14 resultados para follower accession

em Publishing Network for Geoscientific


Relevância:

20.00% 20.00%

Publicador:

Resumo:

Metabolomic analysis has shown the chemical richness of the sponge-associated actinomycetes Streptomyces sp. SBT349, Nonomureae sp. SBT364, and Nocardiopsis sp. SBT366. The genomes of these actinomycetes were sequenced and the genomic potential for secondary metabolism was evaluated. Their draft genomes have sizes of 8.0, 10, and 5.8Mb having 687, 367, and 179 contigs with a GC content of 71.6, 70.7, and 72.7%, respectively. Moreover, antiSMASH 3.0 predicted 108, 149, and 75 secondary metabolite gene clusters, respectively which highlight the metabolic capacity of the three actinomycete species to produce diverse classes of natural products.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Here, we report the draft genome sequences of three actinobacterial isolates, Micromonospora sp. RV43, Rubrobacter sp. RV113, and Nocardiopsis sp. RV163 that had previously been isolated from Mediterranean sponges. The draft genomes were analyzed for the presence of gene clusters indicative of secondary metabolism using antiSMASH 3.0 and NapDos pipelines. Our findings demonstrated the chemical richness of sponge-associated actinomycetes and the efficacy of genome mining in exploring the genomic potential of sponge-derived actinomycetes.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Based on our current knowledge about population genetics, phylogeography and speciation, we begin to understand that the deep sea harbours more species than suggested in the past. Deep-sea soft-sediment environment in particular hosts a diverse and highly endemic invertebrate fauna. Very little is known about evolutionary processes that generate this remarkable species richness, the genetic variability and spatial distribution of deep-sea animals. In this study, phylogeographic patterns and the genetic variability among eight populations of the abundant and widespread deep-sea isopod morphospecies Betamorpha fusiformis [Barnard, K.H., 1920. Contributions to the crustacean fauna of South Africa. 6. Further additions to the list of marine isopods. Annals of the South African Museum 17, 319-438] were examined. A fragment of the mitochondrial 16S rRNA gene of 50 specimens and the complete nuclear 18S rRNA gene of 7 specimens were sequenced. The molecular data reveal high levels of genetic variability of both genes between populations, giving evidence for distinct monophyletic groups of haplotypes with average p-distances ranging from 0.0470 to 0.1440 (d-distances: 0.0592-0.2850) of the 16S rDNA, and 18S rDNA p-distances ranging between 0.0032 and 0.0174 (d-distances: 0.0033-0.0195). Intermediate values are absent. Our results show that widely distributed benthic deep-sea organisms of a homogeneous phenotype can be differentiated into genetically highly divergent populations. Sympatry of some genotypes indicates the existence of cryptic speciation. Flocks of closely related but genetically distinct species probably exist in other widespread benthic deep-sea asellotes and other Peracarida. Based on existing data we hypothesize that many widespread morphospecies are complexes of cryptic biological species (patchwork hypothesis).

Relevância:

10.00% 10.00%

Publicador:

Resumo:

We studied polar and temperate samples of the lichen Cetraria aculeata to investigate whether genetical differences between photobionts are correlated with physiological properties of the lichen holobiont. Net photosynthesis and dark respiration (DR) at different temperatures (from 0 to 30 °C) and photon flux densities (from 0 to 1,200 ?mol/m**2/s) were studied for four populations of Cetraria aculeata. Samples were collected from maritime Antarctica, Svalbard, Germany and Spain, representing different climatic situations. Sequencing of the photobiont showed that the investigated samples fall in the polar and temperate clade described in Fernández-Mendoza et al. (2011, doi:10.1111/j.1365-294X.2010.04993.x). Lichens with photobionts from these clades differ in their temperature optimum for photosynthesis, maximal net photosynthesis, maximal DR and chlorophyll content. Maximal net photosynthesis was much lower in Antarctica and Svalbard than in Germany and Spain. The difference was smaller when rates were expressed by chlorophyll content. The same is true for the temperature optima of polar (11 °C) and temperate (15 and 17 °C) lichens. Our results indicate that lichen mycobionts may adapt or acclimate to local environmental conditions either by selecting algae from regional pools or by regulating algal cell numbers (chlorophyll content) within the thallus.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

This study focused on the bacterial diversity associated with microbial mats of deep-sea cold seeps at the Norwegian continental margin. Study sites included the Storegga and Nyegga areas as well as the Håkon Mosby mud volcano, where the mats occurred at temperatures permanently close to the freezing point of seawater. Two visually different mat types, i.e. small gray mats and extensive white mats, were studied with the aim to determine the identity of the mat-forming sulfide oxidizers, and to investigate which environmental factors (e.g. sulfate reduction and methane oxidation rates) shown here could explain the observed diversity. Sequence data have been submitted to the EMBL database under accession No. FR847864-FR847887 (giant sulfur bacteria), No. FR827864 (Menez Gwen filament; see Supplementary Material) and No. FR875365-FR877509 (except FR875905; remaining partial sequences).

Relevância:

10.00% 10.00%

Publicador:

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Large vesicomyid clams are common inhabitants of sulphidic deep-sea habitats such as hydrothermal vents, hydrocarbon seeps and whale-falls. Yet, the species- and genus-level taxonomy of these diverse clams has been unstable due to insufficiencies in sampling and absence of detailed taxonomic studies that would consistently compare molecular and morphological characters. To clarify uncertainties about species-level assignments, we examined DNA sequences from mitochondrial cytochrome-c-oxidase subunit I (COI) in conjunction with morphological characters. New and published COI sequences were used to create a molecular database for 44 unique evolutionary lineages corresponding to species. Overall, the congruence between molecular and morphological characters was good. Several discrepancies due to synonymous species designations were recognized, and acceptable species names were rectified with published COI sequences in cases where morphological specimens were available. We identified seven species with trans-Pacific distributions, and two species with Indo-Pacific distributions. Presently, 27 species have only been documented from one region, which might reflect limited ranges, or insufficient geographical sampling. Vesicomyids exhibit the greatest species diversity along the northwest Pacific ridge systems and in the eastern Pacific, along the western America margin, where depth zonation typically results in segregation of closely related species. The broad distributions of several vesicomyid species suggest that their required chemosynthetic habitats might be more common than previously recognized and occur along most continental margins.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Microorganisms play an important role in the transformation of material within the earth's crust. The storage of CO2 could affect the composition of inorganic and organic components in the reservoir, consequently influencing microbial activities. To study the microbial induced processes together with geochemical, petrophysical and mineralogical changes, occurring during CO2 storage, long-term laboratory experiments under simulated reservoir P-T conditions were carried out. Clean inner core sections, obtained from the reservoir region at the CO2 storage site in Ketzin (Germany) from a depth of about 650 m, were incubated in high pressure vessels together with sterile synthetic formation brine under in situ P-T conditions of 5.5 MPa and 40°C. A 16S rDNA based fingerprinting method was used to identify the dominant species in DNA extracts of pristine sandstone samples. Members of the alpha- and beta-subdivisions of Proteobacteria and the Actinobacteria were identified. So far sequences belonging to facultative anaerobic, chemoheterotrophic bacteria (Burkholderia fungorum, Agrobacterium tumefaciens) gaining their energy from the oxidation of organic molecules and a genus also capable of chemolithoautotrophic growth (Hydrogenophaga) was identified. During CO2 incubation minor changes in the microbial community composition were observed. The majority of microbes were able to adapt to the changed conditions. During CO2 exposure increased concentrations of Ca**2+, K**+, Mg**2+ and SO4**2- were observed. Partially, concentration rises are (i) due to equilibration between rock pore water and synthetic brine, and (ii) between rock and brine, and are thus independent on CO2 exposure. However, observed concentrations of Ca**2+, K**+, Mg**2+ are even higher than in the original reservoir fluid and therefore indicate mineral dissolution due to CO2 exposure.