier study of Mt Fuji, both mountains showed mid-elevation maximums in diversity and abundance of archaea, possibly a result of some common environmental factor such as soil disturbance frequency. However, they showed distinct sets of archaeal communities at similar elevational sampling points. Presumably, the difference reflects their distinct geology (Norikura being andesitic, while Fuji is basaltic) and the resulting combinations of soil chemistry and environmental conditions, although no explanatory variable was found. Clearly, many soil archaea have strongly defined niches and will only occur in a narrow subset of the range of possible climate and soil conditions. The findings of a mid-elevation diversity maximum on Norikura provides a further instance of how widespread this unexplained pattern is in nature, in a wide variety of

  14. Methane metabolism in the archaeal phylum Bathyarchaeota revealed by genome-centric metagenomics.

    Science.gov (United States)

    Evans, Paul N; Parks, Donovan H; Chadwick, Grayson L; Robbins, Steven J; Orphan, Victoria J; Golding, Suzanne D; Tyson, Gene W

    2015-10-23

    Methanogenic and methanotrophic archaea play important roles in the global flux of methane. Culture-independent approaches are providing deeper insight into the diversity and evolution of methane-metabolizing microorganisms, but, until now, no compelling evidence has existed for methane metabolism in archaea outside the phylum Euryarchaeota. We performed metagenomic sequencing of a deep aquifer, recovering two near-complete genomes belonging to the archaeal phylum Bathyarchaeota (formerly known as the Miscellaneous Crenarchaeotal Group). These genomes contain divergent homologs of the genes necessary for methane metabolism, including those that encode the methyl-coenzyme M reductase (MCR) complex. Additional non-euryarchaeotal MCR-encoding genes identified in a range of environments suggest that unrecognized archaeal lineages may also contribute to global methane cycling. These findings indicate that methane metabolism arose before the last common ancestor of the Euryarchaeota and Bathyarchaeota. PMID:26494757

  15. Short tandem repeat technology has diverse applications: Individual identification, phylogenetic reconstruction and chimerism based post haematopoietic stem cell transplantation graft monitoring

    OpenAIRE

    Agrawal Suraksha; Khan Faisal; Talwar Sudha; Nityanand Sonia

    2004-01-01

    BACKGROUND: Short Tandem Repeat (STR) loci are widely considered to be effective for variety of applications including forensic applications, phylogenetic reconstruction and chimerism based post Haematopoietic Stem Cell Transplantation (HSCT) graft monitoring. For each application, specific sets of STR loci are used. AIMS: In the present study, we have attempted to use same set of STR loci for varied purposes based on their efficacy and informativity. SETTINGS AND DESIGN: Population and patie...

  16. Phylogenetic Characterization of Archaea in Saltpan Sediments

    OpenAIRE

    Ahmad, Nasier; Johri, Sarojini; Sultan, Phalisteen; Abdin, Malik Z.; Qazi, Ghulam N

    2011-01-01

    A study was undertaken to investigate the presence of archaeal diversity in saltpan sediments of Goa, India by 16S rDNA-dependent molecular phylogeny. Small subunit rRNA (16S rDNA) from saltpan sediment metagenome were amplified by polymerase chain reaction (PCR) using primers specific to the domain archaea. 10 unique phylotypes were obtained by PCR based RFLP of 16S rRNA genes using endonuclease Msp 1, which was most suitable to score the genetic diversity. These phylotypes spanned a wide ra...

  17. Prokaryotic Community Diversity Along an Increasing Salt Gradient in a Soda Ash Concentration Pond.

    Science.gov (United States)

    Simachew, Addis; Lanzén, Anders; Gessesse, Amare; Øvreås, Lise

    2016-02-01

    The effect of salinity on prokaryotic community diversity in Abijata-Shalla Soda Ash Concentration Pond system was investigated by using high-throughput 16S rRNA gene 454 pyrosequencing. Surface water and brine samples from five sites spanning a salinity range of 3.4 % (Lake Abijata) to 32 % (SP230F, crystallizer pond) were analyzed. Overall, 33 prokaryotic phyla were detected, and the dominant prokaryotic phyla accounted for more than 95 % of the reads consisting of Planctomycetes, Bacteroidetes, candidate division TM7, Deinococcus-Thermus, Firmicutes, Actinobacteria, Proteobacteria, and Euryarchaeota. Diversity indices indicated that operational taxonomic unit (OTU) richness decreases drastically with increasing salinity in the pond system. A total of 471 OTUs were found at 3.4 % salinity whereas 49 OTUs were detected in pond SP211 (25 % salinity), and only 19 OTUs in the crystallization pond at 32 % salinity (SP230F). Along the salinity gradient, archaeal community gradually replaced bacterial community. Thus, archaeal community accounted for 0.4 % in Lake Abijata while 99.0 % in pond SP230F. This study demonstrates that salinity appears to be the key environmental parameter in structuring the prokaryotic communities of haloalkaline environments. Further, it confirmed that the prokaryotic diversity in Lake Abijata is high and it harbors taxa with low or no phylogenetic similarities to existing prokaryotic taxa and thus represents novel microorganisms. PMID:26408190

  18. Short tandem repeat technology has diverse applications: Individual identification, phylogenetic reconstruction and chimerism based post haematopoietic stem cell transplantation graft monitoring

    Directory of Open Access Journals (Sweden)

    Agrawal Suraksha

    2004-07-01

    Full Text Available BACKGROUND: Short Tandem Repeat (STR loci are widely considered to be effective for variety of applications including forensic applications, phylogenetic reconstruction and chimerism based post Haematopoietic Stem Cell Transplantation (HSCT graft monitoring. For each application, specific sets of STR loci are used. AIMS: In the present study, we have attempted to use same set of STR loci for varied purposes based on their efficacy and informativity. SETTINGS AND DESIGN: Population and patient based study. MATERIALS AND METHODS: We have analyzed 5 STR loci - vWA, Tho1, FES, F13 and TPOX in 1000 North Indians. All five markers were also analyzed for chimerism based graft monitoring after HSCT in 42 HLA matched pair of patient-donor to predict the outcome of transplantation. STATISTICAL ANALYSIS: The analysis was done for Hardy Weinberg equilibrium (HWE, Heterozygosity, Polymorphism information content (PIC and Power of Exclusion and Phylogenetic assessment. RESULTS AND CONCLUSIONS: High allelic variability in term of Heterozygosity (0.68-0.76, PIC (0.66-0.74 and high Power of exclusion (0.28-0.38 indicating high forensic utility. The ensuing PC plots finely resolved three basal clusters corresponding to three geo-ethnic groups of African, Orientals, and Caucasians. In post HSCT chimerism analysis, it was found that together these markers were informative in 38 pairs (98% and were able to predict the chimerism status successfully. There is a possibility that these STR loci along with forensic and phylogenetic importance, can predict the outcome of HSCT successfully.

  19. The evolutionary history of protein fold families and proteomes confirms that the archaeal ancestor is more ancient than the ancestors of other superkingdoms

    Directory of Open Access Journals (Sweden)

    Kim Kyung Mo

    2012-01-01

    Full Text Available Abstract Background The entire evolutionary history of life can be studied using myriad sequences generated by genomic research. This includes the appearance of the first cells and of superkingdoms Archaea, Bacteria, and Eukarya. However, the use of molecular sequence information for deep phylogenetic analyses is limited by mutational saturation, differential evolutionary rates, lack of sequence site independence, and other biological and technical constraints. In contrast, protein structures are evolutionary modules that are highly conserved and diverse enough to enable deep historical exploration. Results Here we build phylogenies that describe the evolution of proteins and proteomes. These phylogenetic trees are derived from a genomic census of protein domains defined at the fold family (FF level of structural classification. Phylogenomic trees of FF structures were reconstructed from genomic abundance levels of 2,397 FFs in 420 proteomes of free-living organisms. These trees defined timelines of domain appearance, with time spanning from the origin of proteins to the present. Timelines are divided into five different evolutionary phases according to patterns of sharing of FFs among superkingdoms: (1 a primordial protein world, (2 reductive evolution and the rise of Archaea, (3 the rise of Bacteria from the common ancestor of Bacteria and Eukarya and early development of the three superkingdoms, (4 the rise of Eukarya and widespread organismal diversification, and (5 eukaryal diversification. The relative ancestry of the FFs shows that reductive evolution by domain loss is dominant in the first three phases and is responsible for both the diversification of life from a universal cellular ancestor and the appearance of superkingdoms. On the other hand, domain gains are predominant in the last two phases and are responsible for organismal diversification, especially in Bacteria and Eukarya. Conclusions The evolution of functions that are

  20. Spatial isolation and environmental factors drive distinct bacterial and archaeal communities in different types of petroleum reservoirs in China

    Science.gov (United States)

    Gao, Peike; Tian, Huimei; Wang, Yansen; Li, Yanshu; Li, Yan; Xie, Jinxia; Zeng, Bing; Zhou, Jiefang; Li, Guoqiang; Ma, Ting

    2016-02-01

    To investigate the spatial distribution of microbial communities and their drivers in petroleum reservoir environments, we performed pyrosequencing of microbial partial 16S rRNA, derived from 20 geographically separated water-flooding reservoirs, and two reservoirs that had not been flooded, in China. The results indicated that distinct underground microbial communities inhabited the different reservoirs. Compared with the bacteria, archaeal alpha-diversity was not strongly correlated with the environmental variables. The variation of the bacterial and archaeal community compositions was affected synthetically, by the mining patterns, spatial isolation, reservoir temperature, salinity and pH of the formation brine. The environmental factors explained 64.22% and 78.26% of the total variance for the bacterial and archaeal communities, respectively. Despite the diverse community compositions, shared populations (48 bacterial and 18 archaeal genera) were found and were dominant in most of the oilfields. Potential indigenous microorganisms, including Carboxydibrachium, Thermosinus, and Neptunomonas, were only detected in a reservoir that had not been flooded with water. This study indicates that: 1) the environmental variation drives distinct microbial communities in different reservoirs; 2) compared with the archaea, the bacterial communities were highly heterogeneous within and among the reservoirs; and 3) despite the community variation, some microorganisms are dominant in multiple petroleum reservoirs.

  1. Structure and lability of archaeal dehydroquinase

    International Nuclear Information System (INIS)

    The structure and thermal melting data for dehydroquinase from A. fulgidus are reported. The protein melts in vitro well below the organism’s growth temperature. Multiple sequence alignments of type I 3-dehydroquinate dehydratases (DQs; EC 4.2.1.10) show that archaeal DQs have shorter helical regions than bacterial orthologs of known structure. To investigate this feature and its relation to thermostability, the structure of the Archaeoglobus fulgidus (Af) DQ dimer was determined at 2.33 Å resolution and its denaturation temperature was measured in vitro by circular dichroism (CD) and differential scanning calorimetry (DSC). This structure, a P212121 crystal form with two 45 kDa dimers in the asymmetric unit, is the first structural representative of an archaeal DQ. Denaturation occurs at 343 ± 3 K at both low and high ionic strength and at 349 K in the presence of the substrate analog tartrate. Since the growth optimum of the organism is 356 K, this implies that the protein maintains its folded state through the participation of additional factors in vivo. The (βα)8 fold is compared with those of two previously determined type I DQ structures, both bacterial (Salmonella and Staphylococcus), which had sequence identities of ∼30% with AfDQ. Although the overall folds are the same, there are many differences in secondary structure and ionic features; the archaeal protein has over twice as many salt links per residue. The archaeal DQ is smaller than its bacterial counterparts and lower in regular secondary structure, with its eight helices being an average of one turn shorter. In particular, two of the eight normally helical regions (the exterior of the barrel) are mostly nonhelical in AfDQ, each having only a single turn of 310-helix flanked by β-strand and coil. These ‘protohelices’ are unique among evolutionarily close members of the (βα)8-fold superfamily. Structural features that may contribute to stability, in particular ionic factors, are

  2. Effect of phylogenetic diversity of velogenic Newcastle disease virus challenge on virus shedding post homologous and heterologous DNA vaccination in chickens.

    Science.gov (United States)

    Mohamed, Mahmoud H A; Abdelaziz, Adel M; Kumar, Sachin; Al-Habib, Malik A; Megahed, Mohamed M

    2016-04-01

    Newcastle disease (ND) is a highly devastating disease for the poultry industry as it causes high economic losses. In this present study, a DNA vaccine containing the F and HN surface antigens of a highly virulent Newcastle disease virus (NDV), NDV/1/Chicken/2005 (FJ939313), was successfully generated. Cell transfection test indicated that the vaccine expressed the F and HN genes in Hep-2 cells. The main objective of this study was to compare the extent of protection induced by DNA vaccination after homologous and heterologous NDV-challenge as determined by the amount of NDV shedding after challenge. NDV-antibody-negative chickens were vaccinated either once, twice or thrice intramuscularly at 7, 14 and 21 days old and were challenged 14 days post vaccination with either homologous virus (vaccine-matched velogenic viscerotropic Newcastle disease virus (vvNDV) strain, FJ939313), phylogenetically related to group VII, or a phylogenetically divergent heterologous virus (unmatched vvNDV strain, AY968809), which belongs to genogroup VI and shows 84.1% nucleotide similarity to the NDV-sequences of the DNA vaccine. Our data indicate that birds, which received a single dose of the DNA vaccine were poorly protected, and only 30-40% of these birds survived after challenge with high virus shedding titre. Multiple administration of the DNA vaccine induced high protection rates of 70-90% with reduced virus shedding compared to the non-vaccinated and challenged birds. Generally, homologous challenge led to reduced tracheal and cloacal shedding compared to the heterologous vvNDV strain. This study provides a promising approach for the control of ND in chickens using DNA vaccines, which are phylogenetically closely related to the circulating field strains. PMID:26813237

  3. Biogas production and methanogenic archaeal community in mesophilic and thermophilic anaerobic co-digestion processes.

    Science.gov (United States)

    Yu, D; Kurola, J M; Lähde, K; Kymäläinen, M; Sinkkonen, A; Romantschuk, M

    2014-10-01

    Over 258 Mt of solid waste are generated annually in Europe, a large fraction of which is biowaste. Sewage sludge is another major waste fraction. In this study, biowaste and sewage sludge were co-digested in an anaerobic digestion reactor (30% and 70% of total wet weight, respectively). The purpose was to investigate the biogas production and methanogenic archaeal community composition in the anaerobic digestion reactor under meso- (35-37 °C) and thermophilic (55-57 °C) processes and an increasing organic loading rate (OLR, 1-10 kg VS m(-3) d(-1)), and also to find a feasible compromise between waste treatment capacity and biogas production without causing process instability. In summary, more biogas was produced with all OLRs by the thermophilic process. Both processes showed a limited diversity of the methanogenic archaeal community which was dominated by Methanobacteriales and Methanosarcinales (e.g. Methanosarcina) in both meso- and thermophilic processes. Methanothermobacter was detected as an additional dominant genus in the thermophilic process. In addition to operating temperatures, the OLRs, the acetate concentration, and the presence of key substrates like propionate also affected the methanogenic archaeal community composition. A bacterial cell count 6.25 times higher than archaeal cell count was observed throughout the thermophilic process, while the cell count ratio varied between 0.2 and 8.5 in the mesophilic process. This suggests that the thermophilic process is more stable, but also that the relative abundance between bacteria and archaea can vary without seriously affecting biogas production. PMID:24837280

  4. Functional analysis of archaeal MBF1 by complementation studies in yeast

    Directory of Open Access Journals (Sweden)

    Siebers Bettina

    2011-03-01

    Full Text Available Abstract Background Multiprotein-bridging factor 1 (MBF1 is a transcriptional co-activator that bridges a sequence-specific activator (basic-leucine zipper (bZIP like proteins (e.g. Gcn4 in yeast or steroid/nuclear-hormone receptor family (e.g. FTZ-F1 in insect and the TATA-box binding protein (TBP in Eukaryotes. MBF1 is absent in Bacteria, but is well- conserved in Eukaryotes and Archaea and harbors a C-terminal Cro-like Helix Turn Helix (HTH domain, which is the only highly conserved, classical HTH domain that is vertically inherited in all Eukaryotes and Archaea. The main structural difference between archaeal MBF1 (aMBF1 and eukaryotic MBF1 is the presence of a Zn ribbon motif in aMBF1. In addition MBF1 interacting activators are absent in the archaeal domain. To study the function and therefore the evolutionary conservation of MBF1 and its single domains complementation studies in yeast (mbf1Δ as well as domain swap experiments between aMBF1 and yMbf1 were performed. Results In contrast to previous reports for eukaryotic MBF1 (i.e. Arabidopsis thaliana, insect and human the two archaeal MBF1 orthologs, TMBF1 from the hyperthermophile Thermoproteus tenax and MMBF1 from the mesophile Methanosarcina mazei were not functional for complementation of an Saccharomyces cerevisiae mutant lacking Mbf1 (mbf1Δ. Of twelve chimeric proteins representing different combinations of the N-terminal, core domain, and the C-terminal extension from yeast and aMBF1, only the chimeric MBF1 comprising the yeast N-terminal and core domain fused to the archaeal C-terminal part was able to restore full wild-type activity of MBF1. However, as reported previously for Bombyx mori, the C-terminal part of yeast Mbf1 was shown to be not essential for function. In addition phylogenetic analyses revealed a common distribution of MBF1 in all Archaea with available genome sequence, except of two of the three Thaumarchaeota; Cenarchaeum symbiosum A and Nitrosopumilus maritimus

  5. Archaeal community composition affects the function of anaerobic co-digesters in response to organic overload

    International Nuclear Information System (INIS)

    Highlights: ► Two types of methanogens are necessary to respond successfully to perturbation. ► Diversity of methanogens correlates with the VFA concentration and methane yield. ► Aggregates indicate tight spatial relationship between minerals and microorganisms. - Abstract: Microbial community diversity in two thermophilic laboratory-scale and three full-scale anaerobic co-digesters was analysed by genetic profiling based on PCR-amplified partial 16S rRNA genes. In parallel operated laboratory reactors a stepwise increase of the organic loading rate (OLR) resulted in a decrease of methane production and an accumulation of volatile fatty acids (VFAs). However, almost threefold different OLRs were necessary to inhibit the gas production in the reactors. During stable reactor performance, no significant differences in the bacterial community structures were detected, except for in the archaeal communities. Sequencing of archaeal PCR products revealed a dominance of the acetoclastic methanogen Methanosarcina thermophila, while hydrogenotrophic methanogens were of minor importance and differed additionally in their abundance between reactors. As a consequence of the perturbation, changes in bacterial and archaeal populations were observed. After organic overload, hydrogenotrophic methanogens (Methanospirillum hungatei and Methanoculleus receptaculi) became more dominant, especially in the reactor attributed by a higher OLR capacity. In addition, aggregates composed of mineral and organic layers formed during organic overload and indicated tight spatial relationships between minerals and microbial processes that may support de-acidification processes in over-acidified sludge. Comparative analyses of mesophilic stationary phase full-scale reactors additionally indicated a correlation between the diversity of methanogens and the VFA concentration combined with the methane yield. This study demonstrates that the coexistence of two types of methanogens, i

  6. Archaeal transformation of metals in the environment.

    Science.gov (United States)

    Bini, Elisabetta

    2010-07-01

    We are becoming increasingly aware of the role played by archaea in the biogeochemical cycling of the elements. Metabolism of metals is linked to fundamental metabolic functions, including nitrogen fixation, energy production, and cellular processes based on oxidoreductions. Comparative genomic analyses have shown that genes for metabolism, resistance, and detoxification of metals are widespread throughout the archaeal domain. Archaea share with other organisms strategies allowing them to utilize essential metals and maintain metal ions within a physiological range, although comparative proteomics show, in a few cases, preferences for specific genetic traits related to metals. A more in-depth understanding of the physiology of acidophilic archaea might lead to the development of new strategies for the bioremediation of metal-polluted sites and other applications, such as biomining. PMID:20455933

  7. Hyperthermophilic Archaeal Viruses as Novel Nanoplatforms

    DEFF Research Database (Denmark)

    Uldahl, Kristine Buch

    applications, Chapter I presents an in depth investigation of the hyperthermophilic archaeal virus SMV. Decisive steps in the viral life-cycle are studied with focus on the early stages of infection. TEM observations suggest that SMV1 virions enter into host cells via a fusion entry mechanism, involving three...... increase therapeutic benefit and minimize adverse effects. Virus-based nanoplatforms take advantage of the natural circulatory and targeting properties of viruses, to design therapeutics that specifically target tissues of interest in vivo. Plant-based viruses and bacteriophages are typically considered...... distinct stages; attachment, alignment, and fusion. Upon infection, the intracellular replication cycle lasts 8 h at which point the virus particles are released as spindle-shaped tailless particles. Chapter II builds on the replication and purification methods in Chapter I to study the interaction between...

  8. First insights into the diversity of gill monogeneans of 'Gnathochromis' and Limnochromis (Teleostei, Cichlidae) in Burundi: do the parasites mirror host ecology and phylogenetic history?

    Science.gov (United States)

    Kmentová, Nikol; Gelnar, Milan; Koblmüller, Stephan; Vanhove, Maarten P M

    2016-01-01

    Monogenea is one of the most species-rich groups of parasitic flatworms worldwide, with many species described only recently, which is particularly true for African monogeneans. For example, Cichlidogyrus, a genus mostly occurring on African cichlids, comprises more than 100 nominal species. Twenty-two of these have been described from Lake Tanganyika, a famous biodiversity hotspot in which many vertebrate and invertebrate taxa, including monogeneans, underwent unique and spectacular radiations. Given their often high degrees of host specificity, parasitic monogeneans were also used as a potential tool to uncover host species relationships. This study presents the first investigation of the monogenean fauna occurring on the gills of endemic 'Gnathochromis' species along the Burundese coastline of Lake Tanganyika. We test whether their monogenean fauna reflects the different phylogenetic position and ecological niche of 'Gnathochromis' pfefferi and Gnathochromis permaxillaris. Worms collected from specimens of Limnochromis auritus, a cichlid belonging to the same cichlid tribe as G. permaxillaris, were used for comparison. Morphological as well as genetic characterisation was used for parasite identification. In total, all 73 Cichlidogyrus individuals collected from 'G.' pfefferi were identified as C. irenae. This is the only representative of Cichlidogyrus previously described from 'G.' pfefferi, its type host. Gnathochromis permaxillaris is infected by a species of Cichlidogyrus morphologically very similar to C. gillardinae. The monogenean species collected from L. auritus is considered as new for science, but sample size was insufficient for a formal description. Our results confirm previous suggestions that 'G.' pfefferi as a good disperser is infected by a single monogenean species across the entire Lake Tanganyika. Although G. permaxillaris and L. auritus are placed in the same tribe, Cichlidogyrus sp. occurring on G. permaxillaris is morphologically more

  9. Seasonal Effects in a Lake Sediment Archaeal Community of the Brazilian Savanna

    OpenAIRE

    Thiago Rodrigues; Elisa Catão; Mercedes M. C. Bustamante; Quirino, Betania F.; Kruger, Ricardo H; Kyaw, Cynthia M

    2014-01-01

    The Cerrado is a biome that corresponds to 24% of Brazil’s territory. Only recently microbial communities of this biome have been investigated. Here we describe for the first time the diversity of archaeal communities from freshwater lake sediments of the Cerrado in the dry season and in the transition period between the dry and rainy seasons, when the first rains occur. Gene libraries were constructed, using Archaea-specific primers for the 16S rRNA and amoA genes. Analysis revealed marked ...

  10. [Foundations of the new phylogenetics].

    Science.gov (United States)

    Pavlinov, I Ia

    2004-01-01

    of cladogram construing and thus made phylogenetic reconstructions operational and repetitive. The above phenetic formula "kinship = similarity" appeared to be a keystone for development of the genophyletics. Within numerical phyletics, a lot of computer programs were elaborated which allow to manipulate with evolutionary scenario during phylogenetic reconstructions. They make it possible to reconstruct both clado- and semogeneses based on the same formalized methods. Multiplicity of numerical approaches indicates that, just as in the case of numerical phenetics, choice of adequate method(s) should be based on biologically sound theory. The main input of genophyletics (= molecular phylogenetics) into the new phylogenetics was due to completely new factology which makes it possible to compare directly such far distant taxa as prokaryotes and higher eukaryotes. Genophyletics is based on the theory of neutral evolution borrowed from microevolutionary theory and on the molecular clock hypothesis which is now considered largely inadequate. The future developments of genophyletics will be aimed at clarification of such fundamental (and "classical" by origin) problems as application of character and homology concepts to molecular structures. The new phylogenetics itself is differentiated into several schools caused basically by diversity of various approaches existing within each of its "roots". Cladistics makes new phylogenetics splitted into evolutionary and parsimonious ontological viewpoints. Numerical phyletics divides it into statistical and (again) parsimonious methodologies. Molecular phylogenetics is opposite by its factological basis to morphological one. The new phylogenetics has significance impact onto the "newest" systematics. From one side, it gives ontological status back to macrotaxa they have lost due to "new" systematics based on population thinking. From another side, it rejects some basical principles of classical phylogenetic (originally Linnean

  11. A user's guide to a data base of the diversity of Pseudomonas syringae and its application to classifying strains in this phylogenetic complex

    OpenAIRE

    Berge, Odile; Monteil, Caroline; Bartoli, Claudia; Chandeysson, Charlotte; Guilbaud, Caroline; Sands, David C.

    2014-01-01

    The Pseudomonas syringae complex is composed of numerous genetic lineages of strains from both agricultural and environmental habitats including habitats closely linked to the water cycle. The new insights from the discovery of this bacterial species in habitats outside of agricultural contexts per se have led to the revelation of a wide diversity of strains in this complex beyond what was known from agricultural contexts. Here, through Multi Locus Sequence Typing (MLST) of 216 strains, we id...

  12. Micro-evolutionary diversification among Indian Ocean parrots: temporal and spatial changes in phylogenetic diversity as a consequence of extinction and invasion

    OpenAIRE

    Jackson, H.; Jones, C G; Agapow, P-M; Tatayah, V; Groombridge, Jim J

    2015-01-01

    Almost 90% of global bird extinctions have occurred on islands. The loss of endemic spe- cies from island systems can dramatically alter evolutionary trajectories of insular species biodiversity, resulting in a loss of evolutionary diversity important for species adaptation to changing environments. The Western Indian Ocean islands have been the scene of evolution for a large number of endemic parrots. Since their discovery in the 16th cen- tury, many of these parrots have become extinct or h...

  13. Analyses of Genotypic Diversity among North, South, and Central American Isolates of Sugarcane Yellow Leaf Virus: Evidence for Colombian Origins and for Intraspecific Spatial Phylogenetic Variation

    OpenAIRE

    Moonan, Francis; Mirkov, T. Erik

    2002-01-01

    We have analyzed the genotypic diversity of Sugarcane yellow leaf virus (SCYLV) collected from North, South, and Central America by fingerprinting assays and selective cDNA cloning and sequencing. One group of isolates from Colombia, designated the C-population, has been identified as residing at the root node between a separable superpopulation structure of SCYLV and other members of the family Luteoviridae, indicating that the progenitor viruses of the North, South, and Central American iso...

  14. Phylogenomic Dating-The Relative Antiquity of Archaeal Metabolic and Physiological Traits

    Science.gov (United States)

    Blank, Carrine E.

    2009-03-01

    Ancestral trait reconstruction was used to identify the relative ancestry of metabolic and physiological traits in the archaeal domain of life. First, well-resolved phylogenetic trees were inferred with multiple gene sequences obtained from whole genome sequences. Next, metabolic and physiological traits were coded into characters, and ancestral state reconstruction was used to identify ancient and derived traits. Traits inferred to be ancient included sulfur reduction, methanogenesis, and hydrogen oxidation. By using the articulation of the “oxygen age constraint,” several other traits were inferred to have arisen at or after 2.32 Ga: aerobic respiration, nitrate reduction, sulfate reduction, thiosulfate reduction, sulfur oxidation, and sulfide oxidation. Complex organic metabolism appeared to be nearly as ancient as autotrophy. Hyperthermophily was ancestral, while hyperacidophily and extreme halophily likely arose after 2.32 Ga. The ancestral euryarchaeote was inferred to have been a hyperthermophilic marine methanogen that lived in a deep-sea hydrothermal vent. In contrast, the ancestral crenarchaeote was most likely a hyperthermophilic sulfur reducer that lived in a slightly acidic terrestrial environment, perhaps a fumarole. Cross-colonization of these habitats may not have occurred until after 2.32 Ga, which suggests that both archaeal lineages exhibited niche specialization on early Earth for a protracted period of time.

  15. Phylogenetic trees in bioinformatics

    Energy Technology Data Exchange (ETDEWEB)

    Burr, Tom L [Los Alamos National Laboratory

    2008-01-01

    Genetic data is often used to infer evolutionary relationships among a collection of viruses, bacteria, animal or plant species, or other operational taxonomic units (OTU). A phylogenetic tree depicts such relationships and provides a visual representation of the estimated branching order of the OTUs. Tree estimation is unique for several reasons, including: the types of data used to represent each OTU; the use ofprobabilistic nucleotide substitution models; the inference goals involving both tree topology and branch length, and the huge number of possible trees for a given sample of a very modest number of OTUs, which implies that fmding the best tree(s) to describe the genetic data for each OTU is computationally demanding. Bioinformatics is too large a field to review here. We focus on that aspect of bioinformatics that includes study of similarities in genetic data from multiple OTUs. Although research questions are diverse, a common underlying challenge is to estimate the evolutionary history of the OTUs. Therefore, this paper reviews the role of phylogenetic tree estimation in bioinformatics, available methods and software, and identifies areas for additional research and development.

  16. Divergent responses of methanogenic archaeal communities in two rice cultivars to elevated ground-level O3.

    Science.gov (United States)

    Zhang, Jianwei; Tang, Haoye; Zhu, Jianguo; Lin, Xiangui; Feng, Youzhi

    2016-06-01

    Inhibitive effect of elevated ground-level ozone (O3) on paddy methane (CH4) emission varies with rice cultivars. However, little information is available on its microbial mechanism. For this purpose, the responses of methane-metabolizing microorganisms, methanogenic archaea and methanotrophic bacteria to O3 pollution were investigated in the O3-tolerant (YD6) and the O3-sensitive (IIY084) cultivars at two rice growth stages in Free Air Concentration Elevation of O3 (O3-FACE) system of China. It was found that O3 pollution didn't change the abundances of Type I and Type II methanotrophic bacteria at two rice stages. For methanogenic archaea, their abundances in both cultivars were decreased by O3 pollution at the tillering stage. Furthermore, a greater negative influence on methanogenic archaeal community was observed on IIY084 than on YD6: at tillering stage, the alpha diversity indices of methanogenic archaeal community in IIY084 was decreased to a greater extent than in YD6; IIY084 shifted methanogenic archaeal community composition and decreased the abundances and the diversities of Methanosarcinaceae and Methanosaetaceae as well as the abundance of Methanomicrobiales, while the diversity of Methanocellaceae were increased in YD6. These findings indicate that the variations in the responses of paddy CH4 emission to O3 pollution between cultivars could result from the divergent responses of their methanogenic archaea. PMID:26895536

  17. A Method for Identification of Selenoprotein Genes in Archaeal Genomes

    Institute of Scientific and Technical Information of China (English)

    Mingfeng Li; Yanzhao Huang; Yi Xiao

    2009-01-01

    The genetic codon UGA has a dual function: serving as a terminator and encoding selenocysteine. However, most popular gene annotation programs only take it as a stop signal, resulting in misannotation or completely missing selenoprotein genes. We developed a computational method named Asec-Prediction that is specific for the prediction of archaeal selenoprotein genes. To evaluate its effectiveness, we first applied it to 14 archaeal genomes with previously known selenoprotein genes, and Asec-Prediction identified all reported selenoprotein genes without redundant results. When we applied it to 12 archaeal genomes that had not been researched for selenoprotein genes, Asec-Prediction detected a novel selenoprotein gene in Methanosarcina acetivorans. Further evidence was also collected to support that the predicted gene should be a real selenoprotein gene. The result shows that Asec-Prediction is effective for the prediction of archaeal selenoprotein genes.

  18. A new species of Andean frog of the genus Bryophryne from southern Peru Anura: Craugastoridae) and its phylogenetic position, with notes on the diversity of the genus.

    Science.gov (United States)

    Chaparro, Juan C; Padial, José M; Gutiérrez, Roberto C; De La Riva, Ignacio

    2015-01-01

    We describe a new species of terrestrial frog of the genus Bryophryne (Anura: Craugastoridae) from the wet puna and elfin forests of the Amazonian versant of the Andes. The new species seems to be restricted to high altitude environments at elevations between 3506-3651 m in the area now protected by Megantoni National Sanctuary and Manu National Park (Distrito de Echarate, Provincia La Convención, Departamento Cusco, Peru). The new species is characterized by lacking vomerine processes of vomers, by having tympanic annulus and tympanic membrane not evident through the skin, smooth dorsal skin with scattered warts, conspicuous dorsolateral, middorsal, and occipital folds, warty flanks, areolate skin on ventral surfaces of the body, and by lacking finger and toe fringes and basal web on feet. In life, specimens have bright and highly variable dorsal coloration that ranges from olive-green to red with variable combinations of red or orange marks (red or orange in the green form and olive-green in the red form). Molecular phylogenetic analyses of mitochondrial and nuclear DNA place the new species within the genus Bryophryne and as sister group of B. cophites. Bryophryne bustamantei, also sequenced for this study, is found as the sister group of the clade formed by B. cophites and the new species. Bryophryne is found as sister group of Psychrophrynella in maximum likelihood analyses and as the sister group of a large clade of holoadenines in parsimony analyses. The genus Bryophryne now contains nine species, all of them distributed along the Cordillera Oriental of the Peruvian Andes, southeast of the Apurimac River valley. PMID:26250261

  19. Archaeal and Bacterial Communities Associated with the Surface Mucus of Caribbean Corals Differ in Their Degree of Host Specificity and Community Turnover Over Reefs

    Science.gov (United States)

    Frade, Pedro R.; Roll, Katharina; Bergauer, Kristin; Herndl, Gerhard J.

    2016-01-01

    Comparative studies on the distribution of archaeal versus bacterial communities associated with the surface mucus layer of corals have rarely taken place. It has therefore remained enigmatic whether mucus-associated archaeal and bacterial communities exhibit a similar specificity towards coral hosts and whether they vary in the same fashion over spatial gradients and between reef locations. We used microbial community profiling (terminal-restriction fragment length polymorphism, T-RFLP) and clone library sequencing of the 16S rRNA gene to compare the diversity and community structure of dominant archaeal and bacterial communities associating with the mucus of three common reef-building coral species (Porites astreoides, Siderastrea siderea and Orbicella annularis) over different spatial scales on a Caribbean fringing reef. Sampling locations included three reef sites, three reef patches within each site and two depths. Reference sediment samples and ambient water were also taken for each of the 18 sampling locations resulting in a total of 239 samples. While only 41% of the bacterial operational taxonomic units (OTUs) characterized by T-RFLP were shared between mucus and the ambient water or sediment, for archaeal OTUs this percentage was 2-fold higher (78%). About half of the mucus-associated OTUs (44% and 58% of bacterial and archaeal OTUs, respectively) were shared between the three coral species. Our multivariate statistical analysis (ANOSIM, PERMANOVA and CCA) showed that while the bacterial community composition was determined by habitat (mucus, sediment or seawater), host coral species, location and spatial distance, the archaeal community composition was solely determined by the habitat. This study highlights that mucus-associated archaeal and bacterial communities differ in their degree of community turnover over reefs and in their host-specificity. PMID:26788724

  20. Archaeal and Bacterial Communities Associated with the Surface Mucus of Caribbean Corals Differ in Their Degree of Host Specificity and Community Turnover Over Reefs.

    Directory of Open Access Journals (Sweden)

    Pedro R Frade

    Full Text Available Comparative studies on the distribution of archaeal versus bacterial communities associated with the surface mucus layer of corals have rarely taken place. It has therefore remained enigmatic whether mucus-associated archaeal and bacterial communities exhibit a similar specificity towards coral hosts and whether they vary in the same fashion over spatial gradients and between reef locations. We used microbial community profiling (terminal-restriction fragment length polymorphism, T-RFLP and clone library sequencing of the 16S rRNA gene to compare the diversity and community structure of dominant archaeal and bacterial communities associating with the mucus of three common reef-building coral species (Porites astreoides, Siderastrea siderea and Orbicella annularis over different spatial scales on a Caribbean fringing reef. Sampling locations included three reef sites, three reef patches within each site and two depths. Reference sediment samples and ambient water were also taken for each of the 18 sampling locations resulting in a total of 239 samples. While only 41% of the bacterial operational taxonomic units (OTUs characterized by T-RFLP were shared between mucus and the ambient water or sediment, for archaeal OTUs this percentage was 2-fold higher (78%. About half of the mucus-associated OTUs (44% and 58% of bacterial and archaeal OTUs, respectively were shared between the three coral species. Our multivariate statistical analysis (ANOSIM, PERMANOVA and CCA showed that while the bacterial community composition was determined by habitat (mucus, sediment or seawater, host coral species, location and spatial distance, the archaeal community composition was solely determined by the habitat. This study highlights that mucus-associated archaeal and bacterial communities differ in their degree of community turnover over reefs and in their host-specificity.

  1. Archaeal and Bacterial Communities Associated with the Surface Mucus of Caribbean Corals Differ in Their Degree of Host Specificity and Community Turnover Over Reefs.

    Science.gov (United States)

    Frade, Pedro R; Roll, Katharina; Bergauer, Kristin; Herndl, Gerhard J

    2016-01-01

    Comparative studies on the distribution of archaeal versus bacterial communities associated with the surface mucus layer of corals have rarely taken place. It has therefore remained enigmatic whether mucus-associated archaeal and bacterial communities exhibit a similar specificity towards coral hosts and whether they vary in the same fashion over spatial gradients and between reef locations. We used microbial community profiling (terminal-restriction fragment length polymorphism, T-RFLP) and clone library sequencing of the 16S rRNA gene to compare the diversity and community structure of dominant archaeal and bacterial communities associating with the mucus of three common reef-building coral species (Porites astreoides, Siderastrea siderea and Orbicella annularis) over different spatial scales on a Caribbean fringing reef. Sampling locations included three reef sites, three reef patches within each site and two depths. Reference sediment samples and ambient water were also taken for each of the 18 sampling locations resulting in a total of 239 samples. While only 41% of the bacterial operational taxonomic units (OTUs) characterized by T-RFLP were shared between mucus and the ambient water or sediment, for archaeal OTUs this percentage was 2-fold higher (78%). About half of the mucus-associated OTUs (44% and 58% of bacterial and archaeal OTUs, respectively) were shared between the three coral species. Our multivariate statistical analysis (ANOSIM, PERMANOVA and CCA) showed that while the bacterial community composition was determined by habitat (mucus, sediment or seawater), host coral species, location and spatial distance, the archaeal community composition was solely determined by the habitat. This study highlights that mucus-associated archaeal and bacterial communities differ in their degree of community turnover over reefs and in their host-specificity. PMID:26788724

  2. Structure and Cell Biology of Archaeal Virus STIV

    OpenAIRE

    Fu, Chi-yu; Johnson, John E.

    2012-01-01

    Recent investigations of archaeal viruses have revealed novel features of their structures and life cycles when compared to eukaryotic and bacterial viruses, yet there are structure-based unifying themes suggesting common ancestral relationships among dsDNA viruses in the three kingdoms of life. Sulfolobus solfataricus and the infecting virus Sulfolobus turreted icosahedral virus (STIV) is one of the well-established model systems to study archaeal virus replication and viral-host interaction...

  3. The archaeal Sec-dependent protein translocation pathway.

    OpenAIRE

    Bolhuis, Albert

    2004-01-01

    Over the past three decades, transport of proteins across cellular membranes has been studied extensively in various model systems. One of the major transport routes, the so-called Sec pathway, is conserved in all domains of life. Very little is known about this pathway in the third domain of life, archaea. The core components of the archaeal, bacterial and eucaryal Sec machinery are similar, although the archaeal components appear more closely related to their eucaryal counterparts. Interest...

  4. Diversity of Sarcocystis spp shed by opossums in Brazil inferred with phylogenetic analysis of DNA coding ITS1, cytochrome B, and surface antigens.

    Science.gov (United States)

    Valadas, Samantha Y O B; da Silva, Juliana I G; Lopes, Estela Gallucci; Keid, Lara B; Zwarg, Ticiana; de Oliveira, Alice S; Sanches, Thaís C; Joppert, Adriana M; Pena, Hilda F J; Oliveira, Tricia M F S; Ferreira, Helena L; Soares, Rodrigo M

    2016-05-01

    Although few species of Sarcocystis are known to use marsupials of the genus Didelphis as definitive host, an extensive diversity of alleles of surface antigen genes (sag2, sag3, and sag4) has been described in samples of didelphid opossums in Brazil. In this work, we studied 25 samples of Sarcocystis derived from gastrointestinal tract of opossums of the genus Didelphis by accessing the variability of sag2, sag3, sag4, gene encoding cytochrome b (cytB) and first internal transcribed spacer (ITS1). Reference samples of Sarcocystis neurona (SN138) and Sarcocystis falcatula (SF1) maintained in cell culture were also analyzed. We found four allele variants of cytB, seven allele variants of ITS1, 10 allele variants of sag2, 13 allele variants of sag3, and 6 allele variants of sag4. None of the sporocyst-derived sequences obtained from Brazilian opossums revealed 100% identity to SN138 at cytB gene, nor to SN138 or SF1 at ITS1 locus. In addition, none of the sag alleles were found identical to either SF1 or SN138 homologous sequences, and a high number of new sag allele types were found other than those previously described in Brazil. Out of ten sag2 alleles, four are novel, while eight out of 13 sag3 alleles are novel and one out of six sag4 alleles is novel. Further studies are needed to clarify if such a vast repertoire of allele variants of Sarcocystis is the consequence of re-assortments driven by sexual exchange, in order to form individuals with highly diverse characteristics, such as pathogenicity, host spectrum, among others or if it only represents allele variants of different species with different biological traits. PMID:26905780

  5. Phylogenetic structure in tropical hummingbird communities

    DEFF Research Database (Denmark)

    Graham, Catherine H; Parra, Juan L; Rahbek, Carsten;

    2009-01-01

    sustaining an expensive means of locomotion at high elevations. We found that communities in the lowlands on opposite sides of the Andes tend to be phylogenetically similar despite their large differences in species composition, a pattern implicating the Andes as an important dispersal barrier. In contrast......How biotic interactions, current and historical environment, and biogeographic barriers determine community structure is a fundamental question in ecology and evolution, especially in diverse tropical regions. To evaluate patterns of local and regional diversity, we quantified the phylogenetic...... composition of 189 hummingbird communities in Ecuador. We assessed how species and phylogenetic composition changed along environmental gradients and across biogeographic barriers. We show that humid, low-elevation communities are phylogenetically overdispersed (coexistence of distant relatives), a pattern...

  6. Phylogenetic diversity of nitrogenase (nifH) genes in deep-sea and hydrothermal vent environments of the Juan de Fuca Ridge.

    Science.gov (United States)

    Mehta, Mausmi P; Butterfield, David A; Baross, John A

    2003-02-01

    The subseafloor microbial habitat associated with typical unsedimented mid-ocean-ridge hydrothermal vent ecosystems may be limited by the availability of fixed nitrogen, inferred by the low ammonium and nitrate concentrations measured in diffuse hydrothermal fluid. Dissolved N2 gas, the largest reservoir of nitrogen in the ocean, is abundant in deep-sea and hydrothermal vent fluid. In order to test the hypothesis that biological nitrogen fixation plays an important role in nitrogen cycling in the subseafloor associated with unsedimented hydrothermal vents, degenerate PCR primers were designed to amplify the nitrogenase iron protein gene nifH from hydrothermal vent fluid. A total of 120 nifH sequences were obtained from four samples: a nitrogen-poor diffuse vent named marker 33 on Axial Volcano, sampled twice over a period of 1 year as its temperature decreased; a nitrogen-rich diffuse vent near Puffer on Endeavour Segment; and deep seawater with no detectable hydrothermal plume signal. Subseafloor nifH genes from marker 33 and Puffer are related to anaerobic clostridia and sulfate reducers. Other nifH genes unique to the vent samples include proteobacteria and divergent Archaea. All of the nifH genes from the deep-seawater sample are most closely related to the thermophilic, anaerobic archaeon Methanococcus thermolithotrophicus (77 to 83% amino acid similarity). These results provide the first genetic evidence of potential nitrogen fixers in hydrothermal vent environments and indicate that at least two sources contribute to the diverse assemblage of nifH genes detected in hydrothermal vent fluid: nifH genes from an anaerobic, hot subseafloor and nifH genes from cold, oxygenated deep seawater. PMID:12571018

  7. Crystal structure of the S. solfataricus archaeal exosome reveals conformational flexibility in the RNA-binding ring.

    Directory of Open Access Journals (Sweden)

    Changrui Lu

    Full Text Available BACKGROUND: The exosome complex is an essential RNA 3'-end processing and degradation machinery. In archaeal organisms, the exosome consists of a catalytic ring and an RNA-binding ring, both of which were previously reported to assume three-fold symmetry. METHODOLOGY/PRINCIPAL FINDINGS: Here we report an asymmetric 2.9 A Sulfolobus solfataricus archaeal exosome structure in which the three-fold symmetry is broken due to combined rigid body and thermal motions mainly within the RNA-binding ring. Since increased conformational flexibility was also observed in the RNA-binding ring of the related bacterial PNPase, we speculate that this may reflect an evolutionarily conserved mechanism to accommodate diverse RNA substrates for degradation. CONCLUSION/SIGNIFICANCE: This study clearly shows the dynamic structures within the RNA-binding domains, which provides additional insights on mechanism of asymmetric RNA binding and processing.

  8. Trophic phylogenetics: evolutionary influences on body size, feeding, and species associations in grassland arthropods.

    Science.gov (United States)

    Lind, Eric M; Vincent, John B; Weiblen, George D; Cavender-Bares, Jeannine; Borer, Elizabeth T

    2015-04-01

    Contemporary animal-plant interactions such as herbivory are widely understood to be shaped by evolutionary history. Yet questions remain about the role of plant phylogenetic diversity in generating and maintaining herbivore diversity, and whether evolutionary relatedness of producers might predict the composition of consumer communities. We tested for evidence of evolutionary associations among arthropods and the plants on which they were found, using phylogenetic analysis of naturally occurring arthropod assemblages sampled from a plant-diversity manipulation experiment. Considering phylogenetic relationships among more than 900 arthropod consumer taxa and 29 plant species in the experiment, we addressed several interrelated questions. First, our results support the hypothesis that arthropod functional traits such as body size and trophic role are phylogenetically conserved in community ecological samples. Second, herbivores tended to cooccur with closer phylogenetic relatives than would be expected at random, whereas predators and parasitoids did not show phylogenetic association patterns. Consumer specialization, as measured by association through time with monocultures of particular host plant species, showed significant phylogenetic signal, although the. strength of this association varied among plant species. Polycultures of phylogenetically dissimilar plant species supported more phylogenetically dissimilar consumer communities than did phylogenetically similar polycultures. Finally, we separated the effects of plant species richness and relatedness in predicting the phylogenetic distribution of the arthropod assemblages in this experiment. The phylogenetic diversity of plant communities predicted the phylogenetic diversity of herbivore communities even after accounting for plant species richness. The phylogenetic diversity of secondary consumers differed by guild, with predator phylogenetic diversity responding to herbivore relatedness, while parasitoid

  9. Archaeal-eubacterial mergers in the origin of Eukarya: phylogenetic classification of life.

    OpenAIRE

    Margulis, L

    1996-01-01

    A symbiosis-based phylogeny leads to a consistent, useful classification system for all life. "Kingdoms" and "Domains" are replaced by biological names for the most inclusive taxa: Prokarya (bacteria) and Eukarya (symbiosis-derived nucleated organisms). The earliest Eukarya, anaerobic mastigotes, hypothetically originated from permanent whole-cell fusion between members of Archaea (e.g., Thermoplasma-like organisms) and of Eubacteria (e.g., Spirochaeta-like organisms). Molecular biology, life...

  10. Archaeal-eubacterial mergers in the origin of Eukarya: phylogenetic classification of life

    Science.gov (United States)

    Margulis, L.

    1996-01-01

    A symbiosis-based phylogeny leads to a consistent, useful classification system for all life. "Kingdoms" and "Domains" are replaced by biological names for the most inclusive taxa: Prokarya (bacteria) and Eukarya (symbiosis-derived nucleated organisms). The earliest Eukarya, anaerobic mastigotes, hypothetically originated from permanent whole-cell fusion between members of Archaea (e.g., Thermoplasma-like organisms) and of Eubacteria (e.g., Spirochaeta-like organisms). Molecular biology, life-history, and fossil record evidence support the reunification of bacteria as Prokarya while subdividing Eukarya into uniquely defined subtaxa: Protoctista, Animalia, Fungi, and Plantae.

  11. Archaeal Distribution in Moonmilk Deposits from Alpine Caves and Their Ecophysiological Potential.

    Science.gov (United States)

    Reitschuler, Christoph; Spötl, Christoph; Hofmann, Katrin; Wagner, Andreas O; Illmer, Paul

    2016-04-01

    (Alpine) caves are, in general, windows into the Earth's subsurface. Frequently occurring structures in caves such as moonmilk (secondary calcite deposits) offer the opportunity to study intraterrestrial microbial communities, adapted to oligotrophic and cold conditions. This is an important research field regarding the dimensions of subsurface systems and cold regions on Earth. On a methodological level, moonmilk deposits from 11 caves in the Austrian Alps were collected aseptically and investigated using a molecular (qPCR and DGGE sequencing-based) methodology in order to study the occurrence, abundance, and diversity of the prevailing native Archaea community. Furthermore, these Archaea were enriched in complex media and studied regarding their physiology, with a media selection targeting different physiological requirements, e.g. methanogenesis and ammonia oxidation. The investigation of the environmental samples showed that all moonmilk deposits were characterized by the presence of the same few habitat-specific archaeal species, showing high abundances and constituting about 50 % of the total microbial communities. The largest fraction of these Archaea was ammonia-oxidizing Thaumarchaeota, while another abundant group was very distantly related to extremophilic Euryarchaeota (Moonmilk Archaea). The archaeal community showed a depth- and oxygen-dependent stratification. Archaea were much more abundant (around 80 %), compared to bacteria, in the actively forming surface part of moonmilk deposits, decreasing to about 5 % down to the bedrock. Via extensive cultivation efforts, it was possible to enrich the enigmatic Moonmilk Archaea and also AOA significantly above the level of bacteria. The most expedient prerequisites for cultivating Moonmilk Archaea were a cold temperature, oligotrophic conditions, short incubation times, a moonmilk surface inoculum, the application of erythromycin, and anaerobic (microaerophilic) conditions. On a physiological level, it

  12. 海岸带沉积物中氮循环功能微生物多样性%Phylogenetic and functional diversity of nitrogen cycling microbes in coastal sediments

    Institute of Scientific and Technical Information of China (English)

    龚骏; 宋延静; 张晓黎

    2013-01-01

    海岸带生境类型多样,环境梯度明显,是研究微生物多样性、群落结构与功能关系及调控机制的天然实验场.沉积物是海岸带环境中营养盐再生与转化发生的重要场所,其中多种微生物类群在氮素循环过程中扮演重要角色.本文重点介绍海岸带沉积物中固氮菌、氨氧化菌、厌氧氨氧化菌、反硝化与硝酸盐铵化微生物的基于16SrRNA基因的物种多样性和基于关键酶基因nifH、amoA、narG、nirS、nirK、nosZ、nrfA、hzo、hzs等的功能多样性;总结了在海岸带特有生境(如河口、潮间带、海草藻床、红树林、盐沼、珊瑚礁、浅海等)及污染胁迫、生物扰动等条件下各功能类群的群落组成特征及时空变化规律,并提出今后需要重点关注新的培养技术和方法的开发,以进一步提高微生物的可培养性,将单细胞基因组测序与分析技术、DNA和RNA结合起来研究,以全面了解氮循环微生物多样性、参与介导硝酸盐铵化过程的微生物多样性等方面.%The coastal zone contains diverse habitats which are usually characterized by strong environmental gradients (e.g.salinity,nutrients and pollutants).This makes the coastal zone an ideal experimental laboratory for describing microbial diversity and testing hypotheses on community structure,function and control.Coastal sediment is of significance in nutrient regeneration and transformation involving different assemblages of microbes in the nitrogen cycle.This review focuses on 16S rRNA gene-based phylogenetic diversity and the key enzyme encoding gene-based (e.g.nifH,amoA,narG,nirS,nirK,nosZ,nrfA,hzo and hzs) functional diversity of nitrogen fixing,ammonia oxidizing and anaerobic ammonia oxidation (Anammox) bacteria as well as bacteria and fungi involved in denitrification and dissimilatory nitrate reduction to ammonium (DNRA).Characteristics of community composition and diversity of nitrogen cycling microbes in different

  13. 丛生盔形珊瑚共附生可培养真菌多样性分析%Phylogenetic diversity analysis of cultured symbiotic fungi of Galaxea fascicularis L.

    Institute of Scientific and Technical Information of China (English)

    徐佳; 陈彬; 雷晓凌; 佘志刚; 肖碧红

    2011-01-01

    To study the diversity of cultured symbiotic fungi isolated from Galaxea fascicularis L. in the South China Sea. By dilution plate technique and ITS-rDNA sequence analysis to research the diversity of the cultured symbiotic fungi with the coral, determined sequences data were submitted to GenBank and compared with those known sequences. Phylogenetic tree were built up with MEGA 4.0 program. 19 different morphological strains were isolated from surface and inner of the coral Galaxea fascicularis. ITS-rDNA sequences analysis showed that, symbiosis cultured fungi mainly included Aspergillus sp., Cladosporium sp., Xylariales sp., Penicillium sp., Stachybotrys sp., Gibberella moniliformis, Fusarium sp. etc. The similarity of strain 4-13 sequence to the most closely related sequences in GenBank was only 89%. It is concluded that there are diverse fungal symbionts with coral Galaxea fascicularis, which have potential new microorganism resources, deserved for further study.%旨在研究珊瑚共附生可培养真菌多样性.运用稀释平板法和基于ITS-rDNA基因序列的系统发育分析对珊瑚共附生可培养真菌多样性进行研究,将所得到的基因序列与NCBI数据库GenBank中的序列进行相似性比较并构建系统发育树.实验中从丛生盔形珊瑚表面和内部共分离得到19株菌落形态各异的真菌.ITS-rDNA序列分析及形态学鉴定表明,丛生盔形珊瑚共附生真菌主要包括曲霉菌Aspergillus sp.、枝孢霉菌Cladosporium sp.、炭角菌Xylariales sp.、青霉菌Penicilliumsp.、葡萄穗霉菌Stachybotrys sp.,赤霉菌Gibberella moniliformis、镰刀霉菌Fusarium sp.等.分离得到的菌株中,4-13与GenBank中已报道的基因序列的相似性仅为89%.结果表明,与丛生盔形珊瑚共附生的可培养真菌较为丰富,是潜在的新的微生物菌种资源,具有进一步研究的价值.

  14. Genetic diversity and phylogenetic analysis of Citrus (L from north-east India as revealed by meiosis, and molecular analysis of internal transcribed spacer region of rDNA

    Directory of Open Access Journals (Sweden)

    Marlykynti Hynniewta

    2014-12-01

    Full Text Available The north-eastern region of India is reported to be the center of origin and rich in diversity of Citrus (L. species, where some wild and endangered species namely Citrus indica, Citrus macroptera, Citrus latipes, Citrus ichagensis and Citrus assamensis exist in their natural and undisturbed habitat. In order to have comprehensive information about the extent of genetic variability and the occurrence of cryptic genomic hybridity between and within various Citrus species, a combined approach involving morphological, cytogenetical and molecular approaches were adopted in the present study. Cytogenetic approaches are known to resolve taxonomic riddles in a more efficient manner, by clearly delineating taxa at species and sub species levels. Male meiotic studies revealed a gametic chromosome number of n = 9, without any evidence of numerical variations. Bivalents outnumbered all other types of associations in pollen mother cells (PMCs analyzed at diplotene, diakinesis and metaphase I. Univalents were frequently encountered in nine species presently studied, though their presence appropriately did not influence the distributional pattern of the chromosomes at anaphases I and II. The molecular approaches for phylogenetic analysis based on sequence data related to ITS 1, ITS 2 and ITS 1 + 5.8 s + ITS 2 of rDNA using maximum parsimony method and Bayesian inference have thrown light on species inter-relationship and evolution of Citrus species confirming our cytogenetical interpretations. The three true basic species i.e. Citrus medica, Citrus maxima and Citrus reticulata with their unique status have been resolved into distinct clades with molecular approaches as well. C. indica which occupies a unique position in the phylogenetic ladder of the genus Citrus has been resolved as a distinct clade and almost behaving as an out-group. The presences of quadrivalents in C. indica also echo and support its unique position. From our study it is amply

  15. 抗草甘膦转基因大豆对根际土壤氨氧化古菌群落多样性的影响%Effects of roundup ready transgenic soybean on ammonia-oxidizing archaeal diversity in rhizospheric soil

    Institute of Scientific and Technical Information of China (English)

    刘志华; 徐广惠; 王宏燕; 刘佳

    2012-01-01

    Roundup ready transgenic soybean [ Glycine max (L. ) Merr. ] (RRS) is one of the genetically modified crops and firstly commercialized by the Monsanto Company. In recent years, more attention has been paid on the risk assessment of RRS, including the potential effects on soil biota diversity. Ammonia-oxidizing archaea (AOA) are a group of the key microbes in nitrification, playing an important role in N cycle. By using PCR-DGGE cloning, this paper studied the diversity of AOA communities in the rhizosphere soils of RRS, its non-transgenic parental iso-line (RRS-S) , wild soybean (W-S) , and cultivated soybean (D-46) , aimed to provide theoretical basis for the ecological safety assessment on the transgenic soybean. The RRS had no remarkable effects on the AOA diversity, based on the Shannon diversity index and evenness index. The principal components analysis and DGGE analysis showed that the AOA community structure in the rhizosphere of RRS was significantly different with that in the rhizosphere of WS and D-46, but had no significant difference with that in the rhizosphere of RRS-S. Moreover, the AOA amok gene sequencing of DGGE bands and the phylogenetic analysis revealed that parts of the AOA in the rhizosphere of test soybean cultivars belonged to the clusters already reported in soil/ sediment, others belonged to the unknown clusters or groups in soil, but none of them belonged to the clusters in water or sediment. There was little change in the DGGE bands, among which,bands 1, 20, and 25 were missing, and band 3 was specific for RRS. In conclusion, RRS had no apparent effect on the diversity of AOA in rhizosphere soils, but could alter the composition of AOA community.%抗草甘膦转基因大豆是孟山都公司首次进行商业化生产的转基因作物.近年来其风险评价,包括土壤生物多样性风险评价受到越来越多的重视.氨氧化古菌是硝化过程的关键微生物,在氮素循环中起重要作用.本文

  16. Analysis of yeast and archaeal population dynamics in kimchi using denaturing gradient gel electrophoresis.

    Science.gov (United States)

    Chang, Ho-Won; Kim, Kyoung-Ho; Nam, Young-Do; Roh, Seong Woon; Kim, Min-Soo; Jeon, Che Ok; Oh, Hee-Mock; Bae, Jin-Woo

    2008-08-15

    Kimchi is a traditional Korean food that is fermented from vegetables such as Chinese cabbage and radish. Many bacteria are involved in kimchi fermentation and lactic acid bacteria are known to perform significant roles. Although kimchi fermentation presents a range of environmental conditions that could support many different archaea and yeasts, their molecular diversity within this process has not been studied. Here, we use PCR-denaturing gradient gel electrophoresis (DGGE) targeting the 16S and 26S rRNA genes, to characterize bacterial, archaeal and yeast dynamics during various types of kimchi fermentation. The DGGE analysis of archaea expressed a change of DGGE banding patterns during kimchi fermentation, however, no significant change was observed in the yeast DGGE banding patterns during kimchi fermentation. No significant difference was indicated in the archaeal DGGE profile among different types of kimchi. In the case of yeasts, the clusters linked to the manufacturing corporation. Haloarchaea such as Halococcus spp., Natronococcus spp., Natrialba spp. and Haloterrigena spp., were detected as the predominant archaea and Lodderomyces spp., Trichosporon spp., Candida spp., Saccharomyces spp., Pichia spp., Sporisorium spp. and Kluyveromyces spp. were the most common yeasts. PMID:18562030

  17. Archaeal Genome Guardians Give Insights into Eukaryotic DNA Replication and Damage Response Proteins

    Directory of Open Access Journals (Sweden)

    David S. Shin

    2014-01-01

    Full Text Available As the third domain of life, archaea, like the eukarya and bacteria, must have robust DNA replication and repair complexes to ensure genome fidelity. Archaea moreover display a breadth of unique habitats and characteristics, and structural biologists increasingly appreciate these features. As archaea include extremophiles that can withstand diverse environmental stresses, they provide fundamental systems for understanding enzymes and pathways critical to genome integrity and stress responses. Such archaeal extremophiles provide critical data on the periodic table for life as well as on the biochemical, geochemical, and physical limitations to adaptive strategies allowing organisms to thrive under environmental stress relevant to determining the boundaries for life as we know it. Specifically, archaeal enzyme structures have informed the architecture and mechanisms of key DNA repair proteins and complexes. With added abilities to temperature-trap flexible complexes and reveal core domains of transient and dynamic complexes, these structures provide insights into mechanisms of maintaining genome integrity despite extreme environmental stress. The DNA damage response protein structures noted in this review therefore inform the basis for genome integrity in the face of environmental stress, with implications for all domains of life as well as for biomanufacturing, astrobiology, and medicine.

  18. Advances in phylogenetic studies of Nematoda

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Nematoda is a metazoan group with extremely high diversity only next to Insecta. Caenorhabditis elegans is now a favorable experimental model animal in modern developmental biology, genetics and genomics studies. However, the phylogeny of Nematoda and the phylogenetic position of the phylum within animal kingdom have long been in debate. Recent molecular phylogenetic studies gave great challenges to the traditional nematode classification. The new phylogenies not only placed the Nematoda in the Ecdysozoan and divided the phylum into five clades, but also provided new insights into animal molecular identification and phylogenetic biodiversity studies. The present paper reviews major progress and remaining problems in the current molecular phylogenetic studies of Nematoda, and prospects the developmental tendencies of this field.

  19. TIPP: taxonomic identification and phylogenetic profiling

    Science.gov (United States)

    Nguyen, Nam-phuong; Mirarab, Siavash; Liu, Bo; Pop, Mihai; Warnow, Tandy

    2014-01-01

    Motivation: Abundance profiling (also called ‘phylogenetic profiling’) is a crucial step in understanding the diversity of a metagenomic sample, and one of the basic techniques used for this is taxonomic identification of the metagenomic reads. Results: We present taxon identification and phylogenetic profiling (TIPP), a new marker-based taxon identification and abundance profiling method. TIPP combines SAT\\'e-enabled phylogenetic placement a phylogenetic placement method, with statistical techniques to control the classification precision and recall, and results in improved abundance profiles. TIPP is highly accurate even in the presence of high indel errors and novel genomes, and matches or improves on previous approaches, including NBC, mOTU, PhymmBL, MetaPhyler and MetaPhlAn. Availability and implementation: Software and supplementary materials are available at http://www.cs.utexas.edu/users/phylo/software/sepp/tipp-submission/. Contact: warnow@illinois.edu Supplementary information: Supplementary data are available at Bioinformatics online. PMID:25359891

  20. A Note on Encodings of Phylogenetic Networks of Bounded Level

    CERN Document Server

    Gambette, Philippe

    2009-01-01

    Driven by the need for better models that allow one to shed light into the question how life's diversity has evolved, phylogenetic networks have now joined phylogenetic trees in the center of phylogenetics research. Like phylogenetic trees, such networks canonically induce collections of phylogenetic trees, clusters, and triplets, respectively. Thus it is not surprising that many network approaches aim to reconstruct a phylogenetic network from such collections. Related to the well-studied perfect phylogeny problem, the following question is of fundamental importance in this context: When does one of the above collections encode (i.e. uniquely describe) the network that induces it? In this note, we present a complete answer to this question for the special case of a level-1 (phylogenetic) network by characterizing those level-1 networks for which an encoding in terms of one (or equivalently all) of the above collections exists. Given that this type of network forms the first layer of the rich hierarchy of lev...

  1. High-resolution phylogenetic microbial community profiling

    Energy Technology Data Exchange (ETDEWEB)

    Singer, Esther; Coleman-Derr, Devin; Bowman, Brett; Schwientek, Patrick; Clum, Alicia; Copeland, Alex; Ciobanu, Doina; Cheng, Jan-Fang; Gies, Esther; Hallam, Steve; Tringe, Susannah; Woyke, Tanja

    2014-03-17

    The representation of bacterial and archaeal genome sequences is strongly biased towards cultivated organisms, which belong to merely four phylogenetic groups. Functional information and inter-phylum level relationships are still largely underexplored for candidate phyla, which are often referred to as microbial dark matter. Furthermore, a large portion of the 16S rRNA gene records in the GenBank database are labeled as environmental samples and unclassified, which is in part due to low read accuracy, potential chimeric sequences produced during PCR amplifications and the low resolution of short amplicons. In order to improve the phylogenetic classification of novel species and advance our knowledge of the ecosystem function of uncultivated microorganisms, high-throughput full length 16S rRNA gene sequencing methodologies with reduced biases are needed. We evaluated the performance of PacBio single-molecule real-time (SMRT) sequencing in high-resolution phylogenetic microbial community profiling. For this purpose, we compared PacBio and Illumina metagenomic shotgun and 16S rRNA gene sequencing of a mock community as well as of an environmental sample from Sakinaw Lake, British Columbia. Sakinaw Lake is known to contain a large age of microbial species from candidate phyla. Sequencing results show that community structure based on PacBio shotgun and 16S rRNA gene sequences is highly similar in both the mock and the environmental communities. Resolution power and community representation accuracy from SMRT sequencing data appeared to be independent of GC content of microbial genomes and was higher when compared to Illumina-based metagenome shotgun and 16S rRNA gene (iTag) sequences, e.g. full-length sequencing resolved all 23 OTUs in the mock community, while iTags did not resolve closely related species. SMRT sequencing hence offers various potential benefits when characterizing uncharted microbial communities.

  2. Familial relationships in hyperthermo- and acidophilic archaeal viruses

    DEFF Research Database (Denmark)

    Happonen, Lotta Johanna; Redder, Peter; Peng, Xu;

    2010-01-01

    Archaea often live in extreme, harsh environments such as acidic hot springs and hypersaline waters. To date, only two icosahedrally symmetric, membrane-containing archaeal viruses, SH1 and Sulfolobus turreted icosahedral virus (STIV), have been described in detail. We report the sequence and thr...

  3. A Survey of Protein Structures from Archaeal Viruses

    Directory of Open Access Journals (Sweden)

    Nikki Dellas

    2013-01-01

    Full Text Available Viruses that infect the third domain of life, Archaea, are a newly emerging field of interest. To date, all characterized archaeal viruses infect archaea that thrive in extreme conditions, such as halophilic, hyperthermophilic, and methanogenic environments. Viruses in general, especially those replicating in extreme environments, contain highly mosaic genomes with open reading frames (ORFs whose sequences are often dissimilar to all other known ORFs. It has been estimated that approximately 85% of virally encoded ORFs do not match known sequences in the nucleic acid databases, and this percentage is even higher for archaeal viruses (typically 90%–100%. This statistic suggests that either virus genomes represent a larger segment of sequence space and/or that viruses encode genes of novel fold and/or function. Because the overall three-dimensional fold of a protein evolves more slowly than its sequence, efforts have been geared toward structural characterization of proteins encoded by archaeal viruses in order to gain insight into their potential functions. In this short review, we provide multiple examples where structural characterization of archaeal viral proteins has indeed provided significant functional and evolutionary insight.

  4. Diversity of prokaryotes at a shallow submarine vent of Panarea Island (Italy by high-throughput sequencing

    Directory of Open Access Journals (Sweden)

    Teresa L. Maugeri

    2013-09-01

    Full Text Available To determine microbial community composition and possible key microbial processes in the shallow-sea hydrothermal vent system off Panarea Island (Italy, we examined bacterial and archaeal communities of sediment and fluid samples from a hot vent by 16S rDNA Illumina sequencing technique. Both high abundant (>1% of total sequences, low abundant (from 0.1 to <1% and rare (< 0.1% phylogenetic groups were responsible for the distinct prokaryotic communities characterizing the heated sediment and fluid. The bacterial and archaeal communities from sediment were dominated by sequences affiliated with Rhodovulum genus (Alphaproteobacteria, including phototrophic ferrous-iron-oxidizing purple bacteria, Thiohalospira and Thiomicrospira (Gammaproteobacteria, typically involved in the sulphur cycle, and Methanococcus (Euryarchaeota. Fluid communities were dominated by anoxygenic phototrophic members of Chlorobium, followed by Thiomicrospira (Gammaproteobacteria, Sulfurimonas, Arcobacter and Sulfurospirillum (Epsilonproteobacteria, and Methanosarcina (Euryarchaeota. Obtained sequences were affiliated with prokaryotes taking a key part in the carbon, iron and sulphur cycling at the shallow hydrothermal system off Panarea Island. Despite the huge sequencing efforts, a great number of Bacteria and Archaea still remains unaffiliated at genus level, indicating that Black Point vent represents a hotspot of prokaryotic diversity.

  5. Archaeal and bacterial communities in three alkaline hot springs in Heart Lake Geyser Basin, Yellowstone National Park

    Science.gov (United States)

    Bowen De León, Kara; Gerlach, Robin; Peyton, Brent M.; Fields, Matthew W.

    2013-01-01

    The Heart Lake Geyser Basin (HLGB) is remotely located at the base of Mount Sheridan in southern Yellowstone National Park (YNP), Wyoming, USA and is situated along Witch Creek and the northwestern shore of Heart Lake. Likely because of its location, little is known about the microbial community structure of springs in the HLGB. Bacterial and archaeal populations were monitored via small subunit (SSU) rRNA gene pyrosequencing over 3 years in 3 alkaline (pH 8.5) hot springs with varying temperatures (44°C, 63°C, 75°C). The bacterial populations were generally stable over time, but varied by temperature. The dominant bacterial community changed from moderately thermophilic and photosynthetic members (Cyanobacteria and Chloroflexi) at 44°C to a mixed photosynthetic and thermophilic community (Deinococcus-Thermus) at 63°C and a non-photosynthetic thermophilic community at 75°C. The archaeal community was more variable across time and was predominantly a methanogenic community in the 44 and 63°C springs and a thermophilic community in the 75°C spring. The 75°C spring demonstrated large shifts in the archaeal populations and was predominantly Candidatus Nitrosocaldus, an ammonia-oxidizing crenarchaeote, in the 2007 sample, and almost exclusively Thermofilum or Candidatus Caldiarchaeum in the 2009 sample, depending on SSU rRNA gene region examined. The majority of sequences were dissimilar (≥10% different) to any known organisms suggesting that HLGB possesses numerous new phylogenetic groups that warrant cultivation efforts. PMID:24282404

  6. Archaeal and bacterial communities in three alkaline hot springs in Heart Lake Geyser Basin, Yellowstone National Park

    Directory of Open Access Journals (Sweden)

    Kara Bowen De León

    2013-11-01

    Full Text Available The Heart Lake Geyser Basin (HLGB is remotely located at the base of Mount Sheridan in southern Yellowstone National Park, Wyoming, USA and is situated along Witch Creek and the northwestern shore of Heart Lake. Likely because of its location, little is known about the microbial community structure of springs in the HLGB. Bacterial and archaeal populations were monitored via small subunit (SSU rRNA gene pyrosequencing over 3 years in 3 alkaline (pH 8.5 hot springs with varying temperatures (44°C, 63°C, 75°C. The bacterial populations were generally stable over time, but varied by temperature. The dominant bacterial community changed from moderately thermophilic and photosynthetic members (Cyanobacteria and Chloroflexi at 44°C to a mixed photosynthetic and thermophilic community (Deinococcus-Thermus at 63°C and a non-photosynthetic thermophilic community at 75°C. The archaeal community was more variable across time and was predominantly a methanogenic community in the 44°C and 63°C springs and a hyperthermophilic community in the 75°C spring. The 75°C spring demonstrated large shifts in the archaeal populations and was predominantly Candidatus Nitrosocaldus, an ammonia-oxidizing crenarchaeote, in the 2007 sample, and almost exclusively Thermofilum or Candidatus Caldiarchaeum in the 2009 sample, depending on SSU rRNA gene region examined. The majority of sequences were dissimilar (≥10% different to any known organisms suggesting that HLGB possesses numerous new phylogenetic groups that warrant cultivation efforts.

  7. Asperisporium and Pantospora (Mycosphaerellaceae): epitypifications and phylogenetic placement

    NARCIS (Netherlands)

    Minnis, A.M.; Kennedy, A.H.; Grenier, D.B.; Rehner, S.A.; Bischoff, J.F.

    2012-01-01

    The species-rich family Mycosphaerellaceae contains considerable morphological diversity and includes numerous anamorphic genera, many of which are economically important plant pathogens. Recent revisions and phylogenetic research have resulted in taxonomic instability. Ameliorating this problem req

  8. 生姜种质遗传多样性和亲缘关系的SRAP分析%Genetic Diversity and Phylogenetic Relationship of Ginger Germplasm Resources Revealed by SRAPs

    Institute of Scientific and Technical Information of China (English)

    李秀; 徐坤; 巩彪

    2014-01-01

    [Objective]Ginger is vegetatively asexual crop that owns lots of local varieties, and its biological characteristics have been verified in many aspects caused by climate change, natural and artificial selection for thousands of years. This study was conducted to make a scientific classification of ginger germplasm, provide evidence for germplasm collection, protection and innovation of ginger by investigating the genetic diversity and relationship.[Method]Good genomic DNA was extracted from young leaves of 51 ginger accessions from different areas of the world following the CTAB method, and then were amplified by sequence-related amplified polymorphism molecular markers to analyze genetic diversity and phylogenetic relationship. Separation of the amplified fragments was performed on 6% denaturing polyacrylamide gels, The gels were stained with AgNO 3 for visualizing the SRAP fragments, and then“0, 1”matrix was obtained according to the electrophoresis results. The number of polymorphic loci, percentage of polymorphic loci, effective number of alleles, Nei’s genetic similarity coefficient, genetic distance and the indexes of Nei’s genetic diversity and Shannon information were estimated by POPGENE version1.32. The cluster analysis of 51 ginger accessions based on unweighted pair-group method and 7 ginger populations based on Nei’s genetic distance were performed on NTSYS version2.10e to classify the ginger germplasm. Meanwhile, the origin and transmission of ginger were discussed in accordance with genetic diversity and phylogenetic relationship of ginger germplasm in different ecotopes and in light of the relevant characteristics of origin center and historical records.[Result]Among the 305 bands detected by 15 selective primer pairs, 188 (61.68%) were polymorphic. On average, each primer combination amplified 20.33 loci and 12.53 polymorphic loci. This showed that genetic variation of ginger is extensive. The average indexes of Nei’s genetic diversity

  9. Archaeal communities of Arctic methane-containing permafrost.

    Science.gov (United States)

    Shcherbakova, Victoria; Yoshimura, Yoshitaka; Ryzhmanova, Yana; Taguchi, Yukihiro; Segawa, Takahiro; Oshurkova, Victoria; Rivkina, Elizaveta

    2016-10-01

    In the present study, we used culture-independent methods to investigate the diversity of methanogenic archaea and their distribution in five permafrost samples collected from a borehole in the Kolyma River Lowland (north-east of Russia). Total DNA was extracted from methane-containing permafrost samples of different age and amplified by PCR. The resulting DNA fragments were cloned. Phylogenetic analysis of the sequences showed the presence of archaea in all studied samples; 60%-95% of sequences belonged to the Euryarchaeota. Methanogenic archaea were novel representatives of Methanosarcinales, Methanomicrobiales, Methanobacteriales and Methanocellales orders. Bathyarchaeota (Miscellaneous Crenarchaeota Group) representatives were found among nonmethanogenic archaea in all the samples studied. The Thaumarchaeota representatives were not found in the upper sample, whereas Woesearchaeota (formerly DHVEG-6) were found in the three deepest samples. Unexpectedly, the greatest diversity of archaea was observed at a depth of 22.3 m, probably due to the availability of the labile organic carbon and/or due to the migration of the microbial cells during the freezing front towards the bottom. PMID:27312964

  10. Ugan古河道胡杨可培养内生细菌的多样性%Phylogenetic diversity of culturable endophytic bacteria Isolated from the Populus euphratica at the disused ancient Ugan River

    Institute of Scientific and Technical Information of China (English)

    卡依尔·玉素甫; 谢仁娜依·甫拉提; 玛丽帕·吐达洪1; 马丽艳木·阿木东; 艾尼江·尔斯曼; 祖母拉提·阿布都热依木; 艾尔肯·热合曼

    2011-01-01

    [目的[为了了解塔河废弃古河道胡杨可培养内生细菌的多样性.[方法[从2棵胡杨树干部抽出其内存液,采用3种不同的培养基对样品的内生细菌进行了分离纯化;对它们进行16S rDNA测定和系统进化分析.[结果[分离纯化不同表型的细菌62株,对它们的16s rDNA序列分析表明,62株菌分别属于4个大类群;厚壁菌门(Firmicutes)、放线菌门(Actinobacteria)、α-变形菌纲(Alpha Proteobacteria)、γ-变形菌纲(GammaProteobacteria),18个属,32个种;芽孢杆菌属和假单胞菌属是胡杨可培养内生细菌的优势细菌种群,它们分别占已测种群的40.32%、16.13%.其中菌株KTH-63为葡萄球菌科的潜在的新属新种,它与最近源菌株的16s rDNA序列相似率为92.491%;9株菌KLH.21、KLH-1、KTH-8、KTH-14、KNA-26、KLH-18、KTH-20、KNA-3、KLH-25是潜在的新种(16S rDNA相似率为96.089%-97.769%),胡杨树干内存液中潜在新种的发现率高达总分离检测菌株的16.13%.本研究获得的胡杨可培养内生细菌的群落结构数据给植物内生细菌新增了10个属,18个种.[结论[胡杨具有多样性极其丰富的可培养内生细菌菌种资源,土著新种的发现频率超出了预期,胡杨可培养内生细菌的群落结构极大地刷新了植物内生细菌的种群记录,极具进一步发掘的潜力.%[Objective]The aim of this study was to identify the culturable endophytic bacteria recovered from the Populus euphratica at the disused (122 years ago) ancient Ugan river of middle reachs of Tarim river, and to understand their Phylogenetic diversity and community structure.[Methods]Bacteria were isolated from the storage liquid in the stem of 2 Populus euphratica stands by using 3 types of different cultural medium ( Luria -Bertani,Trypticase Soy Agar and Nutrient Agar) , followed carry out 16S rDNA identifications and analysis of their biodiversity.[Results]A total of 62 phenotypically different isolates were sequenced and

  11. Abundance and diversity of ammonia-oxidizing archaea and bacteria on granular activated carbon and their fates during drinking water purification process.

    Science.gov (United States)

    Niu, Jia; Kasuga, Ikuro; Kurisu, Futoshi; Furumai, Hiroaki; Shigeeda, Takaaki; Takahashi, Kazuhiko

    2016-01-01

    Ammonia is a precursor to trichloramine, which causes an undesirable chlorinous odor. Granular activated carbon (GAC) filtration is used to biologically oxidize ammonia during drinking water purification; however, little information is available regarding the abundance and diversity of ammonia-oxidizing archaea (AOA) and bacteria (AOB) associated with GAC. In addition, their sources and fates in water purification process remain unknown. In this study, six GAC samples were collected from five full-scale drinking water purification plants in Tokyo during summer and winter, and the abundance and community structure of AOA and AOB associated with GAC were studied in these two seasons. In summer, archaeal and bacterial amoA genes on GACs were present at 3.7 × 10(5)-3.9 × 10(8) gene copies/g-dry and 4.5 × 10(6)-4.2 × 10(8) gene copies/g-dry, respectively. In winter, archaeal amoA genes remained at the same level, while bacterial amoA genes decreased significantly for all GACs. No differences were observed in the community diversity of AOA and AOB from summer to winter. Phylogenetic analysis revealed high AOA diversity in group I.1a and group I.1b in raw water. Terminal-restriction fragment length polymorphism analysis of processed water samples revealed that AOA diversity decreased dramatically to only two OTUs in group I.1a after ozonation, which were identical to those detected on GAC. It suggests that ozonation plays an important role in determining AOA diversity on GAC. Further study on the cell-specific activity of AOA and AOB is necessary to understand their contributions to in situ nitrification performance. PMID:26463999

  12. Bacterial and archaeal resistance to ionizing radiation

    Science.gov (United States)

    Confalonieri, F.; Sommer, S.

    2011-01-01

    Organisms living in extreme environments must cope with large fluctuations of temperature, high levels of radiation and/or desiccation, conditions that can induce DNA damage ranging from base modifications to DNA double-strand breaks. The bacterium Deinococcus radiodurans is known for its resistance to extremely high doses of ionizing radiation and for its ability to reconstruct a functional genome from hundreds of radiation-induced chromosomal fragments. Recently, extreme ionizing radiation resistance was also generated by directed evolution of an apparently radiation-sensitive bacterial species, Escherichia coli. Radioresistant organisms are not only found among the Eubacteria but also among the Archaea that represent the third kingdom of life. They present a set of particular features that differentiate them from the Eubacteria and eukaryotes. Moreover, Archaea are often isolated from extreme environments where they live under severe conditions of temperature, pressure, pH, salts or toxic compounds that are lethal for the large majority of living organisms. Thus, Archaea offer the opportunity to understand how cells are able to cope with such harsh conditions. Among them, the halophilic archaeon Halobacterium sp and several Pyrococcus or Thermococcus species, such as Thermococcus gammatolerans, were also shown to display high level of radiation resistance. The dispersion, in the phylogenetic tree, of radioresistant prokaryotes suggests that they have independently acquired radioresistance. Different strategies were selected during evolution including several mechanisms of radiation byproduct detoxification and subtle cellular metabolism modifications to help cells recover from radiation-induced injuries, protection of proteins against oxidation, an efficient DNA repair tool box, an original pathway of DNA double-strand break repair, a condensed nucleoid that may prevent the dispersion of the DNA fragments and specific radiation-induced proteins involved in

  13. Bacterial and archaeal resistance to ionizing radiation

    International Nuclear Information System (INIS)

    Organisms living in extreme environments must cope with large fluctuations of temperature, high levels of radiation and/or desiccation, conditions that can induce DNA damage ranging from base modifications to DNA double-strand breaks. The bacterium Deinococcus radiodurans is known for its resistance to extremely high doses of ionizing radiation and for its ability to reconstruct a functional genome from hundreds of radiation-induced chromosomal fragments. Recently, extreme ionizing radiation resistance was also generated by directed evolution of an apparently radiation-sensitive bacterial species, Escherichia coli. Radioresistant organisms are not only found among the Eubacteria but also among the Archaea that represent the third kingdom of life. They present a set of particular features that differentiate them from the Eubacteria and eukaryotes. Moreover, Archaea are often isolated from extreme environments where they live under severe conditions of temperature, pressure, pH, salts or toxic compounds that are lethal for the large majority of living organisms. Thus, Archaea offer the opportunity to understand how cells are able to cope with such harsh conditions. Among them, the halophilic archaeon Halobacterium sp and several Pyrococcus or Thermococcus species, such as Thermococcus gammatolerans, were also shown to display high level of radiation resistance. The dispersion, in the phylogenetic tree, of radioresistant prokaryotes suggests that they have independently acquired radioresistance. Different strategies were selected during evolution including several mechanisms of radiation byproduct detoxification and subtle cellular metabolism modifications to help cells recover from radiation-induced injuries, protection of proteins against oxidation, an efficient DNA repair tool box, an original pathway of DNA double-strand break repair, a condensed nucleoid that may prevent the dispersion of the DNA fragments and specific radiation-induced proteins involved in

  14. A shift in the archaeal nitrifier community in response to natural and anthropogenic disturbances in the northern Gulf of Mexico.

    Science.gov (United States)

    Newell, Silvia E; Eveillard, Damien; McCarthy, Mark J; Gardner, Wayne S; Liu, Zhanfei; Ward, Bess B

    2014-02-01

    The Gulf of Mexico is affected by hurricanes and suffers seasonal hypoxia. The Deepwater Horizon oil spill impacted every trophic level in the coastal region. Despite their importance in bioremediation and biogeochemical cycles, it is difficult to predict the responses of microbial communities to physical and anthropogenic disturbances. Here, we quantify sediment ammonia-oxidizing archaeal (AOA) community diversity, resistance and resilience, and important geochemical factors after major hurricanes and the oil spill. Dominant AOA archetypes correlated with different geochemical factors, suggesting that different AOA are constrained by distinct parameters. Diversity was lowest after the hurricanes, showing weak resistance to physical disturbances. However, diversity was highest during the oil spill and coincided with a community shift, suggesting a new alternative stable state sustained for at least 1 year. The new AOA community was not significantly different from that at the spill site 1 year after the spill. This sustained shift in nitrifier community structure may be a result of oil exposure. PMID:24596268

  15. A comparative study of microbial diversity and community structure in marine sediments using poly(A tailing and reverse transcription PCR

    Directory of Open Access Journals (Sweden)

    Tatsuhiko eHoshino

    2013-06-01

    Full Text Available To obtain a better understanding of metabolically active microbial communities, we tested a molecular ecological approach using poly(A tailing of environmental 16S rRNA, followed by full-length complementary DNA (cDNA synthesis and sequencing to eliminate potential biases caused by mismatching of PCR primer sequences. The RNA pool tested was extracted from marine sediments of the Yonaguni Knoll IV hydrothermal field in the southern Okinawa Trough. The sequences obtained using the ploy(A tailing method were compared statistically and phylogenetically with those obtained using conventional reverse transcription-polymerase chain reaction (RT-PCR with published domain-specific primers. Both methods indicated that Deltaproteobacteria are predominant in sediment (>85% of the total sequence read. The poly(A tailing method indicated that Desulfobacterales were the predominant deltaproteobacteria, while most of the sequences in libraries constructed using RT-PCR were derived from Desulfuromonadales. This discrepancy may have been due to low coverage of Desulfobacterales by the primers used. A comparison of library diversity indices indicated that the poly(A tailing method retrieves more phylogenetically diverse sequences from the environment. The four archaeal 16S rRNA sequences that were obtained using the poly(A tailing method formed deeply branching lineages that were related to Candidatus Parvarchaeum and the Ancient Archaeal Group. These results clearly demonstrate that poly(A tailing followed by cDNA sequencing is a powerful and less biased molecular ecological approach for the study of metabolically active microbial communities.

  16. Controls on bacterial and archaeal community structure and greenhouse gas production in natural, mined, and restored Canadian peatlands

    Directory of Open Access Journals (Sweden)

    Nathan eBasiliko

    2013-07-01

    Full Text Available Northern peatlands are important global C reservoirs, largely because of their slow rates of microbial C mineralization. Particularly in sites that are heavily influenced by anthropogenic disturbances, there is scant information about microbial ecology and whether or not microbial community structure influences greenhouse gas production. This work characterized communities of bacteria and archaea using terminal restriction fragment length polymorphism and sequence analysis of 16S rRNA and functional genes across eight natural, mined, or restored peatlands in two locations in eastern Canada. Correlations were explored among chemical properties of peat, bacterial and archaeal community structure, and carbon dioxide and methane production rates under oxic and anoxic conditions. Bacteria and archaea similar to those found in other peat soil environments were detected. In contrast to other reports, methanogen diversity was low in our study, with only 2 groups of known or suspected methanogens. Although mining and restoration affected substrate availability and microbial activity, these land-uses did not consistently affect bacterial or archaeal community composition. In fact, larger differences were observed between the two locations and between oxic and anoxic peat samples than between mined and restored sites, with anoxic samples characterized by less detectable bacterial diversity and stronger dominance by members of the phylum Acidobacteria. There were also no apparent strong linkages between prokaryote community structure and methane or carbon dioxide production, suggesting that different organisms exhibit functional redundancy and/or that the same taxa function at very different rates when exposed to different peat substrates. In contrast to other earlier work focusing on fungal communities across similar mined and restored peatlands, bacterial and archaeal communities appeared to be more resistant or resilient to peat substrate changes brought

  17. Distribution of Archaeal and Bacterial communities in a subtropical reservoir

    Directory of Open Access Journals (Sweden)

    Laís Américo Soares

    2015-12-01

    Full Text Available Abstract Aim: Microbial communities play a central role in environmental process such as organic matter mineralization and the nutrient cycling process in aquatic ecosystems. Despite their ecological importance, variability of the structure of archaeal and bacterial communities in freshwater remains understudied. Methods In the present study we investigated the richness and density of archaea and bacteria in the water column and sediments of the Itupararanga Reservoir. We also evaluated the relationship between the communities and the biotic and abiotic characteristics. Samples were taken at five depths in the water column next to the dam and three depths next to the reservoir entrance. Results PCR-DGGE evaluation of the archaeal and bacterial communities showed that both were present in the water column, even in oxygenated conditions. Conclusions The density of the bacteria (qPCR was greater than that of the archaea, a result of the higher metabolic plasticity of bacteria compared with archaea.

  18. The influence of different land uses on the structure of archaeal communities in Amazonian anthrosols based on 16S rRNA and amoA genes.

    Science.gov (United States)

    Taketani, Rodrigo Gouvêa; Tsai, Siu Mui

    2010-05-01

    Soil from the Amazonian region is usually regarded as unsuitable for agriculture because of its low organic matter content and low pH; however, this region also contains extremely rich soil, the Terra Preta Anthrosol. A diverse archaeal community usually inhabits acidic soils, such as those found in the Amazon. Therefore, we hypothesized that this community should be sensitive to changes in the environment. Here, the archaeal community composition of Terra Preta and adjacent soil was examined in four different sites in the Brazilian Amazon under different anthropic activities. The canonical correspondence analysis of terminal restriction fragment length polymorphisms has shown that the archaeal community structure was mostly influenced by soil attributes that differentiate the Terra Preta from the adjacent soil (i.e., pH, sulfur, and organic matter). Archaeal 16S rRNA gene clone libraries indicated that the two most abundant genera in both soils were Candidatus nitrosphaera and Canditatus nitrosocaldus. An ammonia monoxygenase gene (amoA) clone library analysis indicated that, within each site, there was no significant difference between the clone libraries of Terra Preta and adjacent soils. However, these clone libraries indicated there were significant differences between sites. Quantitative PCR has shown that Terra Preta soils subjected to agriculture displayed a higher number of amoA gene copy numbers than in adjacent soils. On the other hand, soils that were not subjected to agriculture did not display significant differences on amoA gene copy numbers between Terra Preta and adjacent soils. Taken together, our findings indicate that the overall archaeal community structure in these Amazonian soils is determined by the soil type and the current land use. PMID:20204349

  19. Phylogenetic effective sample size

    OpenAIRE

    Bartoszek, Krzysztof

    2015-01-01

    In this paper I address the question - how large is a phylogenetic sample I propose a definition of a phylogenetic effective sample size for Brownian motion and Ornstein-Uhlenbeck processes - the regression effective sample size. I discuss how mutual information can be used to define an effective sample size in the non-normal process case and compare these two definitions to an already present concept of effective sample size (the mean effective sample size). Through a simulation study I find...

  20. Archaeal promoter architecture and mechanism of gene activation

    DEFF Research Database (Denmark)

    Peng, Nan; Ao, Xiang; Liang, Yun Xiang;

    2011-01-01

    Sulfolobus solfataricus and Sulfolobus islandicus contain several genes exhibiting D-arabinose-inducible expression and these systems are ideal for studying mechanisms of archaeal gene expression. At sequence level, only two highly conserved cis elements are present on the promoters: a regulatory...... mechanisms include TFB (transcription factor B) recruitment by the ara-box-binding factor to activate gene expression and modulation of TFB recruitment efficiency to yield differential gene expression....

  1. TBP domain symmetry in basal and activated archaeal transcription.

    Science.gov (United States)

    Ouhammouch, Mohamed; Hausner, Winfried; Geiduschek, E Peter

    2009-01-01

    The TATA box binding protein (TBP) is the platform for assembly of archaeal and eukaryotic transcription preinitiation complexes. Ancestral gene duplication and fusion events have produced the saddle-shaped TBP molecule, with its two direct-repeat subdomains and pseudo-two-fold symmetry. Collectively, eukaryotic TBPs have diverged from their present-day archaeal counterparts, which remain highly symmetrical. The similarity of the N- and C-halves of archaeal TBPs is especially pronounced in the Methanococcales and Thermoplasmatales, including complete conservation of their N- and C-terminal stirrups; along with helix H'1, the C-terminal stirrup of TBP forms the main interface with TFB/TFIIB. Here, we show that, in stark contrast to its eukaryotic counterparts, multiple substitutions in the C-terminal stirrup of Methanocaldococcus jannaschii (Mja) TBP do not completely abrogate basal transcription. Using DNA affinity cleavage, we show that, by assembling TFB through its conserved N-terminal stirrup, Mja TBP is in effect ambidextrous with regard to basal transcription. In contrast, substitutions in either its N- or the C-terminal stirrup abrogate activated transcription in response to the Lrp-family transcriptional activator Ptr2. PMID:19007415

  2. Ribonucleoproteins in Archaeal Pre-rRNA Processing and Modification

    Directory of Open Access Journals (Sweden)

    W. S. Vincent Yip

    2013-01-01

    Full Text Available Given that ribosomes are one of the most important cellular macromolecular machines, it is not surprising that there is intensive research in ribosome biogenesis. Ribosome biogenesis is a complex process. The maturation of ribosomal RNAs (rRNAs requires not only the precise cleaving and folding of the pre-rRNA but also extensive nucleotide modifications. At the heart of the processing and modifications of pre-rRNAs in Archaea and Eukarya are ribonucleoprotein (RNP machines. They are called small RNPs (sRNPs, in Archaea, and small nucleolar RNPs (snoRNPs, in Eukarya. Studies on ribosome biogenesis originally focused on eukaryotic systems. However, recent studies on archaeal sRNPs have provided important insights into the functions of these RNPs. This paper will introduce archaeal rRNA gene organization and pre-rRNA processing, with a particular focus on the discovery of the archaeal sRNP components, their functions in nucleotide modification, and their structures.

  3. Structure and Evolution of the Archaeal Lipid Synthesis Enzyme sn-Glycerol-1-phosphate Dehydrogenase.

    Science.gov (United States)

    Carbone, Vincenzo; Schofield, Linley R; Zhang, Yanli; Sang, Carrie; Dey, Debjit; Hannus, Ingegerd M; Martin, William F; Sutherland-Smith, Andrew J; Ronimus, Ron S

    2015-08-28

    One of the most critical events in the origins of cellular life was the development of lipid membranes. Archaea use isoprenoid chains linked via ether bonds to sn-glycerol 1-phosphate (G1P), whereas bacteria and eukaryotes use fatty acids attached via ester bonds to enantiomeric sn-glycerol 3-phosphate. NAD(P)H-dependent G1P dehydrogenase (G1PDH) forms G1P and has been proposed to have played a crucial role in the speciation of the Archaea. We present here, to our knowledge, the first structures of archaeal G1PDH from the hyperthermophilic methanogen Methanocaldococcus jannaschii with bound substrate dihydroxyacetone phosphate, product G1P, NADPH, and Zn(2+) cofactor. We also biochemically characterized the enzyme with respect to pH optimum, cation specificity, and kinetic parameters for dihydroxyacetone phosphate and NAD(P)H. The structures provide key evidence for the reaction mechanism in the stereospecific addition for the NAD(P)H-based pro-R hydrogen transfer and the coordination of the Zn(2+) cofactor during catalysis. Structure-based phylogenetic analyses also provide insight into the origins of G1PDH. PMID:26175150

  4. Microbial diversity of a Brazilian coastal region influenced by an upwelling system and anthropogenic activity.

    Directory of Open Access Journals (Sweden)

    Juliano C Cury

    Full Text Available BACKGROUND: Upwelling systems are characterised by an intense primary biomass production in the surface (warmest water after the outcrop of the bottom (coldest water, which is rich in nutrients. Although it is known that the microbial assemblage plays an important role in the food chain of marine systems and that the upwelling systems that occur in southwest Brazil drive the complex dynamics of the food chain, little is known about the microbial composition present in this region. METHODOLOGY/PRINCIPAL FINDINGS: We carried out a molecular survey based on SSU rRNA gene from the three domains of the phylogenetic tree of life present in a tropical upwelling region (Arraial do Cabo, Rio de Janeiro, Brazil. The aim was to analyse the horizontal and vertical variations of the microbial composition in two geographically close areas influenced by anthropogenic activity (sewage disposal/port activity and upwelling phenomena, respectively. A lower estimated diversity of microorganisms of the three domains of the phylogenetic tree of life was found in the water of the area influenced by anthropogenic activity compared to the area influenced by upwelling phenomena. We observed a heterogenic distribution of the relative abundance of taxonomic groups, especially in the Archaea and Eukarya domains. The bacterial community was dominated by Proteobacteria, Cyanobacteria and Bacteroidetes phyla, whereas the microeukaryotic community was dominated by Metazoa, Fungi, Alveolata and Stramenopile. The estimated archaeal diversity was the lowest of the three domains and was dominated by uncharacterised marine Crenarchaeota that were most closely related to Marine Group I. CONCLUSIONS/SIGNIFICANCE: The variety of conditions and the presence of different microbial assemblages indicated that the area of Arraial do Cabo can be used as a model for detailed studies that contemplate the correlation between pollution-indicating parameters and the depletion of microbial

  5. [Prokaryotic microbial diversity of the ancient salt deposits in the Kunming Salt Mine, P.R. China].

    Science.gov (United States)

    Xiao, Wei; Peng, Qian; Liu, Hong-wei; Wen, Meng-liang; Cui, Xiao-long; Yang, Ya-ling; Duan, Dong-cheng; Chen, Wei; Deng, Lan; Li, Qin-yuan; Chen, Yi-guang; Wang, Zhi-gang; Ren, Zhen; Liu, Ji-hui

    2007-04-01

    The prokaryotic microbial diversity of the ancient salt deposits in the Kunming Salt Mine, PR China was investigated using PCR-DGGE and rRNA approaches. Total community DNA was extracted and purified by a direct method, which yielded amplified DNA of high molecular weight for samples. A variable region of 16S rRNA gene was then amplified by PCR with bacterial and archaeal primers and analyzed by denaturing gradient gel electrophoresis (DGGE). Twenty-seven major bands were detected in the bacterial DGGE profile of the sample, but only one band of pure culture strains of bacteria isolated from the Kunming Salt Mine matched with one band of sample. No band of pure culture strains of archaea isolated from the Kunming Salt Mine matched with 18 major bands of sample. The results indicated that most of microbes in this environment are likely uncultivable. Clones on the plate were not the predominant species in the community. Two 16S rRNA gene clone libraries (bacteria and archaea) were also constructed, and 36 and 20 clones were selected for amplified ribosomal DNA restriction analysis (ARDRA). ARDRA with enzymes Afa I, Hha I, Hae III revealed 10 bacterial operational taxonomic units (OTUs), with three most abundant OTUs accounting for 38.9%, 25.0%, 16.7% of all the bacterial 16S rDNA clones, respectively. The remaining 7 OTUs presented at low levels, were represented by a single clone. Eight archaeal OTUs were obtained but no predominant OTUs. Some clones were sequenced and each sequence was compared with all nucleotide sequences in GenBank database. Examination of 16S rDNA clones showed that the ancient salt deposits in the Kunming Salt Mine contained a phylogenetically diverse population of organisms from the Bacteria domain with members of three major lineages represented: alpha-proteobacteria, gamma-Proteobacteria and Actinobacteria, especially Pseudomonas. Surprisingly, we recovered a variety of sequence closely related to Actinobacteria which was not found in other

  6. Yeast-Derived β-1,3-Glucan Substrate Significantly Increased the Diversity of Methanogens DuringIn vitro Fermentation of Porcine Colonic Digesta

    Institute of Scientific and Technical Information of China (English)

    LUO Yu-heng; LI Hua; LUO Jun-qiu; ZHANG Ke-ying

    2013-01-01

    Theβ-1,3-glucan from yeast has been extensively examined for its immuno-enhancing effects in animals. However, investigation on the relationship amongβ-glucan, gut microbiota and immune-modulating effects remains limited particularly in pigs. Considering the critical roles of gut methanogens in the microbial fermentation, energy metabolism and disease resistance, we investigated the phylogenetic diversity of methanogens from fermented cultures of porcine colonic digesta with (G) or without (N) yeastβ-glucan based on sequences of the archaeal 16S rRNA gene. A total of 145 sequences in the G library were assigned into 8 operational taxonomic units (OTUs) with the majority of sequences (114/145) related to strainsMethanobrevibactermillerae orMethanobrevibactergottschalkii with high identities ranging from 97.9 to 98.6%, followed by 23 sequences toMethanobrevibacter ruminantium, 2 sequences toMethanobrevibactersmithii and one sequence toMethanobrevibacter wolinii. The 142 sequences in the N library were assigned to 2 OTUs with most sequences (127/142) related to strainsM.millerae orM.gottschalkii with sequence identities ranging from 97.9 to 98.5%, and 15 sequences related toM.gottschalkiiwith 97.9% identity. Shannon diversity index showed that the G library exhibited signiifcantly higher archaeal diversity (P<0.05) and Libshuff analysis indicated the differences in the community structure between the two libraries were signiifcant (P<0.0001). In conclusion, the current study provides evidence that addition of yeast β-glucan signiifcantly increased the diversity of methanogens inin vitro fermented porcine colonic digesta.

  7. Abundance and diversity of ammonia-oxidizing archaea and bacteria in sediments of trophic end members of the Laurentian Great Lakes, Erie and Superior.

    Directory of Open Access Journals (Sweden)

    Annette Bollmann

    Full Text Available Ammonia oxidation is the first step of nitrification carried out by ammonia-oxidizing Archaea (AOA and Bacteria (AOB. Lake Superior and Erie are part of the Great Lakes system differing in trophic status with Lake Superior being oligotrophic and Lake Erie meso- to eutrophic. Sediment samples were collected from both lakes and used to characterize abundance and diversity of AOA and AOB based on the ammonia monooxygenase (amoA gene. Diversity was accessed by a pyro-sequencing approach and the obtained sequences were used to determine the phylogeny and alpha and beta diversity of the AOA and AOB populations. In Lake Erie copy numbers of bacterial amoA genes were in the same order of magnitude or even higher than the copy numbers of the archaeal amoA genes, while in Lake Superior up to 4 orders of magnitude more archaeal than bacterial amoA copies were detected. The AOB detected in the samples from Lake Erie belonged to AOB that are frequently detected in freshwater. Differences were detected between the phylogenetic affiliations of the AOA from the two lakes. Most sequences detected in Lake Erie clustered in the Nitrososphaera cluster (Thaumarchaeal soil group I.1b where as most of the sequences in Lake Superior were found in the Nitrosopumilus cluster (Thaumarchaeal marine group I.1a and the Nitrosotalea cluster. Pearson correlations and canonical correspondence analysis (CCA showed that the differences in abundance and diversity of AOA are very likely related to the sampling location and thereby to the different trophic states of the lakes.

  8. Microbial community structure analysis of a benzoate-degrading halophilic archaeal enrichment.

    Science.gov (United States)

    Dalvi, Sonal; Youssef, Noha H; Fathepure, Babu Z

    2016-05-01

    A benzoate-degrading archaeal enrichment was developed using sediment samples from Rozel Point at Great Salt Lake, UT. The enrichment degraded benzoate as the sole carbon source at salinity ranging from 2.0 to 5.0 M NaCl with highest rate of degradation observed at 4.0 M. The enrichment was also tested for its ability to grow on other aromatic compounds such as 4-hydroxybenzoic acid (4-HBA), gentisic acid, protocatechuic acid (PCA), catechol, benzene and toluene as the sole sources of carbon and energy. Of these, the culture only utilized 4-HBA as the carbon source. To determine the initial steps in benzoate degradation pathway, a survey of ring-oxidizing and ring-cleaving genes was performed using degenerate PCR primers. Results showed the presence of 4-hydroxybenzoate 3-monooxygenase (4-HBMO) and protocatechuate 3, 4-dioxygenase (3,4-PCA) genes suggesting that the archaeal enrichment might degrade benzoate to 4-HBA that is further converted to PCA by 4-HBMO and, thus, formed PCA would undergo ring-cleavage by 3,4-PCA to form intermediates that enter the Krebs cycle. Small subunit rRNA gene-based diversity survey revealed that the enrichment consisted entirely of class Halobacteria members belonging to the genera Halopenitus, Halosarcina, Natronomonas, Halosimplex, Halorubrum, Salinarchaeum and Haloterrigena. Of these, Halopenitus was the dominant group accounting for almost 91 % of the total sequences suggesting their potential role in degrading oxygenated aromatic compounds at extreme salinity. PMID:26995683

  9. Microbial respiration with chlorine oxyanions: diversity and physiological and biochemical properties of chlorate- and perchlorate-reducing microorganisms.

    Science.gov (United States)

    Liebensteiner, Martin G; Oosterkamp, Margreet J; Stams, Alfons J M

    2016-02-01

    Chlorine oxyanions are valuable electron acceptors for microorganisms. Recent findings have shed light on the natural formation of chlorine oxyanions in the environment. These suggest a permanent introduction of respective compounds on Earth, long before their anthropogenic manufacture. Microorganisms that are able to grow by the reduction of chlorate and perchlorate are affiliated with phylogenetically diverse lineages, spanning from the Proteobacteria to the Firmicutes and archaeal microorganisms. Microbial reduction of chlorine oxyanions can be found in diverse environments and different environmental conditions (temperature, salinities, pH). It commonly involves the enzymes perchlorate reductase (Pcr) or chlorate reductase (Clr) and chlorite dismutase (Cld). Horizontal gene transfer seems to play an important role for the acquisition of functional genes. Novel and efficient Clds were isolated from microorganisms incapable of growing on chlorine oxyanions. Archaea seem to use a periplasmic Nar-type reductase (pNar) for perchlorate reduction and lack a functional Cld. Chlorite is possibly eliminated by alternative (abiotic) reactions. This was already demonstrated for Archaeoglobus fulgidus, which uses reduced sulfur compounds to detoxify chlorite. A broad biochemical diversity of the trait, its environmental dispersal, and the occurrence of relevant enzymes in diverse lineages may indicate early adaptations of life toward chlorine oxyanions on Earth. PMID:26104311

  10. A Universal Phylogenetic Tree.

    Science.gov (United States)

    Offner, Susan

    2001-01-01

    Presents a universal phylogenetic tree suitable for use in high school and college-level biology classrooms. Illustrates the antiquity of life and that all life is related, even if it dates back 3.5 billion years. Reflects important evolutionary relationships and provides an exciting way to learn about the history of life. (SAH)

  11. Factors affecting Archaeal Lipid Compositions of the Sulfolobus Species

    Science.gov (United States)

    He, L.; Han, J.; Wei, Y.; Lin, L.; Wei, Y.; Zhang, C.

    2010-12-01

    Temperature is the best known variable affecting the distribution of the archaeal glycerol dibiphytanyl glycerol tetraethers (GDGTs) in marine and freshwater systems. Other variables such as pH, ionic strength, or bicarbonate concentration may also affect archaeal GDGTs in terrestrial systems. Studies of pure cultures can help us pinpoint the specific effects these variables may have on archaeal lipid distribution in natural environments. In this study, three Sulfolobus species (HG4, HB5-2, HB9-6) isolated from Tengchong hot springs (pH 2-3, temperature 73-90°C) in China were used to investigate the effects of temperature, pH, substrate, and type of strain on the composition of GDGTs. Results showed that increase in temperature had negative effects on the relative contents of GDGT-0 (no cyclopentyl rings), GDGT-1 (one cyclopentyl ring), GDGT-2 and GDGT-3 but positive effects on GDGT-4, GDGT-4', GDGT-5 and GDGT-5'. Increase in pH, on the other hand, had negative effects on GDGT-0, GDGT-1, GDGT-4', GDGT-5 and GDGT-5', and positive effects on GDGT-3 and GDGT-4. GDGT-2 remained relatively constant with changing pH. When the HG4 was grown on different substrates, GDGT-5 was five time more abundant in sucrose-grown cultures than in yeast extract- or sulfur- grown cultures, suggesting that carbohydrates may stimulate the production of GDGT-5. For all three species, the ring index (average number of rings) of GDGTs correlated positively with incubation temperature. In HG4, ring index was much lower at optimal pH (3.5) than at other pH values. Ring index of HB5-2 or HB9-6 is higher than that of HG4, suggesting that speciation may affect the degree of cyclization of GDGT of the Sulfolobus. These results indicate that individual archaeal lipids respond differently to changes in environmental variables, which may be also species specific.

  12. The archaeal TFIIE homologue facilitates transcription initiation by enhancing TATA-box recognition

    NARCIS (Netherlands)

    Bell, S.D.; Brinkman, A.B.; Oost, van der J.; Jackson, S.P.

    2001-01-01

    Transcription from many archaeal promoters can be reconstituted in vitro using recombinant TATA-box binding protein (TBP) and transcription factor B (TFB)—homologues of eukaryal TBP and TFIIB—together with purified RNA polymerase (RNAP). However, all archaeal genomes sequenced to date reveal the pre

  13. Microbial Diversity in a Venezuelan Orthoquartzite Cave is Dominated by the Chloroflexi (Class Ktedonobacterales and Thaumarchaeota Group I.1c.

    Directory of Open Access Journals (Sweden)

    Hazel A Barton

    2014-11-01

    Full Text Available The majority of caves are formed within limestone rock and hence our understanding of cave microbiology comes from carbonate-buffered systems. In this paper, we describe the microbial diversity of Roraima Sur Cave, an orthoquartzite (SiO4 cave within Roraima Tepui, Venezuela. The cave contains a high level of microbial activity when compared with other cave systems, as determined by an ATP-based luminescence assay and cell counting. Molecular phylogenetic analysis of microbial diversity within the cave demonstrate the dominance of Actinomycetales and Alphaproteobacteria in endolithic bacterial communities close to the entrance, while communities from deeper in the cave are dominated (82-84% by a unique clade of Ktedonobacterales within the Chloroflexi. While members of this phylum are commonly found in caves, this is the first identification of members of the Class Ktedonobacterales. An assessment of archaeal species demonstrates the dominance of phylotypes from the Thaumarchaeota Group I.1c (100%, which have previously been associated with acidic environments. While the Thaumarchaeota have been seen in numerous cave systems, the dominance of Group I.1c in Roraima Sur Cave is unique and a departure from the traditional archaeal community structure. Geochemical analysis of the cave environment suggests that water entering the cave, rather than the nutrient-limited orthoquartzite rock, provides the carbon and energy necessary for microbial community growth and subsistence, while the poor buffering capacity of quartzite or the low pH of the environment may be selecting for this unusual community structure. Together these data suggest that pH, imparted by the geochemistry of the host rock, can play as important a role in niche-differentiation in caves as in other environmental systems.

  14. Microbial diversity in a Venezuelan orthoquartzite cave is dominated by the Chloroflexi (Class Ktedonobacterales) and Thaumarchaeota Group I.1c.

    Science.gov (United States)

    Barton, Hazel A; Giarrizzo, Juan G; Suarez, Paula; Robertson, Charles E; Broering, Mark J; Banks, Eric D; Vaishampayan, Parag A; Venkateswaran, Kasthisuri

    2014-01-01

    The majority of caves are formed within limestone rock and hence our understanding of cave microbiology comes from carbonate-buffered systems. In this paper, we describe the microbial diversity of Roraima Sur Cave (RSC), an orthoquartzite (SiO4) cave within Roraima Tepui, Venezuela. The cave contains a high level of microbial activity when compared with other cave systems, as determined by an ATP-based luminescence assay and cell counting. Molecular phylogenetic analysis of microbial diversity within the cave demonstrates the dominance of Actinomycetales and Alphaproteobacteria in endolithic bacterial communities close to the entrance, while communities from deeper in the cave are dominated (82-84%) by a unique clade of Ktedonobacterales within the Chloroflexi. While members of this phylum are commonly found in caves, this is the first identification of members of the Class Ktedonobacterales. An assessment of archaeal species demonstrates the dominance of phylotypes from the Thaumarchaeota Group I.1c (100%), which have previously been associated with acidic environments. While the Thaumarchaeota have been seen in numerous cave systems, the dominance of Group I.1c in RSC is unique and a departure from the traditional archaeal community structure. Geochemical analysis of the cave environment suggests that water entering the cave, rather than the nutrient-limited orthoquartzite rock, provides the carbon and energy necessary for microbial community growth and subsistence, while the poor buffering capacity of quartzite or the low pH of the environment may be selecting for this unusual community structure. Together these data suggest that pH, imparted by the geochemistry of the host rock, can play as important a role in niche-differentiation in caves as in other environmental systems. PMID:25505450

  15. Phyloclimatic modeling: combining phylogenetics and bioclimatic modeling.

    Science.gov (United States)

    Yesson, C; Culham, A

    2006-10-01

    We investigate the impact of past climates on plant diversification by tracking the "footprint" of climate change on a phylogenetic tree. Diversity within the cosmopolitan carnivorous plant genus Drosera (Droseraceae) is focused within Mediterranean climate regions. We explore whether this diversity is temporally linked to Mediterranean-type climatic shifts of the mid-Miocene and whether climate preferences are conservative over phylogenetic timescales. Phyloclimatic modeling combines environmental niche (bioclimatic) modeling with phylogenetics in order to study evolutionary patterns in relation to climate change. We present the largest and most complete such example to date using Drosera. The bioclimatic models of extant species demonstrate clear phylogenetic patterns; this is particularly evident for the tuberous sundews from southwestern Australia (subgenus Ergaleium). We employ a method for establishing confidence intervals of node ages on a phylogeny using replicates from a Bayesian phylogenetic analysis. This chronogram shows that many clades, including subgenus Ergaleium and section Bryastrum, diversified during the establishment of the Mediterranean-type climate. Ancestral reconstructions of bioclimatic models demonstrate a pattern of preference for this climate type within these groups. Ancestral bioclimatic models are projected into palaeo-climate reconstructions for the time periods indicated by the chronogram. We present two such examples that each generate plausible estimates of ancestral lineage distribution, which are similar to their current distributions. This is the first study to attempt bioclimatic projections on evolutionary time scales. The sundews appear to have diversified in response to local climate development. Some groups are specialized for Mediterranean climates, others show wide-ranging generalism. This demonstrates that Phyloclimatic modeling could be repeated for other plant groups and is fundamental to the understanding of

  16. Energy for two: New archaeal lineages and the origin of mitochondria.

    Science.gov (United States)

    Martin, William F; Neukirchen, Sinje; Zimorski, Verena; Gould, Sven B; Sousa, Filipa L

    2016-09-01

    Metagenomics bears upon all aspects of microbiology, including our understanding of mitochondrial and eukaryote origin. Recently, ribosomal protein phylogenies show the eukaryote host lineage - the archaeal lineage that acquired the mitochondrion - to branch within the archaea. Metagenomic studies are now uncovering new archaeal lineages that branch more closely to the host than any cultivated archaea do. But how do they grow? Carbon and energy metabolism as pieced together from metagenome assemblies of these new archaeal lineages, such as the Deep Sea Archaeal Group (including Lokiarchaeota) and Bathyarchaeota, do not match the physiology of any cultivated microbes. Understanding how these new lineages live in their environment is important, and might hold clues about how mitochondria arose and how the eukaryotic lineage got started. Here we look at these exciting new metagenomic studies, what they say about archaeal physiology in modern environments, how they impact views on host-mitochondrion physiological interactions at eukaryote origin. PMID:27339178

  17. Asperisporium and Pantospora (Mycosphaerellaceae): epitypifications and phylogenetic placement

    OpenAIRE

    Minnis, A.M.; Kennedy, A.H.; Grenier, D.B.; Rehner, S.A.; Bischoff, J.F.

    2012-01-01

    The species-rich family Mycosphaerellaceae contains considerable morphological diversity and includes numerous anamorphic genera, many of which are economically important plant pathogens. Recent revisions and phylogenetic research have resulted in taxonomic instability. Ameliorating this problem requires phylogenetic placement of type species of key genera. We present an examination of the type species of the anamorphic Asperisporium and Pantospora. Cultures isolated from recent port intercep...

  18. Structure and cell biology of archaeal virus STIV.

    Science.gov (United States)

    Fu, Chi-yu; Johnson, Johnson E

    2012-04-01

    Recent investigations of archaeal viruses have revealed novel features of their structures and life cycles when compared to eukaryotic and bacterial viruses, yet there are structure-based unifying themes suggesting common ancestral relationships among dsDNA viruses in the three kingdoms of life. Sulfolobus solfataricus and the infecting virus Sulfolobus turreted icosahedral virus (STIV) is one of the well-established model systems to study archaeal virus replication and viral-host interactions. Reliable laboratory conditions to propagate STIV and available genetic tools allowed structural characterization of the virus and viral components that lead to the proposal of common capsid ancestry with PRD1 (bacteriophage), Adenovirus (eukaryotic virus) and PBCV (chlorellavirus). Microarray and proteomics approaches systematically analyzed viral replication and the corresponding host responses. Cellular cryo-electron tomography and thin-section EM studies uncovered the assembly and maturation pathway of STIV and revealed dramatic cellular ultra-structure changes upon infection. The viral-induced pyramid-like protrusions on cell surfaces represent a novel viral release mechanism and previously uncharacterized functions in viral replication. PMID:22482708

  19. Distribution of ether lipids and composition of the archaeal community in terrestrial geothermal springs: impact of environmental variables.

    Science.gov (United States)

    Xie, Wei; Zhang, Chuanlun L; Wang, Jinxiang; Chen, Yufei; Zhu, Yuanqing; de la Torre, José R; Dong, Hailiang; Hartnett, Hilairy E; Hedlund, Brian P; Klotz, Martin G

    2015-05-01

    Archaea can respond to changes in the environment by altering the composition of their membrane lipids, for example, by modification of the abundance and composition of glycerol dialkyl glycerol tetraethers (GDGTs). Here, we investigated the abundance and proportions of polar GDGTs (P-GDGTs) and core GDGTs (C-GDGTs) sampled in different seasons from Tengchong hot springs (Yunnan, China), which encompassed a pH range of 2.5-10.1 and a temperature range of 43.7-93.6°C. The phylogenetic composition of the archaeal community (reanalysed from published work) divided the Archaea in spring sediment samples into three major groups that corresponded with spring pH: acidic, circumneutral and alkaline. Cluster analysis showed correlation between spring pH and the composition of P- and C-GDGTs and archaeal 16S rRNA genes, indicating an intimate link between resident Archaea and the distribution of P- and C-GDGTs in Tengchong hot springs. The distribution of GDGTs in Tengchong springs was also significantly affected by temperature; however, the relationship was weaker than with pH. Analysis of published datasets including samples from Tibet, Yellowstone and the US Great Basin hot springs revealed a similar relationship between pH and GDGT content. Specifically, low pH springs had higher concentrations of GDGTs with high numbers of cyclopentyl rings than neutral and alkaline springs, which is consistent with the predominance of high cyclopentyl ring-characterized Sulfolobales and Thermoplasmatales present in some of the low pH springs. Our study suggests that the resident Archaea in these hot springs are acclimated if not adapted to low pH by their genetic capacity to effect the packing density of their membranes by increasing cyclopentyl rings in GDGTs at the rank of community. PMID:25142282

  20. DNA barcoding and phylogenetic relationships in Timaliidae.

    Science.gov (United States)

    Huang, Z H; Ke, D H

    2015-01-01

    The Timaliidae, a diverse family of oscine passerine birds, has long been a subject of debate regarding its phylogeny. The mitochondrial cytochrome c oxidase subunit I (COI) gene has been used as a powerful marker for identification and phylogenetic studies of animal species. In the present study, we analyzed the COI barcodes of 71 species from 21 genera belonging to the family Timaliidae. Every bird species possessed a barcode distinct from that of other bird species. Kimura two-parameter (K2P) distances were calculated between barcodes. The average genetic distance between species was 18 times higher than the average genetic distance within species. The neighbor-joining method was used to construct a phylogenetic tree and all the species could be discriminated by their distinct clades within the phylogenetic tree. The results indicate that some currently recognized babbler genera might not be monophyletic, with the COI gene data supporting the hypothesis of polyphyly for Garrulax, Alcippe, and Minla. Thus, DNA barcoding is an effective molecular tool for Timaliidae species identification and phylogenetic inference. PMID:26125793

  1. Phylogenetic molecular function annotation

    OpenAIRE

    Barbara E Engelhardt; Jordan, Michael I.; Repo, Susanna T; Brenner, Steven E

    2009-01-01

    It is now easier to discover thousands of protein sequences in a new microbial genome than it is to biochemically characterize the specific activity of a single protein of unknown function. The molecular functions of protein sequences have typically been predicted using homology-based computational methods, which rely on the principle that homologous proteins share a similar function. However, some protein families include groups of proteins with different molecular functions. A phylogenetic ...

  2. Molecular phylogenetics before sequences

    OpenAIRE

    Mark A. Ragan; Bernard, Guillaume,; Chan, Cheong Xin

    2014-01-01

    From 1971 to 1985, Carl Woese and colleagues generated oligonucleotide catalogs of 16S/18S rRNAs from more than 400 organisms. Using these incomplete and imperfect data, Carl and his colleagues developed unprecedented insights into the structure, function, and evolution of the large RNA components of the translational apparatus. They recognized a third domain of life, revealed the phylogenetic backbone of bacteria (and its limitations), delineated taxa, and explored the tempo and mode of micr...

  3. Canonical phylogenetic ordination.

    Science.gov (United States)

    Giannini, Norberto P

    2003-10-01

    A phylogenetic comparative method is proposed for estimating historical effects on comparative data using the partitions that compose a cladogram, i.e., its monophyletic groups. Two basic matrices, Y and X, are defined in the context of an ordinary linear model. Y contains the comparative data measured over t taxa. X consists of an initial tree matrix that contains all the xj monophyletic groups (each coded separately as a binary indicator variable) of the phylogenetic tree available for those taxa. The method seeks to define the subset of groups, i.e., a reduced tree matrix, that best explains the patterns in Y. This definition is accomplished via regression or canonical ordination (depending on the dimensionality of Y) coupled with Monte Carlo permutations. It is argued here that unrestricted permutations (i.e., under an equiprobable model) are valid for testing this specific kind of groupwise hypothesis. Phylogeny is either partialled out or, more properly, incorporated into the analysis in the form of component variation. Direct extensions allow for testing ecomorphological data controlled by phylogeny in a variation partitioning approach. Currently available statistical techniques make this method applicable under most univariate/multivariate models and metrics; two-way phylogenetic effects can be estimated as well. The simplest case (univariate Y), tested with simulations, yielded acceptable type I error rates. Applications presented include examples from evolutionary ethology, ecology, and ecomorphology. Results showed that the new technique detected previously overlooked variation clearly associated with phylogeny and that many phylogenetic effects on comparative data may occur at particular groups rather than across the entire tree. PMID:14530135

  4. Tracing the Archaeal Origins of Eukaryotic Membrane-Trafficking System Building Blocks.

    Science.gov (United States)

    Klinger, Christen M; Spang, Anja; Dacks, Joel B; Ettema, Thijs J G

    2016-06-01

    In contrast to prokaryotes, eukaryotic cells are characterized by a complex set of internal membrane-bound compartments. A subset of these, and the protein machineries that move material between them, define the membrane-trafficking system (MTS), the emergence of which represents a landmark in eukaryotic evolution. Unlike mitochondria and plastids, MTS organelles have autogenous origins. Much of the MTS machinery is composed of building blocks, including small GTPase, coiled-coil, beta-propeller + alpha-solenoid, and longin domains. Despite the identification of prokaryotic proteins containing these domains, only few represent direct orthologues, leaving the origins and early evolution of the MTS poorly understood. Here, we present an in-depth analysis of MTS building block homologues in the composite genome of Lokiarchaeum, the recently discovered archaeal sister clade of eukaryotes, yielding several key insights. We identify two previously unreported Eukaryotic Signature Proteins; orthologues of the Gtr/Rag family GTPases, involved in target of rapamycin complex signaling, and of the RLC7 dynein component. We could not identify golgin or SNARE (coiled-coil) or beta-propeller + alpha-solenoid orthologues, nor typical MTS domain fusions, suggesting that these either were lost from Lokiarchaeum or emerged later in eukaryotic evolution. Furthermore, our phylogenetic analyses of lokiarchaeal GTPases support a split into Ras-like and Arf-like superfamilies, with different prokaryotic antecedents, before the advent of eukaryotes. While no GTPase activating proteins or exchange factors were identified, we show that Lokiarchaeum encodes numerous roadblock domain proteins and putative longin domain proteins, confirming the latter's origin from Archaea. Altogether, our study provides new insights into the emergence and early evolution of the eukaryotic membrane-trafficking system. PMID:26893300

  5. Global pattern of phylogenetic species composition of shark and its conservation priority

    OpenAIRE

    Chen, Hungyen; Kishino, Hirohisa

    2015-01-01

    Abstract The diversity of marine communities is in striking contrast with the diversity of terrestrial communities. In all oceans, species richness is low in tropical areas and high at latitudes between 20 and 40°. While species richness is a primary metric used in conservation and management strategies, it is important to take into account the complex phylogenetic patterns of species compositions within communities. We measured the phylogenetic skew and diversity of shark communities through...

  6. Magnetic Au Nanoparticles on Archaeal S-Layer Ghosts as Templates

    Directory of Open Access Journals (Sweden)

    Sonja Selenska-Pobell

    2011-10-01

    Full Text Available Cell‐ghosts representing empty cells of the archaeon Sulfolobus acidocaldarius, consisting only of their highly ordered and unusually stable outermost proteinaceous surface layer (S‐layer, were used as templates for Au nanoparticles fabrication. The properties of these archaeal Au nanoparticles differ significantly from those produced earlier by us onto bacterial S‐layer sheets. The archaeal Au nanoparticles, with a size of about 2.5 nm, consist exclusively of metallic Au(0, while those produced on the bacterial S‐layer had a size of about 4 nm and represented a mixture of Au(0 and Au(III in the ratio of 40 to 60 %. The most impressive feature of the archaeal Au nanoparticles is that they are strongly paramagnetic, in contrast to the bacterial ones and also to bulk gold. SQUID magnetometry and XMCD measurements demonstrated that the archaeal Au nanoparticles possess a rather large magnetic moment of about 0.1 µB/atom. HR‐ TEM‐EDX analysis revealed that the archaeal Au nanoparticles are linked to the sulfur atoms of the thiol groups of the amino acid cysteine, characteristic only for archaeal S‐layers. This is the first study demonstrating the formation of such unusually strong magnetic Au nanoparticles on a non‐modified archaeal S‐layer.

  7. Clustering with phylogenetic tools in astrophysics

    CERN Document Server

    Fraix-Burnet, Didier

    2016-01-01

    Phylogenetic approaches are finding more and more applications outside the field of biology. Astrophysics is no exception since an overwhelming amount of multivariate data has appeared in the last twenty years or so. In particular, the diversification of galaxies throughout the evolution of the Universe quite naturally invokes phylogenetic approaches. We have demonstrated that Maximum Parsimony brings useful astrophysical results, and we now proceed toward the analyses of large datasets for galaxies. In this talk I present how we solve the major difficulties for this goal: the choice of the parameters, their discretization, and the analysis of a high number of objects with an unsupervised NP-hard classification technique like cladistics. 1. Introduction How do the galaxy form, and when? How did the galaxy evolve and transform themselves to create the diversity we observe? What are the progenitors to present-day galaxies? To answer these big questions, observations throughout the Universe and the physical mode...

  8. Archaeal enrichment in the hypoxic zone in the northern Gulf of Mexico.

    Science.gov (United States)

    Gillies, Lauren E; Thrash, J Cameron; deRada, Sergio; Rabalais, Nancy N; Mason, Olivia U

    2015-10-01

    Areas of low oxygen have spread exponentially over the past 40 years, and are cited as a key stressor on coastal ecosystems. The world's second largest coastal hypoxic (≤ 2 mg of O2 l(-1)) zone occurs annually in the northern Gulf of Mexico. The net effect of hypoxia is the diversion of energy flow away from higher trophic levels to microorganisms. This energy shunt is consequential to the overall productivity of hypoxic water masses and the ecosystem as a whole. In this study, water column samples were collected at 39 sites in the nGOM, 21 of which were hypoxic. Analysis of the microbial community along a hypoxic to oxic dissolved oxygen gradient revealed that the relative abundance (iTag) of Thaumarchaeota species 16S rRNA genes (> 40% of the microbial community in some hypoxic samples), the absolute abundance (quantitative polymerase chain reaction; qPCR) of Thaumarchaeota 16S rRNA genes and archaeal ammonia-monooxygenase gene copy number (qPCR) were significantly higher in hypoxic samples. Spatial interpolation of the microbial and chemical data revealed a continuous, shelfwide band of low dissolved oxygen waters that were dominated by Thaumarchaeota (and Euryarchaeota), amoA genes and high concentrations of phosphate in the nGOM, thus implicating physicochemical forcing on microbial abundance. PMID:25818237

  9. A re-evaluation of the archaeal membrane lipid biosynthetic pathway.

    Science.gov (United States)

    Villanueva, Laura; Damsté, Jaap S Sinninghe; Schouten, Stefan

    2014-06-01

    Archaea produce unique membrane lipids in which isoprenoid alkyl chains are bound to glycerol moieties via ether linkages. As cultured representatives of the Archaea have become increasingly available throughout the past decade, archaeal genomic and membrane lipid-composition data have also become available. In this Analysis article, we compare the amino acid sequences of the key enzymes of the archaeal ether-lipid biosynthesis pathway and critically evaluate past studies on the biochemical functions of these enzymes. We propose an alternative archaeal lipid biosynthetic pathway that is based on a 'multiple-key, multiple-lock' mechanism. PMID:24801941

  10. Archaeal promoter architecture and mechanism of gene activation.

    Science.gov (United States)

    Peng, Nan; Ao, Xiang; Liang, Yun Xiang; She, Qunxin

    2011-01-01

    Sulfolobus solfataricus and Sulfolobus islandicus contain several genes exhibiting D-arabinose-inducible expression and these systems are ideal for studying mechanisms of archaeal gene expression. At sequence level, only two highly conserved cis elements are present on the promoters: a regulatory element named ara box directing arabinose-inducible expression and the basal promoter element TATA, serving as the binding site for the TATA-binding protein. Strikingly, these promoters possess a modular structure that allows an essentially inactive basal promoter to be strongly activated. The invoked mechanisms include TFB (transcription factor B) recruitment by the ara-box-binding factor to activate gene expression and modulation of TFB recruitment efficiency to yield differential gene expression. PMID:21265754

  11. Useful scars: Physics of the capsids of archaeal viruses

    Science.gov (United States)

    Perotti, L. E.; Dharmavaram, S.; Klug, W. S.; Marian, J.; Rudnick, J.; Bruinsma, R. F.

    2016-07-01

    We propose a physical model for the capsids of tailed archaeal viruses as viscoelastic membranes under tension. The fluidity is generated by thermal motion of scarlike structures that are an intrinsic feature of the ground state of large particle arrays covering surfaces with nonzero Gauss curvature. The tension is generated by a combination of the osmotic pressure of the enclosed genome and an extension force generated by filamentous structure formation that drives the formation of the tails. In continuum theory, the capsid has the shape of a surface of constant mean curvature: an unduloid. Particle arrays covering unduloids are shown to exhibit pronounced subdiffusive and diffusive single-particle transport at temperatures that are well below the melting temperature of defect-free particle arrays on a surface with zero Gauss curvature.

  12. Fast phylogenetic DNA barcoding

    DEFF Research Database (Denmark)

    Terkelsen, Kasper Munch; Boomsma, Wouter Krogh; Willerslev, Eske;

    2008-01-01

    We present a heuristic approach to the DNA assignment problem based on phylogenetic inferences using constrained neighbour joining and non-parametric bootstrapping. We show that this method performs as well as the more computationally intensive full Bayesian approach in an analysis of 500 insect...... DNA sequences obtained from GenBank. We also analyse a previously published dataset of environmental DNA sequences from soil from New Zealand and Siberia, and use these data to illustrate the fact that statistical approaches to the DNA assignment problem allow for more appropriate criteria...... for determining the taxonomic level at which a particular DNA sequence can be assigned....

  13. The Role of Multiple Transcription Factors In Archaeal Gene Expression

    Energy Technology Data Exchange (ETDEWEB)

    Charles J. Daniels

    2008-09-23

    Since the inception of this research program, the project has focused on two central questions: What is the relationship between the 'eukaryal-like' transcription machinery of archaeal cells and its counterparts in eukaryal cells? And, how does the archaeal cell control gene expression using its mosaic of eukaryal core transcription machinery and its bacterial-like transcription regulatory proteins? During the grant period we have addressed these questions using a variety of in vivo approaches and have sought to specifically define the roles of the multiple TATA binding protein (TBP) and TFIIB-like (TFB) proteins in controlling gene expression in Haloferax volcanii. H. volcanii was initially chosen as a model for the Archaea based on the availability of suitable genetic tools; however, later studies showed that all haloarchaea possessed multiple tbp and tfb genes, which led to the proposal that multiple TBP and TFB proteins may function in a manner similar to alternative sigma factors in bacterial cells. In vivo transcription and promoter analysis established a clear relationship between the promoter requirements of haloarchaeal genes and those of the eukaryal RNA polymerase II promoter. Studies on heat shock gene promoters, and the demonstration that specific tfb genes were induced by heat shock, provided the first indication that TFB proteins may direct expression of specific gene families. The construction of strains lacking tbp or tfb genes, coupled with the finding that many of these genes are differentially expressed under varying growth conditions, provided further support for this model. Genetic tools were also developed that led to the construction of insertion and deletion mutants, and a novel gene expression scheme was designed that allowed the controlled expression of these genes in vivo. More recent studies have used a whole genome array to examine the expression of these genes and we have established a linkage between the expression of

  14. Characterization of Olkiluoto bacterial and archaeal communities by 454 pyrosequencing

    International Nuclear Information System (INIS)

    Recent advancement in sequencing technologies, 'Next Generation Sequencing', such as FLX 454 pyrosequencing has made it possible to obtain large amounts of sequence data where previously only few sequences could be obtained. This technique is especially useful for the study of community composition of uncultured microbial populations in environmental samples. In this project, the FLX 454 pyrosequencing technique was used to obtain up to 20 000 16S rRNA sequences or 10 000 mRNA sequences from each sample for identification of the microbial species composition as well as for comparison of the microbial communities between different samples. This project focused on the characterization of active microbial communities in the groundwater at the final disposal site of high radioactive wastes in Olkiluoto by FLX 454 pyrosequencing of the bacterial and archaeal ribosomal RNA as well as of the mRNA transcripts of the dsrB gene and mcrA gene of sulphate reducing bacteria and methanogenic archaea, respectively. Specific emphasis was put on studying the relationship of active and latent sulphate reducers and methanogens by qPCR due to their important roles in deep geobiochemical processes connected to copper corrosion. Seven packered boreholes were sampled anaerobically in Olkiluoto during 2009-2010. Groundwater was pumped from specific depths and the microbial cells werecollected by filtration on a membrane. Active microbial communities were studied based on RNA extracted from the membranes and translated to copy DNA, followed by sequencing by 454 Tag pyrosequencing. A total of 27 different bacterial and 17 archaeal taxonomic groups were detected

  15. Characterization of Olkiluoto bacterial and archaeal communities by 454 pyrosequencing

    Energy Technology Data Exchange (ETDEWEB)

    Bomberg, M.; Nyyssoenen, M.; Itaevaara, M. [VTT Technical Research Centre of Finland, Espoo (Finland)

    2012-06-15

    Recent advancement in sequencing technologies, 'Next Generation Sequencing', such as FLX 454 pyrosequencing has made it possible to obtain large amounts of sequence data where previously only few sequences could be obtained. This technique is especially useful for the study of community composition of uncultured microbial populations in environmental samples. In this project, the FLX 454 pyrosequencing technique was used to obtain up to 20 000 16S rRNA sequences or 10 000 mRNA sequences from each sample for identification of the microbial species composition as well as for comparison of the microbial communities between different samples. This project focused on the characterization of active microbial communities in the groundwater at the final disposal site of high radioactive wastes in Olkiluoto by FLX 454 pyrosequencing of the bacterial and archaeal ribosomal RNA as well as of the mRNA transcripts of the dsrB gene and mcrA gene of sulphate reducing bacteria and methanogenic archaea, respectively. Specific emphasis was put on studying the relationship of active and latent sulphate reducers and methanogens by qPCR due to their important roles in deep geobiochemical processes connected to copper corrosion. Seven packered boreholes were sampled anaerobically in Olkiluoto during 2009-2010. Groundwater was pumped from specific depths and the microbial cells werecollected by filtration on a membrane. Active microbial communities were studied based on RNA extracted from the membranes and translated to copy DNA, followed by sequencing by 454 Tag pyrosequencing. A total of 27 different bacterial and 17 archaeal taxonomic groups were detected.

  16. Plant diversity predicts beta but not alpha diversity of soil microbes across grasslands worldwide

    Science.gov (United States)

    Prober, Suzanne M.; Leff, Jonathan W.; Bates, Scott T.; Borer, Elizabeth T.; Firn, Jennifer; Harpole, W. Stanley; Lind, Eric M.; Seabloom, Eric W.; Adler, Peter B.; Bakker, Jonathan D.; Cleland, Elsa E.; DeCrappeo, Nicole; DeLorenze, Elizabeth; Hagenah, Nicole; Hautier, Yann; Hofmockel, Kirsten S.; Kirkman, Kevin P.; Knops, Johannes M. H.; La Pierre, Kimberly J.; MacDougall, Andrew S.; McCulley, Rebecca L.; Mitchell, Charles E.; Risch, Anita C.; Schuetz, Martin; Stevens, Carly J.; Williams, Ryan J.; Fierer, Noah

    2015-01-01

    Aboveground–belowground interactions exert critical controls on the composition and function of terrestrial ecosystems, yet the fundamental relationships between plant diversity and soil microbial diversity remain elusive. Theory predicts predominantly positive associations but tests within single sites have shown variable relationships, and associations between plant and microbial diversity across broad spatial scales remain largely unexplored. We compared the diversity of plant, bacterial, archaeal and fungal communities in one hundred and forty-five 1 m2 plots across 25 temperate grassland sites from four continents. Across sites, the plant alpha diversity patterns were poorly related to those observed for any soil microbial group. However, plant beta diversity (compositional dissimilarity between sites) was significantly correlated with the beta diversity of bacterial and fungal communities, even after controlling for environmental factors. Thus, across a global range of temperate grasslands, plant diversity can predict patterns in the composition of soil microbial communities, but not patterns in alpha diversity.

  17. Plant diversity predicts beta but not alpha diversity of soil microbes across grasslands worldwide.

    Science.gov (United States)

    Prober, Suzanne M; Leff, Jonathan W; Bates, Scott T; Borer, Elizabeth T; Firn, Jennifer; Harpole, W Stanley; Lind, Eric M; Seabloom, Eric W; Adler, Peter B; Bakker, Jonathan D; Cleland, Elsa E; DeCrappeo, Nicole M; DeLorenze, Elizabeth; Hagenah, Nicole; Hautier, Yann; Hofmockel, Kirsten S; Kirkman, Kevin P; Knops, Johannes M H; La Pierre, Kimberly J; MacDougall, Andrew S; McCulley, Rebecca L; Mitchell, Charles E; Risch, Anita C; Schuetz, Martin; Stevens, Carly J; Williams, Ryan J; Fierer, Noah

    2015-01-01

    Aboveground-belowground interactions exert critical controls on the composition and function of terrestrial ecosystems, yet the fundamental relationships between plant diversity and soil microbial diversity remain elusive. Theory predicts predominantly positive associations but tests within single sites have shown variable relationships, and associations between plant and microbial diversity across broad spatial scales remain largely unexplored. We compared the diversity of plant, bacterial, archaeal and fungal communities in one hundred and forty-five 1 m(2) plots across 25 temperate grassland sites from four continents. Across sites, the plant alpha diversity patterns were poorly related to those observed for any soil microbial group. However, plant beta diversity (compositional dissimilarity between sites) was significantly correlated with the beta diversity of bacterial and fungal communities, even after controlling for environmental factors. Thus, across a global range of temperate grasslands, plant diversity can predict patterns in the composition of soil microbial communities, but not patterns in alpha diversity. PMID:25430889

  18. Global pattern of phylogenetic species composition of shark and its conservation priority.

    Science.gov (United States)

    Chen, Hungyen; Kishino, Hirohisa

    2015-10-01

    The diversity of marine communities is in striking contrast with the diversity of terrestrial communities. In all oceans, species richness is low in tropical areas and high at latitudes between 20 and 40°. While species richness is a primary metric used in conservation and management strategies, it is important to take into account the complex phylogenetic patterns of species compositions within communities. We measured the phylogenetic skew and diversity of shark communities throughout the world. We found that shark communities in tropical seas were highly phylogenetically skewed, whereas temperate sea communities had phylogenetically diversified species compositions. Interestingly, although geographically distant from one another, tropical sea communities were all highly skewed toward requiem sharks (Carcharhinidae), hammerhead sharks (Sphyrnidae), and whale sharks (Rhincodon typus). Worldwide, the greatest phylogenetic evenness in terms of clades was found in the North Sea and coastal regions of countries in temperate zones, such as the United Kingdom, Ireland, southern Australia, and Chile. This study is the first to examine patterns of phylogenetic diversity of shark communities on a global scale. Our findings suggest that when establishing conservation activities, it is important to take full account of phylogenetic patterns of species composition and not solely use species richness as a target. Protecting areas of high phylogenetic diversity in sharks, which were identified in this study, could form a broader strategy for protecting other threatened marine species. PMID:26819704

  19. Analysis of Bacterial and Archaeal Communities along a High-Molecular-Weight Polyacrylamide Transportation Pipeline System in an Oil Field

    Directory of Open Access Journals (Sweden)

    Cai-Yun Li

    2015-04-01

    Full Text Available Viscosity loss of high-molecular-weight partially hydrolyzed polyacrylamide (HPAM solution was observed in a water injection pipeline before being injected into subterranean oil wells. In order to investigate the possible involvement of microorganisms in HPAM viscosity loss, both bacterial and archaeal community compositions of four samples collected from different points of the transportation pipeline were analyzed using PCR-amplification of the 16S rRNA gene and clone library construction method together with the analysis of physicochemical properties of HPAM solution and environmental factors. Further, the relationship between environmental factors and HPAM properties with microorganisms were delineated by canonical correspondence analysis (CCA. Diverse bacterial and archaeal groups were detected in the four samples. The microbial community of initial solution S1 gathered from the make-up tank is similar to solution S2 gathered from the first filter, and that of solution S3 obtained between the first and the second filter is similar to that of solution S4 obtained between the second filter and the injection well. Members of the genus Acinetobacter sp. were detected with high abundance in S3 and S4 in which HPAM viscosity was considerably reduced, suggesting that they likely played a considerable role in HPAM viscosity loss. This study presents information on microbial community diversity in the HPAM transportation pipeline and the possible involvement of microorganisms in HPAM viscosity loss and biodegradation. The results will help to understand the microbial community contribution made to viscosity change and are beneficial for providing information for microbial control in oil fields.

  20. Non-extremophilic 'extremophiles' - Archaeal dominance in the subsurface and their implication for life

    Science.gov (United States)

    Reitschuler, Christoph; Lins, Philipp; Illmer, Paul

    2014-05-01

    strategies was applied as well as physiological analyses, comprising HPLC and GC analyses, and molecular approaches, covering end-point and quantitative PCRs, DGGE, cloning, and sequencing analyses. Outstanding in the course of this research was that assumed non-extremophilic Archaea clearly outnumbered bacteria within the different moonmilk deposits, while fungi were only of minor importance. Moreover, the Archaeal species formed a constant element within the investigated samples, while bacteria and fungi showed a much more diverse and inhomogeneous community pattern. This indicates that the Archaea might constitute the central element within the microbial communities, holding key positions in nutrient and energy-cycles. Furthermore, it was possible to cultivate the Archaeal community over a certain time period, demonstrating that so far uncultured or as 'not cultivable' regarded organisms are accessible with certain cultivation strategies. On the other hand the vast majority of bacterial and fungal representatives are in close relation to species, which are valuable concerning biotechnological or medical applications. Summing up, further research on cave microbiomes, especially Archaea, might be reasonable with regards to life's evolution, global nutrient cycles, requirements for possible refuges of extraterrestrial life forms and also concerning new technological applications.

  1. Phylogenetic comparative assembly

    Directory of Open Access Journals (Sweden)

    Husemann Peter

    2010-01-01

    Full Text Available Abstract Background Recent high throughput sequencing technologies are capable of generating a huge amount of data for bacterial genome sequencing projects. Although current sequence assemblers successfully merge the overlapping reads, often several contigs remain which cannot be assembled any further. It is still costly and time consuming to close all the gaps in order to acquire the whole genomic sequence. Results Here we propose an algorithm that takes several related genomes and their phylogenetic relationships into account to create a graph that contains the likelihood for each pair of contigs to be adjacent. Subsequently, this graph can be used to compute a layout graph that shows the most promising contig adjacencies in order to aid biologists in finishing the complete genomic sequence. The layout graph shows unique contig orderings where possible, and the best alternatives where necessary. Conclusions Our new algorithm for contig ordering uses sequence similarity as well as phylogenetic information to estimate adjacencies of contigs. An evaluation of our implementation shows that it performs better than recent approaches while being much faster at the same time.

  2. Mapping phylogenetic endemism in R using georeferenced branch extents

    Science.gov (United States)

    Guerin, Greg R.; Lowe, Andrew J.

    2015-12-01

    Applications are needed to map biodiversity from large-scale species occurrence datasets whilst seamlessly integrating with existing functions in R. Phylogenetic endemism (PE) is a biodiversity measure based on range-restricted phylogenetic diversity (PD). Current implementations use area of occupancy (AOO) or frequency to estimate the spatial range of branch-length (i.e. phylogenetic range-rarity), rather than extent of occurrence (EOO; i.e. georeferenced phylogenetic endemism), which is known to produce different range estimates. We present R functions to map PD or PE weighted by AOO or EOO (new georeferenced implementation), taking as inputs georeferenced species occurrences and a phylogeny. Non-parametric statistics distinguish PD/PE from trivial correlates of species richness and sampling intensity.

  3. Changes in northern Gulf of Mexico sediment bacterial and archaeal communities exposed to hypoxia

    Science.gov (United States)

    Biogeochemical changes in marine sediments during coastal water hypoxia are well described, but less is known about underlying changes in microbial communities. Bacterial and archaeal communities in Louisiana continental shelf (LCS) hypoxic zone sediments were characterized by py...

  4. The essence of being extremophilic : the role of the unique archaeal membrane lipids

    NARCIS (Netherlands)

    Vossenberg, Jack L.C.M. van de; Driessen, Arnold J.M.; Konings, Wil N.

    1998-01-01

    In extreme environments, mainly Archaea are encountered. The archaeal cytoplasmic membrane contains unique ether lipids that cannot easily be degraded, are temperature- and mechanically resistant, and highly salt tolerant. Moreover, thermophilic and extreme acidophilic Archaea possess membrane-spann

  5. Effect of soil properties and hydrology on Archaeal community composition in three temperate grasslands on peat

    DEFF Research Database (Denmark)

    Görres, Carolyn-Monika; Conrad, Ralf; Petersen, Søren O

    2013-01-01

    Grasslands established on drained peat soils are regarded as negligible methane (CH4) sources; however, they can still exhibit considerable soil CH4 dynamics. We investigated archaeal community composition in two different fen peat soils and one bog peat soil under permanent grassland in Denmark....... We used terminal restriction fragment length polymorphism (T-RFLP) fingerprinting and clone libraries to characterize the soils' archaeal community composition to gain a better understanding of relationships between peat properties and land use, respectively, and CH4 dynamics. Samples were taken...... at three different depths and at four different seasons. Archaeal community composition varied considerably between the three peatlands and, to a certain degree, also with peat depth, but seemed to be quite stable at individual sampling depths throughout the year. Archaeal community composition was mainly...

  6. Spatial and temporal patterns in the microbial diversity of a meromictic soda lake in Washington State.

    Science.gov (United States)

    Dimitriu, Pedro A; Pinkart, Holly C; Peyton, Brent M; Mormile, Melanie R

    2008-08-01

    The microbial community diversity and composition of meromictic Soap Lake were studied using culture-dependent and culture-independent approaches. The water column and sediments were sampled monthly for a year. Denaturing gradient gel electrophoresis of bacterial and archaeal 16S rRNA genes showed an increase in diversity with depth for both groups. Late-summer samples harbored the highest prokaryotic diversity, and the bacteria exhibited less seasonal variability than the archaea. Most-probable-number assays targeting anaerobic microbial guilds were performed to compare summer and fall samples. In both seasons, the anoxic samples appeared to be dominated by lactate-oxidizing sulfate-reducing prokaryotes. High numbers of lactate- and acetate-oxidizing iron-reducing bacteria, as well as fermentative microorganisms, were also found, whereas the numbers of methanogens were low or methanogens were undetectable. The bacterial community composition of summer and fall samples was also assessed by constructing 16S rRNA gene clone libraries. A total of 508 sequences represented an estimated >1,100 unique operational taxonomic units, most of which were from the monimolimnion, and the summer samples were more diverse than the fall samples (Chao1 = 530 and Chao1 = 295, respectively). For both seasons, the mixolimnion sequences were dominated by Gammaproteobacteria, and the chemocline and monimolimnion libraries were dominated by members of the low-G+C-content group, followed by the Cytophaga-Flexibacter-Bacteroides (CFB) group; the mixolimnion sediments contained sequences related to uncultured members of the Chloroflexi and the CFB group. Community overlap and phylogenetic analyses, however, not only demonstrated that there was a high degree of spatial turnover but also suggested that there was a degree of temporal variability due to differences in the members and structures of the communities. PMID:18552187

  7. Response of Archaeal Communities in Beach Sediments to Spilled Oil and Bioremediation

    OpenAIRE

    Röling, Wilfred F. M.; Couto de Brito, Ivana R.; Swannell, Richard P. J.; Head, Ian M.

    2004-01-01

    While the contribution of Bacteria to bioremediation of oil-contaminated shorelines is well established, the response of Archaea to spilled oil and bioremediation treatments is unknown. The relationship between archaeal community structure and oil spill bioremediation was examined in laboratory microcosms and in a bioremediation field trial. 16S rRNA gene-based PCR and denaturing gradient gel analysis revealed that the archaeal community in oil-free laboratory microcosms was stable for 26 day...

  8. Are mimics monophyletic? The necessity of phylogenetic hypothesis tests in character evolution

    OpenAIRE

    Prudic Kathleen L; Oliver Jeffrey C

    2010-01-01

    Abstract Background The processes governing the origin and maintenance of mimetic phenotypes can only be understood in a phylogenetic framework. Phylogenetic estimates of evolutionary relationships can provide a context for analyses of character evolution; however, when phylogenetic estimates conflict, rigorous analyses of alternative evolutionary histories are necessary to determine the likelihood of a specific history giving rise to the observed pattern of diversity. The polyphenic butterfl...

  9. Phylogenetic community ecology of soil biodiversity using mitochondrial metagenomics.

    Science.gov (United States)

    Andújar, Carmelo; Arribas, Paula; Ruzicka, Filip; Crampton-Platt, Alex; Timmermans, Martijn J T N; Vogler, Alfried P

    2015-07-01

    High-throughput DNA methods hold great promise for the study of taxonomically intractable mesofauna of the soil. Here, we assess species diversity and community structure in a phylogenetic framework, by sequencing total DNA from bulk specimen samples and assembly of mitochondrial genomes. The combination of mitochondrial metagenomics and DNA barcode sequencing of 1494 specimens in 69 soil samples from three geographic regions in southern Iberia revealed >300 species of soil Coleoptera (beetles) from a broad spectrum of phylogenetic lineages. A set of 214 mitochondrial sequences longer than 3000 bp was generated and used to estimate a well-supported phylogenetic tree of the order Coleoptera. Shorter sequences, including cox1 barcodes, were placed on this mitogenomic tree. Raw Illumina reads were mapped against all available sequences to test for species present in local samples. This approach simultaneously established the species richness, phylogenetic composition and community turnover at species and phylogenetic levels. We find a strong signature of vertical structuring in soil fauna that shows high local community differentiation between deep soil and superficial horizons at phylogenetic levels. Within the two vertical layers, turnover among regions was primarily at the tip (species) level and was stronger in the deep soil than leaf litter communities, pointing to layer-mediated drivers determining species diversification, spatial structure and evolutionary assembly of soil communities. This integrated phylogenetic framework opens the application of phylogenetic community ecology to the mesofauna of the soil, among the most diverse and least well-understood ecosystems, and will propel both theoretical and applied soil science. PMID:25865150

  10. Pyrosequencing reveals the influence of elevated atmospheric CO2 on the composition of archaeal communities in the rhizosphere of C3 and C4 crops

    Science.gov (United States)

    Nelson, D. M.; Cann, I. K.; Mackie, R. I.

    2008-12-01

    The projected increase in atmospheric CO2 concentrations throughout the 21st century is likely to increase aboveground and belowground plant productivity and cause changes in the quantity and quality of plant root exudates, although plants using C4 photosynthesis are likely to be only affected during times of drought (Leakey et al., 2006, Plant Physiology, 140, 779). Evidence is emerging from molecular tools that these changes may influence the abundance and composition of soil microbial communities that regulate key soil processes, such as nitrogen cycling (Lesaulnier et al., 2008, Environmental Microbiology, 10, 926). However, most molecular tools are not well-suited for comparing multiple samples at great sequencing depth, which is critical when considering soil microbial communities of high diversity. To overcome these limitations we used pyrosequencing and quantitative PCR (qPCR) of two genes (the V3 region of 16S rDNA and the amoA gene) to examine intra- and inter-treatment variability in the abundance and composition of microbial communities in the rhizosphere of soybean (C3) and maize (C4) grown in field conditions under ambient (~380 ppm) and elevated (~550 ppm) CO2 using FACE (free-air concentration enrichment) technology during the 2006 growing season in central Illinois. We specifically focused on archaeal communities because of their key role in nitrification (Leininger et al., 2006, Nature, 442, 806). The majority (>97%) of recovered sequences were from members of the phylum Crenarchaeota. Principle component analysis of sequence results from the V3 and amoA genes indicated significant (p<0.05) differences in the composition of rhizosphere archaeal communities between ambient and elevated CO2 beneath soybean, but not maize. qPCR suggested no significant difference in the abundance of archaea between treatments for soybean and maize. The lack of response of archaeal community composition beneath maize to elevated CO2 is consistent with relatively high

  11. Sequence Analysis and Comparative Study of the Protein Subunits of Archaeal RNase P

    Directory of Open Access Journals (Sweden)

    Manoj P. Samanta

    2016-04-01

    Full Text Available RNase P, a ribozyme-based ribonucleoprotein (RNP complex that catalyzes tRNA 5′-maturation, is ubiquitous in all domains of life, but the evolution of its protein components (RNase P proteins, RPPs is not well understood. Archaeal RPPs may provide clues on how the complex evolved from an ancient ribozyme to an RNP with multiple archaeal and eukaryotic (homologous RPPs, which are unrelated to the single bacterial RPP. Here, we analyzed the sequence and structure of archaeal RPPs from over 600 available genomes. All five RPPs are found in eight archaeal phyla, suggesting that these RPPs arose early in archaeal evolutionary history. The putative ancestral genomic loci of archaeal RPPs include genes encoding several members of ribosome, exosome, and proteasome complexes, which may indicate coevolution/coordinate regulation of RNase P with other core cellular machineries. Despite being ancient, RPPs generally lack sequence conservation compared to other universal proteins. By analyzing the relative frequency of residues at every position in the context of the high-resolution structures of each of the RPPs (either alone or as functional binary complexes, we suggest residues for mutational analysis that may help uncover structure-function relationships in RPPs.

  12. Sequence Analysis and Comparative Study of the Protein Subunits of Archaeal RNase P.

    Science.gov (United States)

    Samanta, Manoj P; Lai, Stella M; Daniels, Charles J; Gopalan, Venkat

    2016-01-01

    RNase P, a ribozyme-based ribonucleoprotein (RNP) complex that catalyzes tRNA 5'-maturation, is ubiquitous in all domains of life, but the evolution of its protein components (RNase P proteins, RPPs) is not well understood. Archaeal RPPs may provide clues on how the complex evolved from an ancient ribozyme to an RNP with multiple archaeal and eukaryotic (homologous) RPPs, which are unrelated to the single bacterial RPP. Here, we analyzed the sequence and structure of archaeal RPPs from over 600 available genomes. All five RPPs are found in eight archaeal phyla, suggesting that these RPPs arose early in archaeal evolutionary history. The putative ancestral genomic loci of archaeal RPPs include genes encoding several members of ribosome, exosome, and proteasome complexes, which may indicate coevolution/coordinate regulation of RNase P with other core cellular machineries. Despite being ancient, RPPs generally lack sequence conservation compared to other universal proteins. By analyzing the relative frequency of residues at every position in the context of the high-resolution structures of each of the RPPs (either alone or as functional binary complexes), we suggest residues for mutational analysis that may help uncover structure-function relationships in RPPs. PMID:27104580

  13. Sequence Analysis and Comparative Study of the Protein Subunits of Archaeal RNase P

    Science.gov (United States)

    Samanta, Manoj P.; Lai, Stella M.; Daniels, Charles J.; Gopalan, Venkat

    2016-01-01

    RNase P, a ribozyme-based ribonucleoprotein (RNP) complex that catalyzes tRNA 5′-maturation, is ubiquitous in all domains of life, but the evolution of its protein components (RNase P proteins, RPPs) is not well understood. Archaeal RPPs may provide clues on how the complex evolved from an ancient ribozyme to an RNP with multiple archaeal and eukaryotic (homologous) RPPs, which are unrelated to the single bacterial RPP. Here, we analyzed the sequence and structure of archaeal RPPs from over 600 available genomes. All five RPPs are found in eight archaeal phyla, suggesting that these RPPs arose early in archaeal evolutionary history. The putative ancestral genomic loci of archaeal RPPs include genes encoding several members of ribosome, exosome, and proteasome complexes, which may indicate coevolution/coordinate regulation of RNase P with other core cellular machineries. Despite being ancient, RPPs generally lack sequence conservation compared to other universal proteins. By analyzing the relative frequency of residues at every position in the context of the high-resolution structures of each of the RPPs (either alone or as functional binary complexes), we suggest residues for mutational analysis that may help uncover structure-function relationships in RPPs. PMID:27104580

  14. Comprehensive phylogenetic analysis of bacterial reverse transcriptases.

    Directory of Open Access Journals (Sweden)

    Nicolás Toro

    Full Text Available Much less is known about reverse transcriptases (RTs in prokaryotes than in eukaryotes, with most prokaryotic enzymes still uncharacterized. Two surveys involving BLAST searches for RT genes in prokaryotic genomes revealed the presence of large numbers of diverse, uncharacterized RTs and RT-like sequences. Here, using consistent annotation across all sequenced bacterial species from GenBank and other sources via RAST, available from the PATRIC (Pathogenic Resource Integration Center platform, we have compiled the data for currently annotated reverse transcriptases from completely sequenced bacterial genomes. RT sequences are broadly distributed across bacterial phyla, but green sulfur bacteria and cyanobacteria have the highest levels of RT sequence diversity (≤85% identity per genome. By contrast, phylum Actinobacteria, for which a large number of genomes have been sequenced, was found to have a low RT sequence diversity. Phylogenetic analyses revealed that bacterial RTs could be classified into 17 main groups: group II introns, retrons/retron-like RTs, diversity-generating retroelements (DGRs, Abi-like RTs, CRISPR-Cas-associated RTs, group II-like RTs (G2L, and 11 other groups of RTs of unknown function. Proteobacteria had the highest potential functional diversity, as they possessed most of the RT groups. Group II introns and DGRs were the most widely distributed RTs in bacterial phyla. Our results provide insights into bacterial RT phylogeny and the basis for an update of annotation systems based on sequence/domain homology.

  15. Enhanced abundance and diversity of ammonia-oxidizing Archaea in the Pearl River estuary

    Science.gov (United States)

    Xie, W.; Zhang, C. L.; Wang, P.; Zhou, X.; Guo, W.

    2014-12-01

    Thaumarchaeota are recently recognized as an important group of Archaea that can perform aerobic oxidation of ammonia in a wide range of environments. The goal of this study was to evaluate changes in abundance and diversity of planktonic ammonia-oxidizing Archaea (e.g., Thaumarchaeota) along a salinity gradient from the lower Pearl River to the northern South China Sea. Quantitative PCR and sequencing of total archaeal 16S rRNA gene and the archaeal amoA gene were performed on suspended particulate organic matter collected in different seasons from the freshwater to the ocean water. Total amoA gene copies and relative abundance of Thaumarchaeota all peaked in the estuary where salinity ranged between 4.5‰ and 26.7‰. The diversity of archaeal amoA gene was also highest in the estuary. Seasonality and SiO32- appear to be two major factors affecting the distribution of subclusters of archaeal amoA genes. For example, Nitrosopumilus subcluster 7.1 was most abundant in winter in fresh water, whereas Nitrososphaera were more abundant in summer. Samples collected from the area around Wanshan Island, which is located at the outermost part of the Pearl River estuary, had high abundance of unclassified archaeal amoA genes, suggesting some new groups of Thaumarchaeota might inhabit this water body. Overall, the high abundance and diversity of Thaumarchaeota in the Pearl River estuary may indicate enhanced role of AOA in nitrogen cycle in this dynamic ecosystem.

  16. Ultrafast Approximation for Phylogenetic Bootstrap

    NARCIS (Netherlands)

    Bui Quang Minh, [No Value; Nguyen, Thi; von Haeseler, Arndt

    2013-01-01

    Nonparametric bootstrap has been a widely used tool in phylogenetic analysis to assess the clade support of phylogenetic trees. However, with the rapidly growing amount of data, this task remains a computational bottleneck. Recently, approximation methods such as the RAxML rapid bootstrap (RBS) and

  17. Quartets and unrooted phylogenetic networks.

    Science.gov (United States)

    Gambette, Philippe; Berry, Vincent; Paul, Christophe

    2012-08-01

    Phylogenetic networks were introduced to describe evolution in the presence of exchanges of genetic material between coexisting species or individuals. Split networks in particular were introduced as a special kind of abstract network to visualize conflicts between phylogenetic trees which may correspond to such exchanges. More recently, methods were designed to reconstruct explicit phylogenetic networks (whose vertices can be interpreted as biological events) from triplet data. In this article, we link abstract and explicit networks through their combinatorial properties, by introducing the unrooted analog of level-k networks. In particular, we give an equivalence theorem between circular split systems and unrooted level-1 networks. We also show how to adapt to quartets some existing results on triplets, in order to reconstruct unrooted level-k phylogenetic networks. These results give an interesting perspective on the combinatorics of phylogenetic networks and also raise algorithmic and combinatorial questions. PMID:22809417

  18. Diversity and phylogenetic relationships of hemosporidian parasites in birds of Socorro Island, México, and their role in the re-introduction of the Socorro dove (Zenaida graysoni).

    Science.gov (United States)

    Carlson, Jenny S; Martínez-Gómez, Juan E; Valkiūnas, Gediminas; Loiseau, Claire; Bell, Douglas A; Sehgal, Ravinder N M

    2013-04-01

    The Socorro dove Zenaida graysoni , endemic to Socorro Island, was last reported in the wild in 1972. Fortunately, the species has been propagated in zoos in Europe and the United States, and plans are under way to re-introduce it to its native habitat. This will be the first known attempt to return a bird species extinct in the wild to its ancestral island. In order to assess the disease threats the Socorro dove may face, the avifauna of Socorro Island, with a specific focus on Socorro ground doves Columbina passerina socorroensis and mourning doves Zenaida macroura , as well as Socorro doves in captivity, were screened for blood parasites of the genera Plasmodium , Haemoproteus, Leucocytozoon, and Trypanosoma spp. We found Haemoproteus spp. in 17 (74%) of 23 Socorro ground doves, 23 (92%) of 25 mourning doves, and 3 (14%) of 21 northern mockingbirds; none of the other bird species showed infections. Here, we report the phylogenetic analysis of 19 distinct lineages of Haemoproteus spp. detected in birds of Socorro Island and compare their evolutionary relationships to parasites detected in the avifauna of the Galápagos Islands, continental Latin America, and Europe. Microscopic examination revealed 1 mourning dove infected with Plasmodium ( Haemamoeba ), thus underscoring the importance of using both PCR and microscopy when analyzing avian blood samples for hemosporidian parasites. The study confirms that the Socorro dove will most likely be exposed to Haemoproteus spp. that currently infect mourning doves and Socorro ground doves of Socorro Island. A monitoring program for both birds and vectors should be implemented to establish the prevalence of Plasmodium sp. and as a necessary conservation measure for critically endangered birds on the island. PMID:23043349

  19. A phylogenetic blueprint for a modern whale.

    Science.gov (United States)

    Gatesy, John; Geisler, Jonathan H; Chang, Joseph; Buell, Carl; Berta, Annalisa; Meredith, Robert W; Springer, Mark S; McGowen, Michael R

    2013-02-01

    The emergence of Cetacea in the Paleogene represents one of the most profound macroevolutionary transitions within Mammalia. The move from a terrestrial habitat to a committed aquatic lifestyle engendered wholesale changes in anatomy, physiology, and behavior. The results of this remarkable transformation are extant whales that include the largest, biggest brained, fastest swimming, loudest, deepest diving mammals, some of which can detect prey with a sophisticated echolocation system (Odontoceti - toothed whales), and others that batch feed using racks of baleen (Mysticeti - baleen whales). A broad-scale reconstruction of the evolutionary remodeling that culminated in extant cetaceans has not yet been based on integration of genomic and paleontological information. Here, we first place Cetacea relative to extant mammalian diversity, and assess the distribution of support among molecular datasets for relationships within Artiodactyla (even-toed ungulates, including Cetacea). We then merge trees derived from three large concatenations of molecular and fossil data to yield a composite hypothesis that encompasses many critical events in the evolutionary history of Cetacea. By combining diverse evidence, we infer a phylogenetic blueprint that outlines the stepwise evolutionary development of modern whales. This hypothesis represents a starting point for more detailed, comprehensive phylogenetic reconstructions in the future, and also highlights the synergistic interaction between modern (genomic) and traditional (morphological+paleontological) approaches that ultimately must be exploited to provide a rich understanding of evolutionary history across the entire tree of Life. PMID:23103570

  20. Soil bacterial and archaeal communities of the Stringer Creek Watershed in relation to soil moisture, chemistry, and gas fluxes

    Science.gov (United States)

    Jones, R. T.; Du, Z.; Riveros-Iregui, D.; Dore, J. E.; Emanuel, R. E.; McGlynn, B. L.; McDermott, T.; Li, X.

    2013-12-01

    The Stringer Creek watershed within the Tenderfoot Creek Experimental Forest (Montana) is a highly instrumented watershed with long-term hydrologic and gas flux measurements, and is an ideal study system to incorporate microbiological characterizations into landscape scale hydrological and biogeochemical studies. As a first attempt to determine how hydrological processes, soil chemistry, and gas fluxes are correlated with bacterial and archaeal lineages in soil, we collected soil samples across the watershed (July 9 - 11, 2012) and used barcoded high-throughput DNA sequencing to characterize the bacterial and archaeal communities. Soils were collected adjacent to gas well sites at 5 cm, 20 cm, and 50 cm depths, corresponding to the depths of the wells. Gas measurements included CO2, CH4, O2, and N2O; soil measurements included water content, % carbon, and % nitrogen. We analyzed 775,000 16S rRNA gene sequences from 28 soil samples. Relative abundances of certain microbial lineages or groups (e.g. methanotrophs, methanogens, Acidobacteria, Bacteroidetes, Firmicutes, Proteobacteria, etc.) varied significantly with CO2, CH4, and O2 concentrations. Furthermore, beta-diversity analyses showed that microbial community composition was significantly governed by water content, % nitrogen, and % carbon; community composition also significantly varied with CO2, CH4, and O2 concentrations. Together, our results suggest that soil environmental factors such as water content, % carbon, and % nitrogen affect microbial community composition, and that microbial community composition correlates with CO2, O2, and CH4 concentrations. Future work will focus on characterizing microbial communities across the entire summer season as soil conditions drastically change from fully saturated to very dry.

  1. Phylogenetic distribution of fungal sterols.

    Directory of Open Access Journals (Sweden)

    John D Weete

    Full Text Available BACKGROUND: Ergosterol has been considered the "fungal sterol" for almost 125 years; however, additional sterol data superimposed on a recent molecular phylogeny of kingdom Fungi reveals a different and more complex situation. METHODOLOGY/PRINCIPAL FINDINGS: The interpretation of sterol distribution data in a modern phylogenetic context indicates that there is a clear trend from cholesterol and other Delta(5 sterols in the earliest diverging fungal species to ergosterol in later diverging fungi. There are, however, deviations from this pattern in certain clades. Sterols of the diverse zoosporic and zygosporic forms exhibit structural diversity with cholesterol and 24-ethyl -Delta(5 sterols in zoosporic taxa, and 24-methyl sterols in zygosporic fungi. For example, each of the three monophyletic lineages of zygosporic fungi has distinctive major sterols, ergosterol in Mucorales, 22-dihydroergosterol in Dimargaritales, Harpellales, and Kickxellales (DHK clade, and 24-methyl cholesterol in Entomophthorales. Other departures from ergosterol as the dominant sterol include: 24-ethyl cholesterol in Glomeromycota, 24-ethyl cholest-7-enol and 24-ethyl-cholesta-7,24(28-dienol in rust fungi, brassicasterol in Taphrinales and hypogeous pezizalean species, and cholesterol in Pneumocystis. CONCLUSIONS/SIGNIFICANCE: Five dominant end products of sterol biosynthesis (cholesterol, ergosterol, 24-methyl cholesterol, 24-ethyl cholesterol, brassicasterol, and intermediates in the formation of 24-ethyl cholesterol, are major sterols in 175 species of Fungi. Although most fungi in the most speciose clades have ergosterol as a major sterol, sterols are more varied than currently understood, and their distribution supports certain clades of Fungi in current fungal phylogenies. In addition to the intellectual importance of understanding evolution of sterol synthesis in fungi, there is practical importance because certain antifungal drugs (e.g., azoles target reactions in

  2. CoBaltDB: Complete bacterial and archaeal orfeomes subcellular localization database and associated resources

    Directory of Open Access Journals (Sweden)

    Lucchetti-Miganeh Céline

    2010-03-01

    Full Text Available Abstract Background The functions of proteins are strongly related to their localization in cell compartments (for example the cytoplasm or membranes but the experimental determination of the sub-cellular localization of proteomes is laborious and expensive. A fast and low-cost alternative approach is in silico prediction, based on features of the protein primary sequences. However, biologists are confronted with a very large number of computational tools that use different methods that address various localization features with diverse specificities and sensitivities. As a result, exploiting these computer resources to predict protein localization accurately involves querying all tools and comparing every prediction output; this is a painstaking task. Therefore, we developed a comprehensive database, called CoBaltDB, that gathers all prediction outputs concerning complete prokaryotic proteomes. Description The current version of CoBaltDB integrates the results of 43 localization predictors for 784 complete bacterial and archaeal proteomes (2.548.292 proteins in total. CoBaltDB supplies a simple user-friendly interface for retrieving and exploring relevant information about predicted features (such as signal peptide cleavage sites and transmembrane segments. Data are organized into three work-sets ("specialized tools", "meta-tools" and "additional tools". The database can be queried using the organism name, a locus tag or a list of locus tags and may be browsed using numerous graphical and text displays. Conclusions With its new functionalities, CoBaltDB is a novel powerful platform that provides easy access to the results of multiple localization tools and support for predicting prokaryotic protein localizations with higher confidence than previously possible. CoBaltDB is available at http://www.umr6026.univ-rennes1.fr/english/home/research/basic/software/cobalten.

  3. Phylogenetic analysis of the Bifidobacterium genus using glycolysis enzyme sequences

    Directory of Open Access Journals (Sweden)

    Katelyn eBrandt

    2016-05-01

    Full Text Available Bifidobacteria are important members of the human gastrointestinal tract that promote the establishment of a healthy microbial consortium in the gut of infants. Recent studies have established that the Bifidobacterium genus is a polymorphic phylogenetic clade, which encompasses a diversity of species and subspecies that encode a broad range of proteins implicated in complex and non-digestible carbohydrate uptake and catabolism, ranging from human breast milk oligosaccharides, to plant fibers. Recent genomic studies have created a need to properly place Bifidobacterium species in a phylogenetic tree. Current approaches, based on core-genome analyses come at the cost of intensive sequencing and demanding analytical processes. Here, we propose a typing method based on sequences of glycolysis genes and the proteins they encode, to provide insights into diversity, typing, and phylogeny in this complex and broad genus. We show that glycolysis genes occur broadly in these genomes, to encode the machinery necessary for the biochemical spine of the cell, and provide a robust phylogenetic marker. Furthermore, glycolytic sequences-based trees are congruent with both the classical 16S rRNA phylogeny, and core genome-based strain clustering. Furthermore, these glycolysis markers can also be used to provide insights into the adaptive evolution of this genus, especially with regards to trends towards a high GC content. This streamlined method may open new avenues for phylogenetic studies on a broad scale, given the widespread occurrence of the glycolysis pathway in bacteria, and the diversity of the sequences they encode.

  4. Correlations between Archaeal Diversity and Geochemical Parameters in an Arsenic-Rich Hydrothermal System

    Science.gov (United States)

    Franks, M.; Omelon, C.; Engel, A. S.; Bennett, P.

    2009-04-01

    Characterizing microbial communities within their geochemical environment is useful for understanding microbial distribution and microbial adaptations to extreme physical and chemical conditions. The hydrothermal waters at El Tatio geyser field (ETGF) demonstrate extreme geochemical conditions, with discharge water from springs and geysers at local boiling temperature (85oC), arsenic concentrations of 0.5 mM, and inorganic carbon concentrations (DIC) as low as 0.2mM. Yet many of El Tatio's hundred plus hydrothermal features host extensive microbial mat communities. Recent work has shown correlations between the metabolic guilds of microorganisms present and variations in water chemistry. ETGF is a high-altitude hydrothermal basin with over 100 mapped hydrothermal features, located within a 30km2 area near the Chile-Bolivia border. The Na-Cl type waters have a circumneutral pH and contain abundant dissolved metals. Shallow runoff aprons extend tens of meters from some geyser features, where silica rapidly precipitates from cooling water. Thick mats, which appear microbial but consist primarily of silica, iron and arsenic mineral deposits, containing

  5. Bacterial and archaeal diversity in an iron-rich coastal hydrothermal field in Yamagawa, Kagoshima, Japan

    DEFF Research Database (Denmark)

    Kawaichi, Satoshi; Ito, Norihiro; Yoshida, Takashi;

    2013-01-01

    . The environmental settings of the coastal hydrothermal field were similar in some degree to those of deep-sea hydrothermal environments because of its emission of H2, CO2, and sulfide from the bottom of the hot spot. The results of clone analyses based on the 16S rRNA gene led us to speculate the...... presence of a chemo-synthetic microbial ecosystem, where chemolithoautotrophic thermophiles, primarily the bacterial order Aquificales, function as primary producers using H2 or sulfur compounds as their energy source and CO2 as their carbon source, and the organic compounds synthesized by them support the...... can also function as primary producing or nitrogen-fixing bacteria....

  6. Bacterial and Archaeal α-Amylases: Diversity and Amelioration of the Desirable Characteristics for Industrial Applications

    Science.gov (United States)

    Mehta, Deepika; Satyanarayana, Tulasi

    2016-01-01

    Industrial enzyme market has been projected to reach US$ 6.2 billion by 2020. Major reasons for continuous rise in the global sales of microbial enzymes are because of increase in the demand for consumer goods and biofuels. Among major industrial enzymes that find applications in baking, alcohol, detergent, and textile industries are α-amylases. These are produced by a variety of microbes, which randomly cleave α-1,4-glycosidic linkages in starch leading to the formation of limit dextrins. α-Amylases from different microbial sources vary in their properties, thus, suit specific applications. This review focuses on the native and recombinant α-amylases from bacteria and archaea, their production and the advancements in the molecular biology, protein engineering and structural studies, which aid in ameliorating their properties to suit the targeted industrial applications. PMID:27516755

  7. Influence of DNA isolation method on the investigation of archaeal diversity and abundance in biogas plants.

    Science.gov (United States)

    Theiss, Juliane; Rother, Michael; Röske, Kerstin

    2016-09-01

    Various methods are available for DNA isolation from environmental samples. Because the chemical and biological composition of samples such as soil, sludge, or plant material is different, the effectiveness of DNA isolation can vary depending on the method applied and thus, have a substantial effect on the results of downstream analysis of the microbial community. Although the process of biogas formation is being intensely investigated, a systematic evaluation of kits for DNA isolation from material of biogas plants is still lacking. Since no DNA isolation kit specifically tailored for DNA isolation from sludge of biogas plants is available, this study compares five commercially available kits regarding their influence on downstream analyses such denaturing gradient gel electrophoresis (DGGE) and quantitative real-time PCR (qPCR). The results show that not all kits are equally suited for the DNA isolation from samples of different biogas plants, but highly reproducible DGGE fingerprints as well as qPCR results across the tested samples from biogas reactors using different substrate compositions could be produced using selected kits. PMID:27089887

  8. Quantum Simulation of Phylogenetic Trees

    OpenAIRE

    Ellinas, Demosthenes; Jarvis, Peter

    2011-01-01

    Quantum simulations constructing probability tensors of biological multi-taxa in phylogenetic trees are proposed, in terms of positive trace preserving maps, describing evolving systems of quantum walks with multiple walkers. Basic phylogenetic models applying on trees of various topologies are simulated following appropriate decoherent quantum circuits. Quantum simulations of statistical inference for aligned sequences of biological characters are provided in terms of a quantum pruning map o...

  9. Phylogeny and palm diversity across scales

    DEFF Research Database (Denmark)

    Eiserhardt, Wolf L.; Svenning, J.-C.; Baker, William J.;

    Palms lend themselves to exploring approaches at the intersection of ecology and phylogenetics. They are taxonomically diverse, often key functional components of ecosystems, and form complex assemblages of different co-existing life-forms. Recent advances in palm phylogenetics, including a dated...

  10. Archaeal and Bacterial Communities Associated with the Surface Mucus of Caribbean Corals Differ in Their Degree of Host Specificity and Community Turnover Over Reefs

    NARCIS (Netherlands)

    Frade, P.R.; Roll, K.; Bergauer, K.; Herndl, G.

    2016-01-01

    Comparative studies on the distribution of archaeal versus bacterial communities associatedwith the surface mucus layer of corals have rarely taken place. It has thereforeremained enigmatic whether mucus-associated archaeal and bacterial communities exhibita similar specificity towards coral hosts a

  11. Quantification of bacterial and archaeal symbionts in high and low microbial abundance sponges using real-time PCR

    KAUST Repository

    Bayer, Kristina

    2014-07-09

    In spite of considerable insights into the microbial diversity of marine sponges, quantitative information on microbial abundances and community composition remains scarce. Here, we established qPCR assays for the specific quantification of four bacterial phyla of representative sponge symbionts as well as the kingdoms Eubacteria and Archaea. We could show that the 16S rRNA gene numbers of Archaea, Chloroflexi, and the candidate phylum Poribacteria were 4-6 orders of magnitude higher in high microbial abundance (HMA) than in low microbial abundance (LMA) sponges and that actinobacterial 16S rRNA gene numbers were 1-2 orders higher in HMA over LMA sponges, while those for Cyanobacteria were stable between HMA and LMA sponges. Fluorescence in situ hybridization of Aplysina aerophoba tissue sections confirmed the numerical dominance of Chloroflexi, which was followed by Poribacteria. Archaeal and actinobacterial cells were detected in much lower numbers. By use of fluorescence-activated cell sorting as a primer- and probe-independent approach, the dominance of Chloroflexi, Proteobacteria, and Poribacteria in A. aerophoba was confirmed. Our study provides new quantitative insights into the microbiology of sponges and contributes to a better understanding of the HMA/LMA dichotomy. The authors quantified sponge symbionts in eight sponge species from three different locations by real time PCR targetting 16S rRNA genes. Additionally, FISH was performed and diversity and abundance of singularized microbial symbionts from Aplysina aerophoba was determined for a comprehensive quantification work. © 2014 Federation of European Microbiological Societies.

  12. Phylogenetically distinct phylotypes modulate nitrification in a paddy soil.

    Science.gov (United States)

    Zhao, Jun; Wang, Baozhan; Jia, Zhongjun

    2015-05-01

    Paddy fields represent a unique ecosystem in which regular flooding occurs, allowing for rice cultivation. However, the taxonomic identity of the microbial functional guilds that catalyze soil nitrification remains poorly understood. In this study, we provide molecular evidence for distinctly different phylotypes of nitrifying communities in a neutral paddy soil using high-throughput pyrosequencing and DNA-based stable isotope probing (SIP). Following urea addition, the levels of soil nitrate increased significantly, accompanied by an increase in the abundance of the bacterial and archaeal amoA gene in microcosms subjected to SIP (SIP microcosms) during a 56-day incubation period. High-throughput fingerprints of the total 16S rRNA genes in SIP microcosms indicated that nitrification activity positively correlated with the abundance of Nitrosospira-like ammonia-oxidizing bacteria (AOB), soil group 1.1b-like ammonia-oxidizing archaea (AOA), and Nitrospira-like nitrite-oxidizing bacteria (NOB). Pyrosequencing of 13C-labeled DNA further revealed that 13CO2 was assimilated by these functional groups to a much greater extent than by marine group 1.1a-associated AOA and Nitrobacter-like NOB. Phylogenetic analysis demonstrated that active AOB communities were closely affiliated with Nitrosospira sp. strain L115 and the Nitrosospira multiformis lineage and that the 13C-labeled AOA were related to phylogenetically distinct groups, including the moderately thermophilic "Candidatus Nitrososphaera gargensis," uncultured fosmid 29i4, and acidophilic "Candidatus Nitrosotalea devanaterra" lineages. These results suggest that a wide variety of microorganisms were involved in soil nitrification, implying physiological diversification of soil nitrifying communities that are constantly exposed to environmental fluctuations in paddy fields. PMID:25724959

  13. Liquid but Durable: Molecular Dynamics Simulations Explain the Unique Properties of Archaeal-Like Membranes

    Science.gov (United States)

    Chugunov, Anton O.; Volynsky, Pavel E.; Krylov, Nikolay A.; Boldyrev, Ivan A.; Efremov, Roman G.

    2014-12-01

    Archaeal plasma membranes appear to be extremely durable and almost impermeable to water and ions, in contrast to the membranes of Bacteria and Eucaryota. Additionally, they remain liquid within a temperature range of 0-100°C. These are the properties that have most likely determined the evolutionary fate of Archaea, and it may be possible for bionanotechnology to adopt these from nature. In this work, we use molecular dynamics simulations to assess at the atomistic level the structure and dynamics of a series of model archaeal membranes with lipids that have tetraether chemical nature and ``branched'' hydrophobic tails. We conclude that the branched structure defines dense packing and low water permeability of archaeal-like membranes, while at the same time ensuring a liquid-crystalline state, which is vital for living cells. This makes tetraether lipid systems promising in bionanotechnology and material science, namely for design of new and unique membrane nanosystems.

  14. The phylogenetic structure of plant-pollinator networks increases with habitat size and isolation.

    Science.gov (United States)

    Aizen, Marcelo A; Gleiser, Gabriela; Sabatino, Malena; Gilarranz, Luis J; Bascompte, Jordi; Verdú, Miguel

    2016-01-01

    Similarity among species in traits related to ecological interactions is frequently associated with common ancestry. Thus, closely related species usually interact with ecologically similar partners, which can be reinforced by diverse co-evolutionary processes. The effect of habitat fragmentation on the phylogenetic signal in interspecific interactions and correspondence between plant and animal phylogenies is, however, unknown. Here, we address to what extent phylogenetic signal and co-phylogenetic congruence of plant-animal interactions depend on habitat size and isolation by analysing the phylogenetic structure of 12 pollination webs from isolated Pampean hills. Phylogenetic signal in interspecific interactions differed among webs, being stronger for flower-visiting insects than plants. Phylogenetic signal and overall co-phylogenetic congruence increased independently with hill size and isolation. We propose that habitat fragmentation would erode the phylogenetic structure of interaction webs. A decrease in phylogenetic signal and co-phylogenetic correspondence in plant-pollinator interactions could be associated with less reliable mutualism and erratic co-evolutionary change. PMID:26493295

  15. Phylogenetic signals in the climatic niches of the world's amphibians

    DEFF Research Database (Denmark)

    Hof, Christian; Rahbek, Carsten; Araújo, Miguel B.

    2010-01-01

    The question of whether closely related species share similar ecological requirements has attracted increasing attention, because of its importance for understanding global diversity gradients and the impacts of climate change on species distributions. In fact, the assumption that related species...... are also ecologically similar has often been made, although the prevalence of such a phylogenetic signal in ecological niches remains heavily debated. Here, we provide a global analysis of phylogenetic niche relatedness for the world's amphibians. In particular, we assess which proportion of the...... variance in the realised climatic niches is explained on higher taxonomic levels, and whether the climatic niches of species within a given taxonomic group are more similar than between taxonomic groups. We found evidence for phylogenetic signals in realised climatic niches although the strength of the...

  16. Phylogenetic analysis of Ostreococcus virus sequences from the Patagonian Coast.

    Science.gov (United States)

    Manrique, Julieta M; Calvo, Andrea Y; Jones, Leandro R

    2012-10-01

    A phylogenetic analysis of new Ostreococcus virus (OV) sequences from the Patagonian Coast, Argentina, and homologous sequences from public databases was performed. This analysis showed that the Patagonian sequences represented a divergent viral clade and that the rest of OV sequences analyzed here were clustered into six additional phylogenetic groups. Analyses of 18S gene libraries supported a close relationship of the Patagonian Ostreococcus host with clade A sequences described elsewhere, corroborating previous studies indicating that clade A strains are ubiquitous. Besides the Patagonian OV sequences, several phylogenetic groupings were linked to particular geographic locations, suggesting a role for allopatric cladogenesis in viral diversification. However, and in agreement with previous observations, other viral lineages included sequences with diverse geographic origins. These findings, together with analyses of ancestral trait trajectories performed here, are consistent with an evolutionary dynamics in which geographical isolation has a role in OV diversification but can be followed by rapid dispersion to remote places. PMID:22674355

  17. Charles Darwin, beetles and phylogenetics

    Science.gov (United States)

    Beutel, Rolf G.; Friedrich, Frank; Leschen, Richard A. B.

    2009-11-01

    Here, we review Charles Darwin’s relation to beetles and developments in coleopteran systematics in the last two centuries. Darwin was an enthusiastic beetle collector. He used beetles to illustrate different evolutionary phenomena in his major works, and astonishingly, an entire sub-chapter is dedicated to beetles in “The Descent of Man”. During his voyage on the Beagle, Darwin was impressed by the high diversity of beetles in the tropics, and he remarked that, to his surprise, the majority of species were small and inconspicuous. However, despite his obvious interest in the group, he did not get involved in beetle taxonomy, and his theoretical work had little immediate impact on beetle classification. The development of taxonomy and classification in the late nineteenth and earlier twentieth century was mainly characterised by the exploration of new character systems (e.g. larval features and wing venation). In the mid-twentieth century, Hennig’s new methodology to group lineages by derived characters revolutionised systematics of Coleoptera and other organisms. As envisioned by Darwin and Ernst Haeckel, the new Hennigian approach enabled systematists to establish classifications truly reflecting evolution. Roy A. Crowson and Howard E. Hinton, who both made tremendous contributions to coleopterology, had an ambivalent attitude towards the Hennigian ideas. The Mickoleit school combined detailed anatomical work with a classical Hennigian character evaluation, with stepwise tree building, comparatively few characters and a priori polarity assessment without explicit use of the outgroup comparison method. The rise of cladistic methods in the 1970s had a strong impact on beetle systematics. Cladistic computer programs facilitated parsimony analyses of large data matrices, mostly morphological characters not requiring detailed anatomical investigations. Molecular studies on beetle phylogeny started in the 1990s with modest taxon sampling and limited DNA data

  18. Specific impacts of beech and Norway spruce on the structure and diversity of the rhizosphere and soil microbial communities.

    Science.gov (United States)

    Uroz, S; Oger, P; Tisserand, E; Cébron, A; Turpault, M-P; Buée, M; De Boer, W; Leveau, J H J; Frey-Klett, P

    2016-01-01

    The impacts of plant species on the microbial communities and physico-chemical characteristics of soil are well documented for many herbs, grasses and legumes but much less so for tree species. Here, we investigate by rRNA and ITS amplicon sequencing the diversity of microorganisms from the three domains of life (Archaea, Bacteria and Eukaryota:Fungi) in soil samples taken from the forest experimental site of Breuil-Chenue (France). We discovered significant differences in the abundance, composition and structure of the microbial communities associated with two phylogenetically distant tree species of the same age, deciduous European beech (Fagus sylvatica) and coniferous Norway spruce (Picea abies Karst), planted in the same soil. Our results suggest a significant effect of tree species on soil microbiota though in different ways for each of the three microbial groups. Fungal and archaeal community structures and compositions are mainly determined according to tree species, whereas bacterial communities differ to a great degree between rhizosphere and bulk soils, regardless of the tree species. These results were confirmed by quantitative PCR, which revealed significant enrichment of specific bacterial genera, such as Burkholderia and Collimonas, known for their ability to weather minerals within the tree root vicinity. PMID:27302652

  19. Population and diversity of ammonia-oxidizing archaea and bacteria in a pollutants' receiving area in Hangzhou Bay.

    Science.gov (United States)

    Zhang, Yan; Chen, Lujun; Sun, Renhua; Dai, Tianjiao; Tian, Jinping; Zheng, Wei; Wen, Donghui

    2016-07-01

    The community structure of ammonia-oxidizing microorganisms is sensitive to various environmental factors, including pollutions. In this study, real-time PCR and 454 pyrosequencing were adopted to investigate the population and diversity of ammonia-oxidizing archaea (AOA) and bacteria (AOB) temporally and spatially in the sediments of an industrial effluent receiving area in the Qiantang River's estuary, Hangzhou Bay. The abundances of AOA and AOB amoA genes fluctuated in 10(5)-10(7) gene copies per gram of sediment; the ratio of AOA amoA/AOB amoA ranged in 0.39-5.52. The AOA amoA/archaeal 16S rRNA, AOB amoA/bacterial 16S rRNA, and AOA amoA/AOB amoA were found to positively correlate with NH4 (+)-N concentration of the seawater. Nitrosopumilus cluster and Nitrosomonas-like cluster were the dominant AOA and AOB, respectively. The community structures of both AOA and AOB in the sediments exhibited significant seasonal differences rather than spatial changes in the effluent receiving area. The phylogenetic distribution of AOB in this area was consistent with the wastewater treatment plants (WWTPs) discharging the effluent but differed from the Qiantang River and other estuaries, which might be an outcome of long-term effluent discharge. PMID:26960319

  20. 西菲律宾海比科尔陆架深海沉积物古菌多样性研究%The diversity of archaea in deep-sea sediments from the West Philippine Sea Bicol shelf

    Institute of Scientific and Technical Information of China (English)

    格根塔娜; 萨仁高娃; 于心科; 李铁刚; 周伟光

    2011-01-01

    The archaeal diversity and phylogenesis of the sediments samples from the Bicol shelf of the West Philippine Sea for the West Pacific Ocean were analyzed by the 16S rRNA gene clone library method. Totally 465 cloning sequences were obtained and divided into 63 OTUs. Phylogenetic analysis showed that the archaeal sequences were from Crenarchaeota and Euryarchaeota. The majority of the archaeal phylotypes were Marine Benthic Group B (MBGB), Marine Group I (MGI), Miscellaneous Crenarchaeotic Group (MCG), and Marine Benthic Group D. A few sequences fell into Marine Hydrothermal Vent Group (MHVG). The results indicated that the sediment samples of five different layers contained only five groups of archaea. Achaeal community diversity was low, and dominant archaea had some differences in each layers.%通过构建16S rRNA 基因文库, 对西太平洋西菲律宾海东板比科尔陆架5 个不同层位沉积物样品中的古菌的多样性进行了研究, 并获得了465 个有效克隆63 个OTUs (Operational Taxonomic Units)。通过16S rRNA 序列与GenBank 已知序列的同源性比较及构建系统进化树的结果显示, 古菌序列分别来自泉古菌(Crenarchaeota)和广古菌(Euryarchaeota), 以Marine Benthic Group B(MBGB)、Marine GroupI(MGI)、Miscellaneous Crenarchaeotic Group(MCG)和Marine Benthic Group D(MBGD)为主。少量序列为Marine Hydrothermal Vent Group(MHVG)。研究结果表明, 该垂直分布的5 个不同层位的沉积物样品仅有5 个古菌类群, 古菌群落多样性并不高, 且5 个层位中的优势古菌类群稍有差异。研究结果揭示了比科尔陆架深海古菌垂向分布特征, 为今后大范围自然海区古菌生态学研究提供科学参考。

  1. Exploring the biotechnologial applications in the archaeal domain Explorando as aplicações biotecnológicas do domínio archaea

    Directory of Open Access Journals (Sweden)

    S.M.C. Alquéres

    2007-09-01

    Full Text Available Archaea represent a considerable fraction of the prokaryotic world in marine and terrestrial ecosystems, indicating that organisms from this domain might have a large impact on global energy cycles. The extremophilic nature of many archaea has stimulated intense efforts to understand the physiological adaptations for living in extreme environments. Their unusual properties make them a potentially valuable resource in the development of novel biotechnological processes and industrial applications as new pharmaceuticals, cosmetics, nutritional supplements, molecular probes, enzymes, and fine chemicals. In the present mini-review, we show and discuss some exclusive characteristics of Archaea domain and the current knowledge about the biotechnological uses of the archaeal enzymes. The topics are: archaeal characteristics, phylogenetic division, biotechnological applications, isolation and cultivation of new microbes, achievements in genomics, and metagenomic.As arqueas representam uma considerável fração dos procariotos nos ecossistemas marinhos e terrestes, indicando que estes organismos devem possuir um grande impacto nos ciclos energéticos. A natureza extremofílica de muitas arqueas tem estimulado intensos esforços para compreender sua adaptação fisiológica a ambientes extremos. Suas propriedades incomus as tornam uma fonte valiosa no desenvolvimento de novos processos biotecnológicos e aplicações industriais como novos fármacos, cosméticos, suplementos nutricionais, sondas moleculares, enzimas e reagentes. Na presente mini-revisão, mostramos e discutimos algumas de suas características exclusivas correlacionando-as com seu potencial biotecnológico e aplicação industrial. Os tópicos são: características das arqueas, divisão filogenética, aplicações biotecnológicas, isolamento e cultivo de novos microrganismos, genoma e metagenoma.

  2. Abundance and diversity of ammonia-oxidizing archaea in response to various habitats in Pearl River Delta of China, a subtropical maritime zone

    Institute of Scientific and Technical Information of China (English)

    Zhixin Li; Wenbiao Jin; Zhaoyun Liang; Yangyang Yue; Junhong Lv

    2013-01-01

    Ammonia-oxidizing archaea (AOA) are widely considered key to ammonia oxidation in various environments.However,little work has been conducted to simultaneously investigate the abundance and diversity of AOA as well as correlations between archaeal amoA genotypes and environmental parameters of different ecosystems at one district.To understand the abundance,diversity,and distribution of AOA in Pearl River Delta of China in response to various habitats,the archaeal amoA genes in soil,marine,river,lake,hot spring and wastewater treatment plant (WWTP) samples were investigated using real-time fluorescent quantitative PCR and clone libraries.Our analyses indicated that the diversity of AOA in various habitats was different and could be clustered into five major clades,i.e.,estuary sediment,marine water/sediment,soil,hot spring and Cluster 1.Phylogenetic analyses revealed that the structure of AOA communities in similar ecological habitats exhibited strong relation.The canonical correspondence method indicated that the AOA community structure was strongly correlated to temperature,pH,total organic carbon,total nitrogen and dissolved oxygen variables.Assessing AOA amoA gene copy numbers,ranging from 6.84 × 106 to 9.45 × 107 copies/g in dry soil/sediment,and 6.06 × 106 to 2.41 × 107 copies/L in water samples,were higher than ammonia-oxidizing bacteria (AOB) by 1-2 orders of magnitude.However,AOA amoA copy numbers were much lower than AOB in WWTP activated sludge samples.Overall,these studies suggested that AOA may be a major contributor to ammonia oxidation in natural habitats but play a minor role in highly aerated activated sludge.The result also showed the ratio of AOA to AOB amoA gene abundance was positively correlated with temperature and less correlated with other environmental parameters.New data from our study provide increasing evidence for the relative abundance and diversity of ammonia-oxidizing archaea in the global nitrogen cycle.

  3. Robust identification of noncoding RNA from transcriptomes requires phylogenetically-informed sampling.

    Directory of Open Access Journals (Sweden)

    Stinus Lindgreen

    2014-10-01

    Full Text Available Noncoding RNAs are integral to a wide range of biological processes, including translation, gene regulation, host-pathogen interactions and environmental sensing. While genomics is now a mature field, our capacity to identify noncoding RNA elements in bacterial and archaeal genomes is hampered by the difficulty of de novo identification. The emergence of new technologies for characterizing transcriptome outputs, notably RNA-seq, are improving noncoding RNA identification and expression quantification. However, a major challenge is to robustly distinguish functional outputs from transcriptional noise. To establish whether annotation of existing transcriptome data has effectively captured all functional outputs, we analysed over 400 publicly available RNA-seq datasets spanning 37 different Archaea and Bacteria. Using comparative tools, we identify close to a thousand highly-expressed candidate noncoding RNAs. However, our analyses reveal that capacity to identify noncoding RNA outputs is strongly dependent on phylogenetic sampling. Surprisingly, and in stark contrast to protein-coding genes, the phylogenetic window for effective use of comparative methods is perversely narrow: aggregating public datasets only produced one phylogenetic cluster where these tools could be used to robustly separate unannotated noncoding RNAs from a null hypothesis of transcriptional noise. Our results show that for the full potential of transcriptomics data to be realized, a change in experimental design is paramount: effective transcriptomics requires phylogeny-aware sampling.

  4. Assembly and phylogenetic structure of Neotropical palm communities

    DEFF Research Database (Denmark)

    Eiserhardt, Wolf L.; Svenning, J.-C.; Balslev, Henrik

    Diversity, composition and dynamics of Neotropical palm communities are receiving an increasing amount of attention due to their economic importance, but also because their high species richness and functional diversity render them valuable model systems for overall forest biodiversity. However, to...... better understand these palm communities, it is crucial to gain insight into the mechanisms responsible for their assembly. These can be dispersal limitation, environmental filtering, or biotic interactions. If the degree of niche conservatism is known for a group of organisms, patterns of community...... phylogenetic structure can be directly traced back to mechanisms of community assembly. We aim to examine this for Neotropical palm communities. Phylogenetic structure will be inferred on different spatial scales and for different community definitions (plot-based and environment-based). To overcome an...

  5. Phylogenetic analysis of vitamin B12-related metabolism in Mycobacterium tuberculosis

    OpenAIRE

    Young, Douglas B.; Comas, Iñaki; de Carvalho, Luiz P. S.

    2015-01-01

    Comparison of genome sequences from clinical isolates of Mycobacterium tuberculosis with phylogenetically-related pathogens Mycobacterium marinum, Mycobacterium kansasii, and Mycobacterium leprae reveals diversity amongst genes associated with vitamin B12-related metabolism. Diversity is generated by gene deletion events, differential acquisition of genes by horizontal transfer, and single nucleotide polymorphisms (SNPs) with predicted impact on protein function and transcriptional regulation...

  6. Implementing a cumulative supermatrix approach for a comprehensive phylogenetic study of the Teloschistales (Pezizomycotina, Ascomycota)

    DEFF Research Database (Denmark)

    Gaya, Ester; Högnabba, Filip; Holguin, Ángela;

    2012-01-01

    The resolution of the phylogenetic relationships within the order Teloschistales (Ascomycota, lichen-forming-fungi), with nearly 2000 known species and outstanding phenotypic diversity, has been hindered by the limitation in the resolving power that single-locus or two-locus phylogenetic studies...... center of diversity – the Megalosporaceae – which is sister to the mainly rock-inhabiting, cosmopolitan, and species rich Teloschistaceae, with a diversity of growth habits ranging from crustose to fruticose. Our results confirm the use of a cumulative supermatrix approach as a viable method to generate...

  7. Identification of archaeal proteins that affect the exosome function in vitro

    Directory of Open Access Journals (Sweden)

    Palhano Fernando L

    2010-05-01

    Full Text Available Abstract Background The archaeal exosome is formed by a hexameric RNase PH ring and three RNA binding subunits and has been shown to bind and degrade RNA in vitro. Despite extensive studies on the eukaryotic exosome and on the proteins interacting with this complex, little information is yet available on the identification and function of archaeal exosome regulatory factors. Results Here, we show that the proteins PaSBDS and PaNip7, which bind preferentially to poly-A and AU-rich RNAs, respectively, affect the Pyrococcus abyssi exosome activity in vitro. PaSBDS inhibits slightly degradation of a poly-rA substrate, while PaNip7 strongly inhibits the degradation of poly-A and poly-AU by the exosome. The exosome inhibition by PaNip7 appears to depend at least partially on its interaction with RNA, since mutants of PaNip7 that no longer bind RNA, inhibit the exosome less strongly. We also show that FITC-labeled PaNip7 associates with the exosome in the absence of substrate RNA. Conclusions Given the high structural homology between the archaeal and eukaryotic proteins, the effect of archaeal Nip7 and SBDS on the exosome provides a model for an evolutionarily conserved exosome control mechanism.

  8. The effect of maturity and depositional redox conditions on archaeal tetraether lipid palaeothermometry

    NARCIS (Netherlands)

    Sinninghe Damsté, J.S.; Schouten, S.; Hopmans, E.C.

    2004-01-01

    Recently we proposed a new organic sea surface temperature proxy, TEX86, based on the distribution of archaeal tetraether lipids. Here, we have examined the effect of oxic degradation and maturity on this new temperature proxy. Our results show that oxic degradation does not appear to affect the TEX

  9. Abiotic Factors Shape Microbial Diversity in Sonoran Desert Soils

    OpenAIRE

    Andrew, David R.; Fitak, Robert R.; Munguia-Vega, Adrian; Racolta, Adriana; Martinson, Vincent G.; Dontsova, Katerina

    2012-01-01

    High-throughput, culture-independent surveys of bacterial and archaeal communities in soil have illuminated the importance of both edaphic and biotic influences on microbial diversity, yet few studies compare the relative importance of these factors. Here, we employ multiplexed pyrosequencing of the 16S rRNA gene to examine soil- and cactus-associated rhizosphere microbial communities of the Sonoran Desert and the artificial desert biome of the Biosphere2 research facility. The results of our...

  10. Phylogenetic clustering among aggressive competitors: evidence from odonate assemblages along a riverine gradient.

    Science.gov (United States)

    Saito, Victor S; Valente-Neto, Francisco; Rodrigues, Marciel Elio; de Oliveira Roque, Fabio; Siqueira, Tadeu

    2016-09-01

    Studies on phylogenetic community ecology usually infer habitat filtering when communities are phylogenetically clustered or competitive exclusion when communities are overdispersed. This logic is based on strong competition and niche similarity among closely related species-a less common phenomenon than previously expected. Dragonflies and damselflies are good models for testing predictions based on this logic because they behave aggressively towards related species due to mistaken identification of conspecifics. This behavior may drive communities toward phylogenetic overdispersion if closely related species frequently exclude each other. However, phylogenetically clustered communities could also be observed if habitat filtering and/or competitive asymmetry among distantly related species are major drivers of community assembling. We investigated the phylogenetic structure of odonate assemblages in central Brazil in a watershed characterized by variations in stream width, vegetation cover, aquatic vegetation, and luminosity. We observed general clustering in communities according to two indices of phylogenetic structure. Phylogenetic beta diversity coupled with Mantel tests and RLQ analysis evidenced a correlation between the riverine gradient and phylogenetic structure. Larger rivers with aquatic vegetation were characterized by anisopterans, while most zygopterans stayed in small and shaded streams. These results indicate niche conservatism in Odonata habitat occupancy, and that the environment is a major influence on the phylogenetic structure of these communities. We suggest that this is due to clade-specific ecophysiological requirements, and because closely related species may also have competitive advantages and dominate certain preferred habitats. PMID:27160426

  11. Effects of species’ similarity and dominance on the functional and phylogenetic structure of a plant meta-community

    OpenAIRE

    Chalmandrier, L.; Münkemüller, T.; Lavergne, S.; Thuiller, W.

    2015-01-01

    Different assembly processes drive the spatial structure of meta-communities (β-diversity). Recently, functional and phylogenetic diversities have been suggested as indicators of these assembly processes. Assuming that diversity is a good proxy for niche overlap, high β-diversity along environmental gradients should be the result of environmental filtering while low β-diversity should stem from competitive interactions. So far studies trying to disentangle the relative importance of these ass...

  12. Impact of lowland rainforest transformation on diversity and composition of soil prokaryotic communities in Sumatra (Indonesia

    Directory of Open Access Journals (Sweden)

    Dominik eSchneider

    2015-12-01

    Full Text Available Prokaryotes are the most abundant and diverse group of microorganisms in soil and mediate virtually all biogeochemical cycles in terrestrial ecosystems. Thereby, they influence aboveground plant productivity and diversity. In this study, the impact of rainforest transformation to intensively managed cash crop systems on soil prokaryotic communities was investigated. The studied managed land use system comprised rubber agroforests (jungle rubber, rubber plantation and oil plantations within two Indonesian landscapes Bukit Duabelas and Harapan. Soil prokaryotic community composition and diversity were assessed by pyrotag sequencing of bacterial and archaeal 16S rRNA genes. The curated dataset contained 20,494 bacterial and 1,762 archaeal Operational Taxonomic Units at species level (97% genetic identity. Analysis revealed changes in indigenous taxon-specific patterns of soil prokaryotic communities accompanying lowland rainforest transformation to jungle rubber, and intensively managed rubber and oil palm plantations. Distinct clustering of the rainforest soil communities indicated that these are different from the communities in the studied managed land use systems. The predominant bacterial taxa in all investigated soils were Acidobacteria, Actinobacteria, Alphaproteobacteria, Betaproteobacteria, and Gammaproteobacteria. Overall, the bacterial community shifted from proteobacterial groups in rainforest soils to Acidobacteria in managed soils. The archaeal soil communities were mainly represented by Thaumarchaeota and Euryarchaeota. Members of the Terrestrial Group and South African Gold Mine Group 1 (Thaumarchaeota dominated in the rainforest and members of Thermoplasmata in the managed land use systems. The alpha and beta diversity of the soil prokaryotic communities was higher in managed land use systems than in rainforest. In the case of bacteria, this was related to soil characteristics such as pH value, exchangeable Ca and Fe content, C to

  13. Landscape patterns in rainforest phylogenetic signal: isolated islands of refugia or structured continental distributions?

    Directory of Open Access Journals (Sweden)

    Robert M Kooyman

    Full Text Available OBJECTIVES: Identify patterns of change in species distributions, diversity, concentrations of evolutionary history, and assembly of Australian rainforests. METHODS: We used the distribution records of all known rainforest woody species in Australia across their full continental extent. These were analysed using measures of species richness, phylogenetic diversity (PD, phylogenetic endemism (PE and phylogenetic structure (net relatedness index; NRI. Phylogenetic structure was assessed using both continental and regional species pools. To test the influence of growth-form, freestanding and climbing plants were analysed independently, and in combination. RESULTS: Species richness decreased along two generally orthogonal continental axes, corresponding with wet to seasonally dry and tropical to temperate habitats. The PE analyses identified four main areas of substantially restricted phylogenetic diversity, including parts of Cape York, Wet Tropics, Border Ranges, and Tasmania. The continental pool NRI results showed evenness (species less related than expected by chance in groups of grid cells in coastally aligned areas of species rich tropical and sub-tropical rainforest, and in low diversity moist forest areas in the south-east of the Great Dividing Range and in Tasmania. Monsoon and drier vine forests, and moist forests inland from upland refugia showed phylogenetic clustering, reflecting lower diversity and more relatedness. Signals for evenness in Tasmania and clustering in northern monsoon forests weakened in analyses using regional species pools. For climbing plants, values for NRI by grid cell showed strong spatial structuring, with high diversity and PE concentrated in moist tropical and subtropical regions. CONCLUSIONS/SIGNIFICANCE: Concentrations of rainforest evolutionary history (phylo-diversity were patchily distributed within a continuum of species distributions. Contrasting with previous concepts of rainforest community

  14. Differential response of archaeal groups to land use change in an acidic red soil.

    Science.gov (United States)

    Shen, Ju-Pei; Cao, Peng; Hu, Hang-Wei; He, Ji-Zheng

    2013-09-01

    Land use management, one of the most important aspects of anthropogenic disturbance to terrestrial ecosystems, has exerted overriding impacts on soil biogeochemical cycling and inhabitant microorganisms. However, the knowledge concerning response of different archaeal groups to long-term land use changes is still limited in terrestrial environments. Here we used quantitative polymerase chain reaction (qPCR) and denaturing gradient gel electrophoresis (DGGE) approaches to investigate the response of archaeal communities to four different land use practices, i.e. cropland, pine forest, restoration land and degradation land. qPCR analyses showed that expression of the archaeal amoA gene responds more sensitively to changes of land use. In particular, we observed, occurring at significantly lower numbers of archaeal amoA genes in degradation land samples, while the abundance of total archaea and Group 1.1c based on 16S rRNA gene copy numbers remained constant among the different treatments examined. Soil nitrate content is significantly correlated with archaeal amoA gene abundance, but not their bacterial counterparts. The percentage of archaea among total prokaryote communities increases with increasing depth, but has no significant relationship with total carbon, total nitrogen or pH. Soil pH was significantly correlated with total bacterial abundance. Based on results from PCR-DGGE, three land use practices (i.e. cropland, pine forest, restoration land) showed distinct dominant bands, which were mostly affiliated with Group 1.1a. Degradation land, however, was dominated by sequences belonging to Group 1.1c. Results from this study suggest that community structure of ammonia oxidizing archaea were significantly impacted by land use practices. PMID:23774250

  15. Quantification of bacterial and archaeal symbionts in high and low microbial abundance sponges using real-time PCR.

    Science.gov (United States)

    Bayer, Kristina; Kamke, Janine; Hentschel, Ute

    2014-09-01

    In spite of considerable insights into the microbial diversity of marine sponges, quantitative information on microbial abundances and community composition remains scarce. Here, we established qPCR assays for the specific quantification of four bacterial phyla of representative sponge symbionts as well as the kingdoms Eubacteria and Archaea. We could show that the 16S rRNA gene numbers of Archaea, Chloroflexi, and the candidate phylum Poribacteria were 4-6 orders of magnitude higher in high microbial abundance (HMA) than in low microbial abundance (LMA) sponges and that actinobacterial 16S rRNA gene numbers were 1-2 orders higher in HMA over LMA sponges, while those for Cyanobacteria were stable between HMA and LMA sponges. Fluorescence in situ hybridization of Aplysina aerophoba tissue sections confirmed the numerical dominance of Chloroflexi, which was followed by Poribacteria. Archaeal and actinobacterial cells were detected in much lower numbers. By use of fluorescence-activated cell sorting as a primer- and probe-independent approach, the dominance of Chloroflexi, Proteobacteria, and Poribacteria in A. aerophoba was confirmed. Our study provides new quantitative insights into the microbiology of sponges and contributes to a better understanding of the HMA/LMA dichotomy. PMID:24942664

  16. Diversity, Abundance, and Potential Activity of Nitrifying and Nitrate-Reducing Microbial Assemblages in a Subglacial Ecosystem ▿ †

    OpenAIRE

    Boyd, Eric S.; Lange, Rachel K.; Mitchell, Andrew C.; Havig, Jeff R.; Hamilton, Trinity L.; Lafrenière, Melissa J.; Shock, Everett L.; Peters, John W.; Skidmore, Mark

    2011-01-01

    Subglacial sediments sampled from beneath Robertson Glacier (RG), Alberta, Canada, were shown to harbor diverse assemblages of potential nitrifiers, nitrate reducers, and diazotrophs, as assessed by amoA, narG, and nifH gene biomarker diversity. Although archaeal amoA genes were detected, they were less abundant and less diverse than bacterial amoA, suggesting that bacteria are the predominant nitrifiers in RG sediments. Maximum nitrification and nitrate reduction rates in microcosms incubate...

  17. Spatial and Temporal Patterns in the Microbial Diversity of a Meromictic Soda Lake in Washington State▿ †

    OpenAIRE

    Dimitriu, Pedro A; Pinkart, Holly C.; Peyton, Brent M.; Mormile, Melanie R.

    2008-01-01

    The microbial community diversity and composition of meromictic Soap Lake were studied using culture-dependent and culture-independent approaches. The water column and sediments were sampled monthly for a year. Denaturing gradient gel electrophoresis of bacterial and archaeal 16S rRNA genes showed an increase in diversity with depth for both groups. Late-summer samples harbored the highest prokaryotic diversity, and the bacteria exhibited less seasonal variability than the archaea. Most-proba...

  18. Functional interaction of yeast and human TATA-binding proteins with an archaeal RNA polymerase and promoter.

    OpenAIRE

    Wettach, J; Gohl, H P; Tschochner, H; Thomm, M

    1995-01-01

    TATA boxes are common structural features of eucaryal class II and archaeal promoters. In addition, a gene encoding a polypeptide with sequence similarity to eucaryal TATA-binding protein (TBP) has recently been detected in Archaea, but its relationship to the archaeal transcription factors A (aTFA) and B (aTFB) was unclear. Here, we demonstrate that yeast and human TBP can substitute for aTFB in a Methanococcus-derived archaeal cell-free transcription system. Template-commitment studies show...

  19. Phylogenetic biodiversity assessment based on systematic nomenclature

    Directory of Open Access Journals (Sweden)

    Ross H Crozier

    2006-01-01

    Full Text Available Biodiversity assessment demands objective measures, because ultimately conservation decisions must prioritize the use of limited resources for preserving taxa. The most general framework for the objective assessment of conservation worth are those that assess evolutionary distinctiveness, e.g. Genetic (Crozier 1992 and Phylogenetic Diversity (Faith 1992, and Evolutionary History (Nee & May 1997. These measures all attempt to assess the conservation worth of any scheme based on how much of the encompassing phylogeny of organisms is preserved. However, their general applicability is limited by the small proportion of taxa that have been reliably placed in a phylogeny. Given that phylogenizaton of many interesting taxa or important is unlikely to occur soon, we present a framework for using taxonomy as a reasonable surrogate for phylogeny. Combining this framework with exhaustive searches for combinations of sites containing maximal diversity, we provide a proof-of-concept for assessing conservation schemes for systematized but un-phylogenised taxa spread over a series of sites. This is illustrated with data from four studies, on North Queensland flightless insects (Yeates et al. 2002, ants from a Florida Transect (Lubertazzi & Tschinkel 2003, New England bog ants (Gotelli & Ellison 2002 and a simulated distribution of the known New Zealand Lepidosauria (Daugherty et al. 1994. The results support this approach, indicating that species, genus and site numbers predict evolutionary history, to a degree depending on the size of the data set.

  20. Heterogeneous diversity of spacers within CRISPR

    OpenAIRE

    He, Jiankui; Deem, Michael W.

    2010-01-01

    Clustered regularly interspaced short palindromic repeats (CRISPR) in bacterial and archaeal DNA have recently been shown to be a new type of anti-viral immune system in these organisms. We here study the diversity of spacers in CRISPR under selective pressure. We propose a population dynamics model that explains the biological observation that the leader-proximal end of CRISPR is more diversified and the leader-distal end of CRISPR is more conserved. This result is shown to be in agreement w...

  1. Phylogenetic Analysis of Vascular Endothelial Growth Factor Diversity

    OpenAIRE

    KASAP, Murat

    2005-01-01

    The secreted glycoprotein vascular endothelial growth factor (VEGF) is a potent and specific mitogen for vascular endothelial cells, capable of stimulating angiogenesis during embryonic development and tumor formation. Despite intensive research, the functions of several VEGF family members remain a mystery. Insight into their evolutionary relationships could profoundly improve our understanding of why there are so many VEGFs and why we have not been able to dissect their function to our sati...

  2. Phylogenetic Diversity and Molecular Detection of Bacteria in Gull Feces

    Science.gov (United States)

    In spite of increasing public health concerns about the potential risks associated with swimming in waters contaminated with waterfowl feces, little is known about the composition of the gut microbial community of aquatic birds. To address this, a gull 16S rDNA fecal clone librar...

  3. Phylogenetic diversity of Moroccan cork oak woodlands fungi

    Directory of Open Access Journals (Sweden)

    Abourouh M.

    2009-01-01

    Full Text Available Interspecific variation among 87 sporocarps of fungi belonging to 15 genera and 39 species were evaluated by analyzing the internal transcribed spacer (ITS of the rDNA region using restriction fragment length polymorphism (RFLP. The ITS region was first amplified by polymerase chain reaction (PCR with specific primers and then cleaved with different restriction enzymes. Amplification products, which ranged between 500 and 950 base pairs (bp, were obtained for all the isolates analyzed. The degree of polymorphism observed did not allow proper identification of most of the species. Cleavage of amplified fragments with the restriction enzymes Alu I, EcoR I and Hinf I revealed extensive polymorphism. The fifteen genera and most species presented specific restriction patterns. The only species not identifiable by a specific pattern belonged to the genera Russula (R. decipiens and R. straminea. These species might be considered as closely related species. The Pisolithus sporocarps had two ITS-RFLP types with one dominating. ITS sequencing confirms that the two RFLP types correspond to two distinct species of Pisolithus. Our data show the potential of ITS region PCR-RFLP for the molecular characterization of ectomycorrhizal fungi and their identification and monitoring in artificial inoculation programs.

  4. Taxonomic and Phylogenetic Determinants of Functional Composition of Bolivian Bat Assemblages.

    Directory of Open Access Journals (Sweden)

    Luis F Aguirre

    Full Text Available Understanding diversity patterns and the potential mechanisms driving them is a fundamental goal in ecology. Examination of different dimensions of biodiversity can provide insights into the relative importance of different processes acting upon biotas to shape communities. Unfortunately, patterns of diversity are still poorly understood in hyper-diverse tropical countries. Here, we assess spatial variation of taxonomic, functional and phylogenetic diversity of bat assemblages in one of the least studied Neotropical countries, Bolivia, and determine whether changes in biodiversity are explained by the replacement of species or functional groups, or by differences in richness (i.e., gain or loss of species or functional groups. Further, we evaluate the contribution of phylogenetic and taxonomic changes in the resulting patterns of functional diversity of bats. Using well-sampled assemblages from published studies we examine noctilionoid bats at ten study sites across five ecoregions in Bolivia. Bat assemblages differed from each other in all dimensions of biodiversity considered; however, diversity patterns for each dimension were likely structured by different mechanisms. Within ecoregions, differences were largely explained by species richness, suggesting that the gain or loss of species or functional groups (as opposed to replacement was driving dissimilarity patterns. Overall, our results suggest that whereas evolutionary processes (i.e., historical connection and dispersal routes across Bolivia create a template of diversity patterns across the country, ecological mechanisms modify these templates, decoupling the observed patterns of functional, taxonomic and phylogenetic diversity in Bolivian bats. Our results suggests that elevation represents an important source of variability among diversity patterns for each dimension of diversity considered. Further, we found that neither phylogenetic nor taxonomic diversity can fully account for

  5. Taxonomic and Phylogenetic Determinants of Functional Composition of Bolivian Bat Assemblages

    Science.gov (United States)

    Aguirre, Luis F.; Montaño-Centellas, Flavia A.; Gavilanez, M. Mercedes; Stevens, Richard D.

    2016-01-01

    Understanding diversity patterns and the potential mechanisms driving them is a fundamental goal in ecology. Examination of different dimensions of biodiversity can provide insights into the relative importance of different processes acting upon biotas to shape communities. Unfortunately, patterns of diversity are still poorly understood in hyper-diverse tropical countries. Here, we assess spatial variation of taxonomic, functional and phylogenetic diversity of bat assemblages in one of the least studied Neotropical countries, Bolivia, and determine whether changes in biodiversity are explained by the replacement of species or functional groups, or by differences in richness (i.e., gain or loss of species or functional groups). Further, we evaluate the contribution of phylogenetic and taxonomic changes in the resulting patterns of functional diversity of bats. Using well-sampled assemblages from published studies we examine noctilionoid bats at ten study sites across five ecoregions in Bolivia. Bat assemblages differed from each other in all dimensions of biodiversity considered; however, diversity patterns for each dimension were likely structured by different mechanisms. Within ecoregions, differences were largely explained by species richness, suggesting that the gain or loss of species or functional groups (as opposed to replacement) was driving dissimilarity patterns. Overall, our results suggest that whereas evolutionary processes (i.e., historical connection and dispersal routes across Bolivia) create a template of diversity patterns across the country, ecological mechanisms modify these templates, decoupling the observed patterns of functional, taxonomic and phylogenetic diversity in Bolivian bats. Our results suggests that elevation represents an important source of variability among diversity patterns for each dimension of diversity considered. Further, we found that neither phylogenetic nor taxonomic diversity can fully account for patterns of functional

  6. Growth rules based on the modularity of the Canarian Aeonium (Crassulaceae) and their phylogenetic value

    DEFF Research Database (Denmark)

    Jorgensen, T.H.; Olesen, J.M.

    2000-01-01

    models are species specific. A discriminant analysis generates a statistically significant separation of species at the level of phylogenetic sections. The results therefore demonstrate the phylogenetic value of growth rules in plants. This dynamic approach strongly contrasts with the traditional static...... view on forms in systematics and morphology. It also leaves scope for predicting the evolutionary pathways of morphological change which have caused the great diversity of growth forms in the genus Aeonium. (C) 2000 The Linnean Society of London....

  7. Reconstruction of Family-Level Phylogenetic Relationships within Demospongiae (Porifera) Using Nuclear Encoded Housekeeping Genes

    OpenAIRE

    Hill, Malcolm S.; April L Hill; Jose Lopez; Peterson, Kevin J.; Shirley Pomponi; Maria C Diaz; Thacker, Robert W; Maja Adamska; Nicole Boury-Esnault; Paco Cárdenas; Andia Chaves-Fonnegra; Elizabeth Danka; Bre-Onna De Laine; Dawn Formica; Eduardo Hajdu

    2013-01-01

    BACKGROUND: Demosponges are challenging for phylogenetic systematics because of their plastic and relatively simple morphologies and many deep divergences between major clades. To improve understanding of the phylogenetic relationships within Demospongiae, we sequenced and analyzed seven nuclear housekeeping genes involved in a variety of cellular functions from a diverse group of sponges. METHODOLOGY/PRINCIPAL FINDINGS: We generated data from each of the four sponge classes (i.e., Calcarea, ...

  8. Change in Phylogenetic Community Structure during Succession of Traditionally Managed Tropical Rainforest in Southwest China

    OpenAIRE

    Xiao-Xue Mo; Ling-Ling Shi; Yong-Jiang Zhang; Hua Zhu; Ferry Slik, J. W.

    2013-01-01

    Tropical rainforests in Southeast Asia are facing increasing and ever more intense human disturbance that often negatively affects biodiversity. The aim of this study was to determine how tree species phylogenetic diversity is affected by traditional forest management types and to understand the change in community phylogenetic structure during succession. Four types of forests with different management histories were selected for this purpose: old growth forests, understorey planted old grow...

  9. Taxonomically and functionally diverse microbial communities in deep crystalline rocks of the Fennoscandian shield

    OpenAIRE

    Nyyssönen, Mari; Hultman, Jenni; Ahonen, Lasse; Kukkonen, Ilmo; Paulin, Lars; Laine, Pia; Itävaara, Merja; Auvinen, Petri

    2013-01-01

    Microbial life in the nutrient-limited and low-permeability continental crystalline crust is abundant but remains relatively unexplored. Using high-throughput sequencing to assess the 16S rRNA gene diversity, we found diverse bacterial and archaeal communities along a 2516-m-deep drill hole in continental crystalline crust in Outokumpu, Finland. These communities varied at different sampling depths in response to prevailing lithology and hydrogeochemistry. Further analysis by shotgun metageno...

  10. Archaeal viruses: living fossils of the ancient virosphere?

    Science.gov (United States)

    Prangishvili, David

    2015-04-01

    Studies on viruses parasitizing archaea reveal their specific nature and complete the tripartite division of the biosphere, indicating that each of the three domains of life-Archaea, Bacteria, and Eukarya-has its own set of associated DNA viruses. I argue that the remarkable morphotypical diversity of archaea-specific viruses could have originated from diverse viral archetypes that predated the divergence of the three domains of cellular life. It is possible that the descendants of many of these viral archetypes are able to parasitize extant archaea owing to their ability to evade archaea-specific defenses against virus infection, specifically the defenses linked to the evolution of cell envelope structure. PMID:25716458

  11. Phylogenetic Position of Barbus lacerta Heckel, 1843

    Directory of Open Access Journals (Sweden)

    Mustafa Korkmaz

    2015-11-01

    As a result, five clades come out from phylogenetic reconstruction and in phylogenetic tree Barbus lacerta determined to be sister group of Barbus macedonicus, Barbus oligolepis and Barbus plebejus complex.

  12. PhyloSift: phylogenetic analysis of genomes and metagenomes

    Directory of Open Access Journals (Sweden)

    Aaron E. Darling

    2014-01-01

    Full Text Available Like all organisms on the planet, environmental microbes are subject to the forces of molecular evolution. Metagenomic sequencing provides a means to access the DNA sequence of uncultured microbes. By combining DNA sequencing of microbial communities with evolutionary modeling and phylogenetic analysis we might obtain new insights into microbiology and also provide a basis for practical tools such as forensic pathogen detection. In this work we present an approach to leverage phylogenetic analysis of metagenomic sequence data to conduct several types of analysis. First, we present a method to conduct phylogeny-driven Bayesian hypothesis tests for the presence of an organism in a sample. Second, we present a means to compare community structure across a collection of many samples and develop direct associations between the abundance of certain organisms and sample metadata. Third, we apply new tools to analyze the phylogenetic diversity of microbial communities and again demonstrate how this can be associated to sample metadata. These analyses are implemented in an open source software pipeline called PhyloSift. As a pipeline, PhyloSift incorporates several other programs including LAST, HMMER, and pplacer to automate phylogenetic analysis of protein coding and RNA sequences in metagenomic datasets generated by modern sequencing platforms (e.g., Illumina, 454.

  13. Phylogenetic signal in diatom ecology: perspectives for aquatic ecosystems biomonitoring.

    Science.gov (United States)

    Keck, François; Rimet, Frédéric; Franc, Alain; Bouchez, Agnés

    2016-04-01

    Diatoms include a great diversity of taxa and are recognized as powerful bioindicators in rivers. However using diatoms for monitoring programs is costly and time consuming because most of the methodologies necessitate species-level identification. This raises the question of the optimal trade-off between taxonomic resolution and bioassessment quality. Phylogenetic tools may form the bases of new, more efficient approaches for biomonitoring if relationships between ecology and phylogeny can be demonstrated. We estimated the ecological optima of 127 diatom species for 19 environmental parameters using count data from 2119 diatom communities sampled during eight years in eastern France. Using uni- and multivariate analyses, we explored the relationships between freshwater diatom phylogeny and ecology (i.e., the phylogenetic signal). We found a significant phylogenetic signal for many of the ecological optima that were tested, but the strength of the signal varied significantly from one trait to another. Multivariate analysis also showed that the multidimensional ecological niche of diatoms can be strongly related to phylogeny. The presence of clades containing species that exhibit homogeneous ecology suggests that phylogenetic information can be useful for aquatic biomonitoring. This study highlights the presence of significant patterns of ecological optima for freshwater diatoms in relation to their phylogeny. These results suggest the presence of a signal above the species level, which is encouraging for the development of simplified methods for biomonitoring survey. PMID:27411256

  14. Phylogenetic Distribution of Fungal Sterols

    OpenAIRE

    Weete, John D.; Abril, Maritza; Blackwell, Meredith

    2010-01-01

    Background Ergosterol has been considered the “fungal sterol” for almost 125 years; however, additional sterol data superimposed on a recent molecular phylogeny of kingdom Fungi reveals a different and more complex situation. Methodology/Principal Findings The interpretation of sterol distribution data in a modern phylogenetic context indicates that there is a clear trend from cholesterol and other Δ5 sterols in the earliest diverging fungal species to ergosterol in later diverging fungi. The...

  15. Genetic divergence and molecular phylogenetics of Puntius spp. based on the mitochondrial cytochrome b gene.

    Science.gov (United States)

    Pallavi; Goswami, M; Nautiyal, P; Malakar, A K; Nagpure, N S

    2012-12-01

    Puntius is an important genus of freshwater food and ornamental fish belonging to the family Cyprinidae. A total of 60 samples from twelve species of the genus Puntius were collected from eight sampling sites of eight Indian Rivers. Twelve species of Puntius (P. chola, P. sophore, P. filamentosus, P. fasciatus, P. vittatus, P. chelynoides, P. gonionotus, P. denisonii, P. ticto, P. gelius, P. conchonius and P. sarana) were investigated using 60 partial sequences of the mitochondrial cytochrome b (Cyt b, 1096 bp) gene to estimate genetic divergence and to establish the phylogenetic relationship. The average intraspecies diversity was estimated as 0.002, whereas the average interspecies diversity was estimated as 0.177. The sequence analysis of the Cyt b gene revealed four distinct groups, which are genetically distinct species and exhibited identical phylogenetic relationship. The present study validated the utility of the Cyt b gene in genetic diversity and phylogenetic studies. PMID:22943631

  16. The Vertical Distribution of Sediment Archaeal Community in the “Black Bloom” Disturbing Zhushan Bay of Lake Taihu

    Science.gov (United States)

    Fan, Xianfang; Xing, Peng

    2016-01-01

    Using the Illumina sequencing technology, we investigated the vertical distribution of archaeal community in the sediment of Zhushan Bay of Lake Taihu, where the black bloom frequently occurred in summer. Overall, the Miscellaneous Crenarchaeotal Group (MCG), Deep Sea Hydrothermal Vent Group 6 (DHVEG-6), and Methanobacterium dominated the archaeal community. However, we observed significant difference in composition of archaeal community among different depths of the sediment. DHVEG-6 dominated in the surface layer (0–3 cm) sediment. Methanobacterium was the dominating archaeal taxa in the L2 (3–6 cm) and L3 (6–10) sediment. MCG was most abundant in the L4 (10–15 cm) and L5 (15–20 cm) sediment. Besides, DHVEG-6 was significantly affected by the concentration of total phosphorus (TP). And loss on ignition (LOI) was an important environmental factor for Methanobacterium. As the typical archaeal taxa in the surface layer sediment, DHVEG-6 and Methanobacterium might be more adapted to abundant substrate supply from cyanobacterial blooms and take active part in the biomass transformation. We propose that DHVEG-6 and Methanobacterium could be the key archaeal taxa correlated with the “black bloom” formation in Zhushan Bay. PMID:26884723

  17. An archaeal tRNA-synthetase complex that enhances aminoacylation under extreme conditions

    DEFF Research Database (Denmark)

    Godinic-Mikulcic, Vlatka; Jaric, Jelena; Hausmann, Corinne D;

    2011-01-01

    Aminoacyl-tRNA synthetases (aaRSs) play an integral role in protein synthesis, functioning to attach the correct amino acid with its cognate tRNA molecule. AaRSs are known to associate into higher-order multi-aminoacyl-tRNA synthetase complexes (MSC) involved in archaeal and eukaryotic translation...... the catalytic efficiency of serine attachment to tRNA, but had no effect on the activity of MtArgRS. Further, the most pronounced improvements in the aminoacylation activity of MtSerRS induced by MtArgRS were observed under conditions of elevated temperature and osmolarity. These data indicate that......, although the precise biological role remains largely unknown. To gain further insights into archaeal MSCs, possible protein-protein interactions with the atypical Methanothermobacter thermautotrophicus seryl-tRNA synthetase (MtSerRS) were investigated. Yeast two-hybrid analysis revealed arginyl-tRNA...

  18. Expression, purification and crystallization of an archaeal-type phosphoenolpyruvate carboxylase

    International Nuclear Information System (INIS)

    The expression, purification, crystallization and preliminary diffraction analysis of an archaeal-type phosphoenolpyruvate carboxylase are described. Complete highly redundant X-ray data have been measured from a crystal diffracting to 3.13 Å resolution. An archaeal-type phosphoenolpyruvate carboxylase (PepcA) from Clostridium perfringens has been expressed in Escherichia coli in a soluble form with an amino-terminal His tag. The recombinant protein is enzymatically active and two crystal forms have been obtained. Complete diffraction data extending to 3.13 Å resolution have been measured from a crystal soaked in KAu(CN)2, using radiation at a wavelength just above the Au LIII edge. The asymmetric unit contains two tetramers of PepcA

  19. Analysis of Genetic Diversity of the mtDNA D-Loop Regions and Phylogenetic Evolution of Chinese Local Cattle%中国部分地方牛种mtDNA D-loop区全序列的遗传多样性与系统进化分析

    Institute of Scientific and Technical Information of China (English)

    马云; 于波; 徐永杰; 吴海港; 梁小娟; 付蕾; 李芬

    2012-01-01

    Using PCR technology, sequencing technologies and bioinformatics analysis technology to amplify and analyze the mtDNA D-loop region complete sequence of four local cattle varieties,a hybrid cattle variety,five local buffalo species and two local yak breeds. The results showed that Chinese domestic buffalo,yak and cattle breeds had rich mitochondrial genetic diversity. Based on the mtDNA D-loop sequences, the phylogeny of the representative species of buffalo,cattle,yak,wild yak,Bos Taurus,Bos indicus and rivers of India-based buffalo were analyzed. The phylogenetic relationships showed that cattle and yaks clustered into one,buffalo alone clustered into one. This means cattle have a close relationship with yaks with a distant relationship with buffalo. China buffalo belong to the swamp type water buffalo, but a small number of rivers type water buffalo gradually mixed into the China buffalo groups. Chinese cattle for the Bos taunts and the Bos indicus mixture of maternal origin; phylogenetic tree showed that the plateau yak has a close relationship with the wild yak,the lake yak has a close relationship with the domestic yak.%利用PCR测序及生物信息学分析技术,对我国5个地方黄牛品种、5个地方水牛品种及2个地方牦牛品种的mtDNA D-loop区全序列进行PCR扩增以及核苷酸多样度、单倍型多样度分析,发现中国地方黄牛、水牛与牦牛具有丰富的遗传多样性.对试验牛mtDNA D-loop区全序列与牛亚科代表性物种黄牛、水牛、家牦牛、野牦牛、欧洲普通牛、印度瘤牛以及摩拉水牛相应序列进行系统发育分析.结果显示:黄牛与牦牛的亲缘关系较近,它们与水牛的亲缘关系较远;中国水牛属于沼泽型水牛,也有少量江河型水牛渐渗入中国水牛群体;中国黄牛为普通牛和瘤牛的混合母系起源;进化树显示高原牦牛与野牦牛的素缘关系较近,环湖牦牛与家牦牛的亲缘关系较近.

  20. Transforming phylogenetic networks: Moving beyond tree space.

    Science.gov (United States)

    Huber, Katharina T; Moulton, Vincent; Wu, Taoyang

    2016-09-01

    Phylogenetic networks are a generalization of phylogenetic trees that are used to represent reticulate evolution. Unrooted phylogenetic networks form a special class of such networks, which naturally generalize unrooted phylogenetic trees. In this paper we define two operations on unrooted phylogenetic networks, one of which is a generalization of the well-known nearest-neighbor interchange (NNI) operation on phylogenetic trees. We show that any unrooted phylogenetic network can be transformed into any other such network using only these operations. This generalizes the well-known fact that any phylogenetic tree can be transformed into any other such tree using only NNI operations. It also allows us to define a generalization of tree space and to define some new metrics on unrooted phylogenetic networks. To prove our main results, we employ some fascinating new connections between phylogenetic networks and cubic graphs that we have recently discovered. Our results should be useful in developing new strategies to search for optimal phylogenetic networks, a topic that has recently generated some interest in the literature, as well as for providing new ways to compare networks. PMID:27224010

  1. Eukaryotic and archaeal TBP and TFB/TF(II)B follow different promoter DNA bending pathways

    OpenAIRE

    Gietl, Andreas; Holzmeister, Phil; Blombach, Fabian; Schulz, Sarah; von Voithenberg, Lena Voith; Lamb, Don C; Werner, Finn; Tinnefeld, Philip; Grohmann, Dina

    2014-01-01

    During transcription initiation, the promoter DNA is recognized and bent by the basal transcription factor TATA-binding protein (TBP). Subsequent association of transcription factor B (TFB) with the TBP–DNA complex is followed by the recruitment of the ribonucleic acid polymerase resulting in the formation of the pre-initiation complex. TBP and TFB/TF(II)B are highly conserved in structure and function among the eukaryotic-archaeal domain but intriguingly have to operate under vastly differen...

  2. Events during Initiation of Archaeal Transcription: Open Complex Formation and DNA-Protein Interactions

    OpenAIRE

    Hausner, Winfried; Thomm, Michael

    2001-01-01

    Transcription in Archaea is initiated by association of a TATA box binding protein (TBP) with a TATA box. This interaction is stabilized by the binding of the transcription factor IIB (TFIIB) orthologue TFB. We show here that the RNA polymerase of the archaeon Methanococcus, in contrast to polymerase II, does not require hydrolysis of the β-γ bond of ATP for initiation of transcription and open complex formation on linearized DNA. Permanganate probing revealed that the archaeal open complex s...

  3. Activation of archaeal transcription mediated by recruitment of transcription factor B.

    Science.gov (United States)

    Ochs, Simon M; Thumann, Sybille; Richau, Renate; Weirauch, Matt T; Lowe, Todd M; Thomm, Michael; Hausner, Winfried

    2012-05-25

    Archaeal promoters consist of a TATA box and a purine-rich adjacent upstream sequence (transcription factor B (TFB)-responsive element (BRE)), which are bound by the transcription factors TATA box-binding protein (TBP) and TFB. Currently, only a few activators of archaeal transcription have been experimentally characterized. The best studied activator, Ptr2, mediates activation by recruitment of TBP. Here, we present a detailed biochemical analysis of an archaeal transcriptional activator, PF1088, which was identified in Pyrococcus furiosus by a bioinformatic approach. Operon predictions suggested that an upstream gene, pf1089, is polycistronically transcribed with pf1088. We demonstrate that PF1088 stimulates in vitro transcription by up to 7-fold when the pf1089 promoter is used as a template. By DNase I and hydroxyl radical footprinting experiments, we show that the binding site of PF1088 is located directly upstream of the BRE of pf1089. Mutational analysis indicated that activation requires the presence of the binding site for PF1088. Furthermore, we show that activation of transcription by PF1088 is dependent upon the presence of an imperfect BRE and is abolished when the pf1089 BRE is replaced with a BRE from a strong archaeal promoter. Gel shift experiments showed that TFB recruitment to the pf1089 operon is stimulated by PF1088, and TFB seems to stabilize PF1088 operator binding even in the absence of TBP. Taken together, these results represent the first biochemical evidence for a transcriptional activator working as a TFB recruitment factor in Archaea, for which the designation TFB-RF1 is suggested. PMID:22496454

  4. Archaeal Transcription: Function of an Alternative Transcription Factor B from Pyrococcus furiosus▿

    OpenAIRE

    Micorescu, Michael; Grünberg, Sebastian; Franke, Andreas; Cramer, Patrick; Thomm, Michael; Bartlett, Michael

    2007-01-01

    The genome of the hyperthermophile archaeon Pyrococcus furiosus encodes two transcription factor B (TFB) paralogs, one of which (TFB1) was previously characterized in transcription initiation. The second TFB (TFB2) is unusual in that it lacks recognizable homology to the archaeal TFB/eukaryotic TFIIB B-finger motif. TFB2 functions poorly in promoter-dependent transcription initiation, but photochemical cross-linking experiments indicated that the orientation and occupancy of transcription com...

  5. The σ enigma: Bacterial σ factors, archaeal TFB and eukaryotic TFIIB are homologs

    OpenAIRE

    Burton, Samuel P; Burton, Zachary F.

    2014-01-01

    Structural comparisons of initiating RNA polymerase complexes and structure-based amino acid sequence alignments of general transcription initiation factors (eukaryotic TFIIB, archaeal TFB and bacterial σ factors) show that these proteins are homologs. TFIIB and TFB each have two-five-helix cyclin-like repeats (CLRs) that include a C-terminal helix-turn-helix (HTH) motif (CLR/HTH domains). Four homologous HTH motifs are present in bacterial σ factors that are relics of CLR/HTH domains. Sequen...

  6. Factors Controlling the Distribution of Archaeal Tetraethers in Terrestrial Hot Springs▿

    OpenAIRE

    Pearson, Ann; Pi, Yundan; Zhao, Weidong; Li, Wenjun; Li, Yiliang; Inskeep, William; Perevalova, Anna; Romanek, Christopher; Li, Shuguang; Zhang, Chuanlun L.

    2008-01-01

    Glycerol dialkyl glycerol tetraethers (GDGTs) found in hot springs reflect the abundance and community structure of Archaea in these extreme environments. The relationships between GDGTs, archaeal communities, and physical or geochemical variables are underexamined to date and when reported often result in conflicting interpretations. Here, we examined profiles of GDGTs from pure cultures of Crenarchaeota and from terrestrial geothermal springs representing a wide distribution of locations, i...

  7. A site-specific endonuclease encoded by a typical archaeal intron

    DEFF Research Database (Denmark)

    Dalgaard, Jacob; Garrett, Roger Antony; Belfort, Malene

    1993-01-01

    The protein encoded by the archaeal intron in the 23S rRNA gene of the hyperthermophile Desulfurococcus mobilis is a double-strand DNase that, like group I intron homing endonucleases, is capable of cleaving an intronless allele of the gene. This enzyme, I-Dmo I, is unusual among the intron endon...... of endonucleases and intron core elements and are consistent with the invasive potential of endonuclease genes....

  8. Fossilization and degradation of archaeal intact polar tetraether lipids in deeply buried marine sediments (Peru Margin)

    OpenAIRE

    Lengger, S. K.; Hopmans, E.C.; Sinninghe Damsté, J.S.; Schouten, S.

    2014-01-01

    Glycerol dibiphytanyl glycerol tetraether (GDGT) lipids are part of the cellular membranes of Thaumarchaeota, an archaeal phylum composed of aerobic ammonia oxidizers, and are used in the paleotemperature proxy TEX86. GDGTs in live cells possess polar head groups and are called intact polar lipids (IPL-GDGTs). Their transformation to core lipids (CL) by cleavage of the head group was assumed to proceed rapidly after cell death, but it has been suggested that some of these IPL-GDGTs can, just ...

  9. Significance of archaeal nitrification in hypoxic waters of the Baltic Sea

    OpenAIRE

    Berg, Carlo; Vandieken, Verona; Thamdrup, Bo; Jürgens, Klaus

    2014-01-01

    Ammonia-oxidizing archaea (AOA) of the phylum Thaumarchaeota are widespread, and their abundance in many terrestrial and aquatic ecosystems suggests a prominent role in nitrification. AOA also occur in high numbers in oxygen-deficient marine environments, such as the pelagic redox gradients of the central Baltic Sea; however, data on archaeal nitrification rates are scarce and little is known about the factors, for example sulfide, that regulate nitrification in this system. In the present wo...

  10. Global Occurrence of Archaeal amoA Genes in Terrestrial Hot Springs▿

    OpenAIRE

    Zhang, Chuanlun L.; Ye, Qi; Huang, Zhiyong; Li, Wenjun; Chen, Jinquan; Song, Zhaoqi; Zhao, Weidong; Bagwell, Christopher; Inskeep, William P.; Ross, Christian; Gao, Lei; Wiegel, Juergen; Romanek, Christopher S.; Shock, Everett L.; Hedlund, Brian P.

    2008-01-01

    Despite the ubiquity of ammonium in geothermal environments and the thermodynamic favorability of aerobic ammonia oxidation, thermophilic ammonia-oxidizing microorganisms belonging to the crenarchaeota kingdom have only recently been described. In this study, we analyzed microbial mats and surface sediments from 21 hot spring samples (pH 3.4 to 9.0; temperature, 41 to 86°C) from the United States, China, and Russia and obtained 846 putative archaeal ammonia monooxygenase large-subunit (amoA) ...

  11. Temporal changes in soil bacterial and archaeal communities with different fertilizers in tea orchards* #

    OpenAIRE

    Wang, Hua; Yang, Shao-hui; Yang, Jing-ping; Lv, Ya-min; Zhao, Xing; Pang, Ji-liang

    2014-01-01

    It is important to understand the effects of temporal changes in microbial communities in the acidic soils of tea orchards with different fertilizers. A field experiment involving organic fertilizer (OF), chemical fertilizer (CF), and unfertilized control (CK) treatments was arranged to analyze the temporal changes in the bacterial and archaeal communities at bimonthly intervals based on the 16S ribosomal RNA (rRNA) gene using terminal restriction fragment length polymorphism (T-RFLP) profili...

  12. Functional and phylogenetic ecology in R

    CERN Document Server

    Swenson, Nathan G

    2014-01-01

    Functional and Phylogenetic Ecology in R is designed to teach readers to use R for phylogenetic and functional trait analyses. Over the past decade, a dizzying array of tools and methods were generated to incorporate phylogenetic and functional information into traditional ecological analyses. Increasingly these tools are implemented in R, thus greatly expanding their impact. Researchers getting started in R can use this volume as a step-by-step entryway into phylogenetic and functional analyses for ecology in R. More advanced users will be able to use this volume as a quick reference to understand particular analyses. The volume begins with an introduction to the R environment and handling relevant data in R. Chapters then cover phylogenetic and functional metrics of biodiversity; null modeling and randomizations for phylogenetic and functional trait analyses; integrating phylogenetic and functional trait information; and interfacing the R environment with a popular C-based program. This book presents a uni...

  13. An explosive innovation: Phylogenetic relationships of Solanum section Gonatotrichum (Solanaceae

    Directory of Open Access Journals (Sweden)

    Stephen Stern

    2012-01-01

    Full Text Available Solanum is one of the largest plant genera and exhibits a wide range of morphological diversity. Solanum section Gonatotrichum, the focus of this study, is unique within the genus because of its fruits that swell with turgor pressure and explosively dehisce to disperse the seeds. We infer phylogenetic relationships within section Gonatotrichum using DNA sequence data from two nuclear regions (ITS and the granule-bound starch synthase gene [GBSSI or waxy] and the chloroplast region trnT-F. The resulting phylogenetic trees support the monophyly of the section with the inclusion of S. lignescens, a species not previously thought to belong to the group due to the presence of stellate hairs. This inclusion of this species in section Gonatotrichum suggests that the simple, often geniculate hairs of species in the group may represent reduced stellate hairs. The presence of heterantherous flowers appears to be derived in the section, but this character is largely lost in S. parcistrigosum.

  14. Chemical multi-contamination drives benthic prokaryotic diversity in the anthropized Toulon Bay.

    Science.gov (United States)

    Misson, Benjamin; Garnier, Cédric; Lauga, Béatrice; Dang, Duc Huy; Ghiglione, Jean-François; Mullot, Jean-Ulrich; Duran, Robert; Pringault, Olivier

    2016-06-15

    Investigating the impact of human activities on marine coastal ecosystems remains difficult because of the co-occurrence of numerous natural and human-induced gradients. Our aims were (i) to evaluate the links between the chemical environment as a whole and microbial diversity in the benthic compartment, and (ii) to compare the contributions of anthropogenic and natural chemical gradients to microbial diversity shifts. We studied surface sediments from 54 sampling sites in the semi-enclosed Toulon Bay (NW Mediterranean) exposed to high anthropogenic pressure. Previously published chemical data were completed by new measurements, resulting in an in depth geochemical characterization by 29 representative environmental variables. Bacterial and archaeal diversity was assessed by terminal restriction fragment length polymorphism profiling on a selection of samples distributed along chemical gradients. Multivariate statistical analyses explained from 45% to 80% of the spatial variation in microbial diversity, considering only the chemical variables. A selection of trace metals of anthropogenic origin appeared to be strong structural factors for both bacterial and archaeal communities. Bacterial terminal restriction fragment (T-RF) richness correlated strongly with both anthropogenic and natural chemical gradients, whereas archaeal T-RF richness demonstrated fewer links with chemical variables. No significant decrease in diversity was evidenced in relation to chemical contamination, suggesting a high adaptive potential of benthic microbial communities in Toulon Bay. PMID:27032072

  15. Phylogenetics of neotropical Platymiscium (Leguminosae

    DEFF Research Database (Denmark)

    Saslis-Lagoudakis, C. Haris; Chase, Mark W; Robinson, Daniel N;

    2008-01-01

    Platymiscium is a neotropical legume genus of forest trees in the Pterocarpus clade of the pantropical "dalbergioid" clade. It comprises 19 species (29 taxa), distributed from Mexico to southern Brazil. This study presents a molecular phylogenetic analysis of Platymiscium and allies inferred from...... nuclear ribosomal (nrITS) and plastid (trnL, trnL-F and matK) DNA sequence data using parsimony and Bayesian methods. Divergence times are estimated using a Bayesian method assuming a relaxed molecular clock (multidivtime). Within the Pterocarpus clade, new sister relationships are recovered: Pterocarpus...

  16. Phylogenetic placement of the Spirosomaceae

    Science.gov (United States)

    Woese, C. R.; Maloy, S.; Mandelco, L.; Raj, H. D.

    1990-01-01

    Comparative analysis of 16S rRNA sequences shows that the family Spirosomaceae belongs within the eubacterial phylum defined by the flavobacteria and bacteriodes. Its constituent genera, Spirosoma, Flectobacillus, and Runella form a monophyletic grouping therein. The phylogenetic assignment is based not only upon evolutionary distance analysis, but also upon sequence signatures and higher order structural synapomorphies in 16S rRNA. Another genus peripherally associated with the Spirosomaceae, Ancylobacter ("Microcyclus"), does not cluster with the flavobacteria and their relatives, but rather belongs to the alpha subdivision of the purple bacteria.

  17. Virus Movement Maintains Local Virus Population Diversity

    Energy Technology Data Exchange (ETDEWEB)

    J. Snyder; B. Wiedenheft; M. Lavin; F. Roberto; J. Spuhler; A. Ortmann; T. Douglas; M. Young

    2007-11-01

    Viruses are the largest reservoir of genetic material on the planet, yet little is known about the population dynamics of any virus within its natural environment. Over a 2-year period, we monitored the diversity of two archaeal viruses found in hot springs within Yellowstone National Park (YNP). Both temporal phylogeny and neutral biodiversity models reveal that virus diversity in these local environments is not being maintained by mutation but rather by high rates of immigration from a globally distributed metacommunity. These results indicate that geographically isolated hot springs are readily able to exchange viruses. The importance of virus movement is supported by the detection of virus particles in air samples collected over YNP hot springs and by their detection in metacommunity sequencing projects conducted in the Sargasso Sea. Rapid rates of virus movement are not expected to be unique to these archaeal viruses but rather a common feature among virus metacommunities. The finding that virus immigration rather than mutation can dominate community structure has significant implications for understanding virus circulation and the role that viruses play in ecology and evolution by providing a reservoir of mobile genetic material.

  18. Diversity of Thermophilic Microorganisms within Hawaiian Fumaroles

    Science.gov (United States)

    Ackerman, C. A.; Anderson, S.; Anderson, C.

    2007-12-01

    Fumaroles provide heat and moisture characteristic of an environment suitable for thermophilic microorganisms. On the Island of Hawaii, fumaroles are scattered across the southeastern portion of the island as a result of the volcanic activity from Kilauea Crater and Pu'u' O'o vent. We used metagenomics to detect 16S rDNA from archaeal and bacterial thermophilic microorganisms indicating their presence in Hawaiian fumaroles. The fumaroles sampled exist along elevation and precipitation gradients; varying from sea level to 4,012ft and annual rainfall from less than 20in to greater than 80in. To determine the effects of environmental gradients (including temperature, pH, elevation, and precipitation) on microbial diversity within and among fumaroles, we obtained 22 samples from 7 fumaroles over a three-day period in February of 2007. Temperature variations within individual fumaroles vary from 2.3oC to 35oC and the pH variances that range from 0.4 to 2.0. Temperatures of the different fumaroles range from 29.9oC to greater than 105oC, with pH values that vary from 2.55 to 6.93. Further data on the microbial diversity within fumaroles and among fumaroles will be determined once the sequencing of the microbial 16S rDNA regions is completed. We are currently assembling and sequencing clone libraries of bacterial and archaeal 16S rDNA fragments from fumaroles.

  19. Characterization of an archaeal two-component system that regulates methanogenesis in Methanosaeta harundinacea.

    Directory of Open Access Journals (Sweden)

    Jie Li

    Full Text Available Two-component signal transduction systems (TCSs are a major mechanism used by bacteria in response to environmental changes. Although many sequenced archaeal genomes encode TCSs, they remain poorly understood. Previously, we reported that a methanogenic archaeon, Methanosaeta harundinacea, encodes FilI, which synthesizes carboxyl-acyl homoserine lactones, to regulate transitions of cellular morphology and carbon metabolic fluxes. Here, we report that filI, the cotranscribed filR2, and the adjacent filR1 constitute an archaeal TCS. FilI possesses a cytoplasmic kinase domain (histidine kinase A and histidine kinase-like ATPase and its cognate response regulator. FilR1 carries a receiver (REC domain coupled with an ArsR-related domain with potential DNA-binding ability, while FilR2 carries only a REC domain. In a phosphorelay assay, FilI was autophosphorylated and specifically transferred the phosphoryl group to FilR1 and FilR2, confirming that the three formed a cognate TCS. Through chromatin immunoprecipitation-quantitative polymerase chain reaction (ChIP-qPCR using an anti-FilR1 antibody, FilR1 was shown to form in vivo associations with its own promoter and the promoter of the filI-filR2 operon, demonstrating a regulatory pattern common among TCSs. ChIP-qPCR also detected FilR1 associations with key genes involved in acetoclastic methanogenesis, acs4 and acs1. Electrophoretic mobility shift assays confirmed the in vitro tight binding of FilR1 to its own promoter and those of filI-filR2, acs4, and mtrABC. This also proves the DNA-binding ability of the ArsR-related domain, which is found primarily in Archaea. The archaeal promoters of acs4, filI, acs1, and mtrABC also initiated FilR1-modulated expression in an Escherichia coli lux reporter system, suggesting that FilR1 can up-regulate both archaeal and bacterial transcription. In conclusion, this work identifies an archaeal FilI/FilRs TCS that regulates the methanogenesis of M. harundinacea.

  20. Conversion of upland to paddy field specifically alters the community structure of archaeal ammonia oxidizers in an acid soil

    Directory of Open Access Journals (Sweden)

    M. S. Alam

    2013-08-01

    Full Text Available The function of ammonia-oxidizing archaea (AOA and bacteria (AOB depends on the major energy-generating compounds (i.e., ammonia and oxygen. The diversification of AOA and AOB communities along ecological gradients of substrate availability in a complex environment have been much debated but rarely tested. In this study, two ecosystems of maize and rice crops under different fertilization regimes were selected to investigate the community diversification of soil AOA and AOB upon conversion of an upland field to a paddy field and long-term field fertilization in an acid soil. Real-time quantitative polymerase chain reaction of ammonia monooxygenase (amoA genes demonstrated that the abundance of AOA was significantly stimulated after conversion of upland to paddy soils for more than 100 yr, whereas a slight decline in AOB numbers was observed. Denaturing gradient gel electrophoresis fingerprints of amoA genes further revealed remarkable changes in the community compositions of AOA after conversion of aerobic upland to flooded paddy field. Sequencing analysis revealed that upland soil was dominated by AOA within the soil group 1.1b lineage, whereas the marine group 1.1a-associated lineage predominated in AOA communities in paddy soils. Irrespective of whether the soil was upland or paddy soil, long-term field fertilization led to increased abundance of amoA genes in AOA and AOB compared with control treatments (no fertilization, whereas archaeal amoA gene abundances outnumbered their bacterial counterparts in all samples. Phylogenetic analyses of amoA genes showed that Nitrosospira cluster-3-like AOB dominated bacterial ammonia oxidizers in both paddy and upland soils, regardless of fertilization treatment. The results of this study suggest that the marine group 1.1a-associated AOA will be better adapted to the flooded paddy field than AOA ecotypes of the soil group 1.1b lineage, and indicate that long-term flooding is the dominant selective force

  1. Conversion of upland to paddy field specifically alters the community structure of archaeal ammonia oxidizers in an acid soil

    Science.gov (United States)

    Alam, M. S.; Ren, G. D.; Lu, L.; Zheng, Y.; Peng, X. H.; Jia, Z. J.

    2013-08-01

    The function of ammonia-oxidizing archaea (AOA) and bacteria (AOB) depends on the major energy-generating compounds (i.e., ammonia and oxygen). The diversification of AOA and AOB communities along ecological gradients of substrate availability in a complex environment have been much debated but rarely tested. In this study, two ecosystems of maize and rice crops under different fertilization regimes were selected to investigate the community diversification of soil AOA and AOB upon conversion of an upland field to a paddy field and long-term field fertilization in an acid soil. Real-time quantitative polymerase chain reaction of ammonia monooxygenase (amoA) genes demonstrated that the abundance of AOA was significantly stimulated after conversion of upland to paddy soils for more than 100 yr, whereas a slight decline in AOB numbers was observed. Denaturing gradient gel electrophoresis fingerprints of amoA genes further revealed remarkable changes in the community compositions of AOA after conversion of aerobic upland to flooded paddy field. Sequencing analysis revealed that upland soil was dominated by AOA within the soil group 1.1b lineage, whereas the marine group 1.1a-associated lineage predominated in AOA communities in paddy soils. Irrespective of whether the soil was upland or paddy soil, long-term field fertilization led to increased abundance of amoA genes in AOA and AOB compared with control treatments (no fertilization), whereas archaeal amoA gene abundances outnumbered their bacterial counterparts in all samples. Phylogenetic analyses of amoA genes showed that Nitrosospira cluster-3-like AOB dominated bacterial ammonia oxidizers in both paddy and upland soils, regardless of fertilization treatment. The results of this study suggest that the marine group 1.1a-associated AOA will be better adapted to the flooded paddy field than AOA ecotypes of the soil group 1.1b lineage, and indicate that long-term flooding is the dominant selective force driving the

  2. Many-core algorithms for statistical phylogenetics

    OpenAIRE

    Suchard, Marc A.; Rambaut, Andrew

    2009-01-01

    Motivation: Statistical phylogenetics is computationally intensive, resulting in considerable attention meted on techniques for parallelization. Codon-based models allow for independent rates of synonymous and replacement substitutions and have the potential to more adequately model the process of protein-coding sequence evolution with a resulting increase in phylogenetic accuracy. Unfortunately, due to the high number of codon states, computational burden has largely thwarted phylogenetic re...

  3. Spatial and seasonal variation in microbial diversity in marine subtidal sediments in relation to sediment geochemistry and heavy metal pollution

    OpenAIRE

    Pede, A.; Gillan, D.; Gao, Y.; Billon, G.; Lesven, L.; Leermakers, M; Baeyens, W.; Vyverman, W.; Sabbe, K

    2009-01-01

    Very little information is available on the diversity and structure of microbial communities in marine subtidal sediments, especially for micro-eukaryotes. In the framework of the Belgian MICROMET project, we investigated spatial and seasonal (February vs July) variation patterns in the molecular diversity of archaeal, bacterial and eukaryotic communities in 9 subtidal stations in the Belgian Continental Plate (BCP) in relation to sediment granulometry, geochemistry and metal contamination. M...

  4. Phylogenetic and Microsatellite Markers for Tulasnella (Tulasnellaceae Mycorrhizal Fungi Associated with Australian Orchids

    Directory of Open Access Journals (Sweden)

    Monica P. Ruibal

    2013-03-01

    Full Text Available Premise of the study: Phylogenetic and microsatellite markers were developed for Tulasnella mycorrhizal fungi to investigate fungal species identity and diversity. These markers will be useful in future studies investigating the phylogenetic relationship of the fungal symbionts, specificity of orchid–mycorrhizal associations, and the role of mycorrhizae in orchid speciation within several orchid genera. Methods and Results: We generated partial genome sequences of two Tulasnella symbionts originating from Chiloglottis and Drakaea orchid species with 454 genome sequencing. Cross-genus transferability across mycorrhizal symbionts associated with multiple genera of Australian orchids (Arthrochilus, Chiloglottis, Drakaea, and Paracaleana was found for seven phylogenetic loci. Five loci showed cross-transferability to Tulasnella from other orchid genera, and two to Sebacina. Furthermore, 11 polymorphic microsatellite loci were developed for Tulasnella from Chiloglottis. Conclusions: Highly informative markers were obtained, allowing investigation of mycorrhizal diversity of Tulasnellaceae associated with a wide variety of terrestrial orchids in Australia and potentially worldwide.

  5. Bacterial and archaeal communities in the deep-sea sediments of inactive hydrothermal vents in the Southwest India Ridge.

    Science.gov (United States)

    Zhang, Likui; Kang, Manyu; Xu, Jiajun; Xu, Jian; Shuai, Yinjie; Zhou, Xiaojian; Yang, Zhihui; Ma, Kesen

    2016-01-01

    Active deep-sea hydrothermal vents harbor abundant thermophilic and hyperthermophilic microorganisms. However, microbial communities in inactive hydrothermal vents have not been well documented. Here, we investigated bacterial and archaeal communities in the two deep-sea sediments (named as TVG4 and TVG11) collected from inactive hydrothermal vents in the Southwest India Ridge using the high-throughput sequencing technology of Illumina MiSeq2500 platform. Based on the V4 region of 16S rRNA gene, sequence analysis showed that bacterial communities in the two samples were dominated by Proteobacteria, followed by Bacteroidetes, Actinobacteria and Firmicutes. Furthermore, archaeal communities in the two samples were dominated by Thaumarchaeota and Euryarchaeota. Comparative analysis showed that (i) TVG4 displayed the higher bacterial richness and lower archaeal richness than TVG11; (ii) the two samples had more divergence in archaeal communities than bacterial communities. Bacteria and archaea that are potentially associated with nitrogen, sulfur metal and methane cycling were detected in the two samples. Overall, we first provided a comparative picture of bacterial and archaeal communities and revealed their potentially ecological roles in the deep-sea environments of inactive hydrothermal vents in the Southwest Indian Ridge, augmenting microbial communities in inactive hydrothermal vents. PMID:27169490

  6. Spatiotemporal dynamics of bacterial and archaeal communities in household biogas digesters from tropical and subtropical regions of Yunnan Province, China.

    Science.gov (United States)

    Tian, Guangliang; Li, Qiumin; Dong, Minghua; Wu, Yan; Yang, Bin; Zhang, Lijuan; Li, Yingjuan; Yin, Fang; Zhao, Xingling; Wang, Yongxia; Xiao, Wei; Cui, Xiaolong; Zhang, Wudi

    2016-06-01

    A combination of 16S rRNA gene PCR-based techniques and the determination of abiotic factors were used to study community composition, richness, and evenness and the correlation between biotic and abiotic factors in 19 household biogas digesters in tropical and subtropical regions of Yunnan Province, China. The results revealed that both bacterial and archaeal community composition differed between regions and archaeal community composition was more affected by season than bacterial; regardless of sampling location, the dominant bacterial phyla included Chloroflexi, Bacteroidetes, Firmicutes, and Proteobacteria, and the most dominant archaeal phylum was Euryarchaeota; in digesters from both regions, Chloroflexi as the first or second most dominant bacteria accounted for 21.50-26.10 % of bacterial library sequences, and the phylum Crenarchaeota as the second most dominant archaea accounted for 17.65-19.77 % of archaeal library sequences; the species Methanosaeta concilii as the most dominant archaeal species accounted for 67.80-72.80 % of the sequences. This study found that most of the abundant microbial communities in 19 biogas digesters are similar, and this result will provide enlightenment for finding the universal nature in rural biogas digesters at tropical and subtropical regions in China. PMID:26916266

  7. Phylogenetic relationship between Dermanyssus gallinae populations in European countries based on mitochondrial COI gene sequences.

    Science.gov (United States)

    Marangi, M; de Luna, C J; Cafiero, M A; Camarda, A; le Bouquin, S; Huonnic, D; Giangaspero, A; Sparagano, O A E

    2009-06-01

    Phylogenetic analysis of Dermanyssus gallinae mites originating from UK, France and Italy was performed using partial amplification of the mitochondrial COI gene. Results showed that UK samples reveal the greatest variation and diversity and are linked to one of the French populations highlighting North-South genetic transitions in European red mite populations. Intra-farm variations between mite samples highlighted the diversity between national populations and possibly its origin from the different chemical strategies used in each country. PMID:19184470

  8. Absence of phylogenetic signal in the niche structure of meadow plant communities

    OpenAIRE

    Silvertown, Jonathan; McConway, Kevin; Gowing, David; Dodd, Mike; Fay, Michael F.; Joseph, Jeffrey A.; Dolphin, Konrad

    2005-01-01

    A significant proportion of the global diversity of flowering plants has evolved in recent geological time, probably through adaptive radiation into new niches. However, rapid evolution is at odds with recent research which has suggested that plant ecological traits, including the β- (or habitat) niche, evolve only slowly. We have quantified traits that determine within-habitat α diversity (α niches) in two communities in which species segregate on hydrological gradients. Molecular phylogenet...

  9. Phylogenetic organization of bacterial activity.

    Science.gov (United States)

    Morrissey, Ember M; Mau, Rebecca L; Schwartz, Egbert; Caporaso, J Gregory; Dijkstra, Paul; van Gestel, Natasja; Koch, Benjamin J; Liu, Cindy M; Hayer, Michaela; McHugh, Theresa A; Marks, Jane C; Price, Lance B; Hungate, Bruce A

    2016-09-01

    Phylogeny is an ecologically meaningful way to classify plants and animals, as closely related taxa frequently have similar ecological characteristics, functional traits and effects on ecosystem processes. For bacteria, however, phylogeny has been argued to be an unreliable indicator of an organism's ecology owing to evolutionary processes more common to microbes such as gene loss and lateral gene transfer, as well as convergent evolution. Here we use advanced stable isotope probing with (13)C and (18)O to show that evolutionary history has ecological significance for in situ bacterial activity. Phylogenetic organization in the activity of bacteria sets the stage for characterizing the functional attributes of bacterial taxonomic groups. Connecting identity with function in this way will allow scientists to begin building a mechanistic understanding of how bacterial community composition regulates critical ecosystem functions. PMID:26943624

  10. Asperisporium and Pantospora (Mycosphaerellaceae): epitypifications and phylogenetic placement.

    Science.gov (United States)

    Minnis, A M; Kennedy, A H; Grenier, D B; Rehner, S A; Bischoff, J F

    2011-12-01

    The species-rich family Mycosphaerellaceae contains considerable morphological diversity and includes numerous anamorphic genera, many of which are economically important plant pathogens. Recent revisions and phylogenetic research have resulted in taxonomic instability. Ameliorating this problem requires phylogenetic placement of type species of key genera. We present an examination of the type species of the anamorphic Asperisporium and Pantospora. Cultures isolated from recent port interceptions were studied and described, and morphological studies were made of historical and new herbarium specimens. DNA sequence data from the ITS region and nLSU were generated from these type species, analysed phylogenetically, placed into an evolutionary context within Mycosphaerellaceae, and compared to existing phylogenies. Epitype specimens associated with living cultures and DNA sequence data are designated herein. Asperisporium caricae, the type of Asperisporium and cause of a leaf and fruit spot disease of papaya, is closely related to several species of Passalora including P. brachycarpa. The status of Asperisporium as a potential generic synonym of Passalora remains unclear. The monotypic genus Pantospora, typified by the synnematous Pantospora guazumae, is not included in Pseudocercospora sensu stricto or sensu lato. Rather, it represents a distinct lineage in the Mycosphaerellaceae in an unresolved position near Mycosphaerella microsora. PMID:22403473

  11. Phylogenetic and recombination analysis of tomato spotted wilt virus.

    Directory of Open Access Journals (Sweden)

    Sen Lian

    Full Text Available Tomato spotted wilt virus (TSWV severely damages and reduces the yield of many economically important plants worldwide. In this study, we determined the whole-genome sequences of 10 TSWV isolates recently identified from various regions and hosts in Korea. Phylogenetic analysis of these 10 isolates as well as the three previously sequenced isolates indicated that the 13 Korean TSWV isolates could be divided into two groups reflecting either two different origins or divergences of Korean TSWV isolates. In addition, the complete nucleotide sequences for the 13 Korean TSWV isolates along with previously sequenced TSWV RNA segments from Korea and other countries were subjected to phylogenetic and recombination analysis. The phylogenetic analysis indicated that both the RNA L and RNA M segments of most Korean isolates might have originated in Western Europe and North America but that the RNA S segments for all Korean isolates might have originated in China and Japan. Recombination analysis identified a total of 12 recombination events among all isolates and segments and five recombination events among the 13 Korea isolates; among the five recombinants from Korea, three contained the whole RNA L segment, suggesting reassortment rather than recombination. Our analyses provide evidence that both recombination and reassortment have contributed to the molecular diversity of TSWV.

  12. Use of EST-SSR loci flanking regions for phylogenetic analysis of genus Arachis

    Science.gov (United States)

    All wild peanut collections in the genus Arachis were assigned to nine taxonomy sections on the bases of cross-compatibility and morphologic character clustering. These nine sections consist of 80 species from the most ancient to the most advanced, providing a diverse genetic resource for phylogenet...

  13. Phylogenetic structure of plant species pools reflects habitat age on the geological time scale

    Czech Academy of Sciences Publication Activity Database

    Lososová, Z.; Šmarda, P.; Chytrý, M.; Purschke, O.; Pyšek, Petr; Sádlo, Jiří; Tichý, L.; Winter, M.

    2015-01-01

    Roč. 26, č. 6 (2015), s. 1080-1089. ISSN 1100-9233 R&D Projects: GA ČR GB14-36079G Grant ostatní: AV ČR(CZ) Praemium Academiae Institutional support: RVO:67985939 Keywords : plant communities * phylogenetic diversity * species pool Subject RIV: EH - Ecology, Behaviour Impact factor: 3.709, year: 2014

  14. Phylogenetically poor plant communities receive more alien species, which more easily coexist with natives

    Czech Academy of Sciences Publication Activity Database

    Gerhold, P.; Pärtel, M.; Tackenberg, O.; Hennekens, S.M.; Bartish, Igor; Schaminée, J.H.J.; Fergus, A. J. F.; Ozinga, W.A.; Prinzing, A.

    2011-01-01

    Roč. 177, č. 5 (2011), s. 68-680. ISSN 0003-0147 Institutional research plan: CEZ:AV0Z60050516 Keywords : species richness * phylogenetic diversity * invasions Subject RIV: EF - Botanics Impact factor: 4.725, year: 2011

  15. Alien plants invade more phylogenetically clustered community types and cause even stronger clustering

    Czech Academy of Sciences Publication Activity Database

    Lososová, Z.; de Bello, Francesco; Chytrý, M.; Kühn, I.; Pyšek, Petr; Sádlo, Jiří; Winter, M.; Zelený, D.

    2015-01-01

    Roč. 24, č. 7 (2015), s. 786-794. ISSN 1466-822X R&D Projects: GA ČR GAP505/12/1296; GA ČR GB14-36079G Institutional support: RVO:67985939 Keywords : biological invasions * phylogenetic diversity * vegetation type Subject RIV: EH - Ecology, Behaviour Impact factor: 6.531, year: 2014

  16. On the need for phylogenetic ‘corrections’ in functional trait-based approaches

    Czech Academy of Sciences Publication Activity Database

    de Bello, Francesco; Berg, M. P.; Dias, A. T. C.; Diniz-Filho, J. A. F.; Götzenberger, Lars; Hortal, J.; Ladle, L. J.; Lepš, Jan

    2015-01-01

    Roč. 50, č. 4 (2015), 349-357. ISSN 1211-9520 R&D Projects: GA ČR GAP505/12/1296; GA ČR GB14-36079G Institutional support: RVO:67985939 ; RVO:60077344 Keywords : adaptation * functional and phylogenetic diversity * limiting similarity Subject RIV: EH - Ecology, Behaviour Impact factor: 1.778, year: 2014

  17. Network dynamics of eukaryotic LTR retroelements beyond phylogenetic trees

    Directory of Open Access Journals (Sweden)

    Bernad Lucia

    2009-11-01

    Full Text Available Abstract Background Sequencing projects have allowed diverse retroviruses and LTR retrotransposons from different eukaryotic organisms to be characterized. It is known that retroviruses and other retro-transcribing viruses evolve from LTR retrotransposons and that this whole system clusters into five families: Ty3/Gypsy, Retroviridae, Ty1/Copia, Bel/Pao and Caulimoviridae. Phylogenetic analyses usually show that these split into multiple distinct lineages but what is yet to be understood is how deep evolution occurred in this system. Results We combined phylogenetic and graph analyses to investigate the history of LTR retroelements both as a tree and as a network. We used 268 non-redundant LTR retroelements, many of them introduced for the first time in this work, to elucidate all possible LTR retroelement phylogenetic patterns. These were superimposed over the tree of eukaryotes to investigate the dynamics of the system, at distinct evolutionary times. Next, we investigated phenotypic features such as duplication and variability of amino acid motifs, and several differences in genomic ORF organization. Using this information we characterized eight reticulate evolution markers to construct phenotypic network models. Conclusion The evolutionary history of LTR retroelements can be traced as a time-evolving network that depends on phylogenetic patterns, epigenetic host-factors and phenotypic plasticity. The Ty1/Copia and the Ty3/Gypsy families represent the oldest patterns in this network that we found mimics eukaryotic macroevolution. The emergence of the Bel/Pao, Retroviridae and Caulimoviridae families in this network can be related with distinct inflations of the Ty3/Gypsy family, at distinct evolutionary times. This suggests that Ty3/Gypsy ancestors diversified much more than their Ty1/Copia counterparts, at distinct geological eras. Consistent with the principle of preferential attachment, the connectivities among phenotypic markers, taken as

  18. Disturbance alters the phylogenetic composition and structure of plant communities in an old field system.

    Directory of Open Access Journals (Sweden)

    Russell Dinnage

    Full Text Available The changes in phylogenetic composition and structure of communities during succession following disturbance can give us insights into the forces that are shaping communities over time. In abandoned agricultural fields, community composition changes rapidly when a field is plowed, and is thought to reflect a relaxation of competition due to the elimination of dominant species which take time to re-establish. Competition can drive phylogenetic overdispersion, due to phylogenetic conservation of 'niche' traits that allow species to partition resources. Therefore, undisturbed old field communities should exhibit higher phylogenetic dispersion than recently disturbed systems, which should be relatively 'clustered' with respect to phylogenetic relationships. Several measures of phylogenetic structure between plant communities were measured in recently plowed areas and nearby 'undisturbed' sites. There was no difference in the absolute values of these measures between disturbed and 'undisturbed' sites. However, there was a difference in the 'expected' phylogenetic structure between habitats, leading to significantly lower than expected phylogenetic diversity in disturbed plots, and no difference from random expectation in 'undisturbed' plots. This suggests that plant species characteristic of each habitat are fairly evenly distributed on the shared species pool phylogeny, but that once the initial sorting of species into the two habitat types has occurred, the processes operating on them affect each habitat differently. These results were consistent with an analysis of correlation between phylogenetic distance and co-occurrence indices of species pairs in the two habitat types. This study supports the notion that disturbed plots are more clustered than expected, rather than 'undisturbed' plots being more overdispersed, suggesting that disturbed plant communities are being more strongly influenced by environmental filtering of conserved niche traits.

  19. Disturbance alters the phylogenetic composition and structure of plant communities in an old field system.

    Science.gov (United States)

    Dinnage, Russell

    2009-01-01

    The changes in phylogenetic composition and structure of communities during succession following disturbance can give us insights into the forces that are shaping communities over time. In abandoned agricultural fields, community composition changes rapidly when a field is plowed, and is thought to reflect a relaxation of competition due to the elimination of dominant species which take time to re-establish. Competition can drive phylogenetic overdispersion, due to phylogenetic conservation of 'niche' traits that allow species to partition resources. Therefore, undisturbed old field communities should exhibit higher phylogenetic dispersion than recently disturbed systems, which should be relatively 'clustered' with respect to phylogenetic relationships. Several measures of phylogenetic structure between plant communities were measured in recently plowed areas and nearby 'undisturbed' sites. There was no difference in the absolute values of these measures between disturbed and 'undisturbed' sites. However, there was a difference in the 'expected' phylogenetic structure between habitats, leading to significantly lower than expected phylogenetic diversity in disturbed plots, and no difference from random expectation in 'undisturbed' plots. This suggests that plant species characteristic of each habitat are fairly evenly distributed on the shared species pool phylogeny, but that once the initial sorting of species into the two habitat types has occurred, the processes operating on them affect each habitat differently. These results were consistent with an analysis of correlation between phylogenetic distance and co-occurrence indices of species pairs in the two habitat types. This study supports the notion that disturbed plots are more clustered than expected, rather than 'undisturbed' plots being more overdispersed, suggesting that disturbed plant communities are being more strongly influenced by environmental filtering of conserved niche traits. PMID:19763265

  20. Factors controlling the distribution of archaeal tetraethers in terrestrial hot springs.

    Science.gov (United States)

    Pearson, Ann; Pi, Yundan; Zhao, Weidong; Li, WenJun; Li, Yiliang; Inskeep, William; Perevalova, Anna; Romanek, Christopher; Li, Shuguang; Zhang, Chuanlun L

    2008-06-01

    Glycerol dialkyl glycerol tetraethers (GDGTs) found in hot springs reflect the abundance and community structure of Archaea in these extreme environments. The relationships between GDGTs, archaeal communities, and physical or geochemical variables are underexamined to date and when reported often result in conflicting interpretations. Here, we examined profiles of GDGTs from pure cultures of Crenarchaeota and from terrestrial geothermal springs representing a wide distribution of locations, including Yellowstone National Park (United States), the Great Basin of Nevada and California (United States), Kamchatka (Russia), Tengchong thermal field (China), and Thailand. These samples had temperatures of 36.5 to 87 degrees C and pH values of 3.0 to 9.2. GDGT abundances also were determined for three soil samples adjacent to some of the hot springs. Principal component analysis identified four factors that accounted for most of the variance among nine individual GDGTs, temperature, and pH. Significant correlations were observed between pH and the GDGTs crenarchaeol and GDGT-4 (four cyclopentane rings, m/z 1,294); pH correlated positively with crenarchaeol and inversely with GDGT-4. Weaker correlations were observed between temperature and the four factors. Three of the four GDGTs used in the marine TEX(86) paleotemperature index (GDGT-1 to -3, but not crenarchaeol isomer) were associated with a single factor. No correlation was observed for GDGT-0 (acyclic caldarchaeol): it is effectively its own variable. The biosynthetic mechanisms and exact archaeal community structures leading to these relationships remain unknown. However, the data in general show promise for the continued development of GDGT lipid-based physiochemical proxies for archaeal evolution and for paleo-ecology or paleoclimate studies. PMID:18390673