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1.
Phenotype ontologies are typically constructed to serve the needs of a particular community, such as annotation of genotype-phenotype associations in mouse or human. Here we demonstrate how these ontologies can be improved through assignment of logical definitions using a core ontology of phenotypic qualities and multiple additional ontologies from the Open Biological Ontologies library. We also show how these logical definitions can be used for data integration when combined with a unified multi-species anatomy ontology.  相似文献   
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Over the recent years, next generation sequencing and microarray technologies have revolutionized scientific research with their applications to high-throughput analysis of biological systems. Isolation of high quantities of pure, intact, double stranded, highly concentrated, not contaminated genomic DNA is prerequisite for successful and reliable large scale genotyping analysis. High quantities of pure DNA are also required for the creation of DNA-banks. In the present study, eleven different DNA extraction procedures, including phenol-chloroform, silica and magnetic beads based extractions, were examined to ascertain their relative effectiveness for extracting DNA from ovine blood samples. The quality and quantity of the differentially extracted DNA was subsequently assessed by spectrophotometric measurements, Qubit measurements, real-time PCR amplifications and gel electrophoresis. Processing time, intensity of labor and cost for each method were also evaluated. Results revealed significant differences among the eleven procedures and only four of the methods yielded satisfactory outputs. These four methods, comprising three modified silica based commercial kits (Modified Blood, Modified Tissue, Modified Dx kits) and an in-house developed magnetic beads based protocol, were most appropriate for extracting high quality and quantity DNA suitable for large-scale microarray genotyping and also for long-term DNA storage as demonstrated by their successful application to 600 individuals.  相似文献   
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The aim of this study was to investigate the impact of early colonizing species on the structure and the composition of the bacterial community developing in a subgingival 10-species biofilm model system. The model included Streptococcus oralis, Streptococcus anginosus, Actinomycesoris, Fusobacterium nucleatum subsp. nucleatum, Veillonella dispar, Campylobacter rectus, Prevotella intermedia, Porphyromonas gingivalis, Tannerella forsythia, and Treponema denticola. Based on literature, we considered Streptococcus oralis, Streptococcus anginosus, and Actinomyces oris as early colonizers and examined their role in the biofilms by either a delayed addition to the consortium, or by not inoculating at all the biofilms with these species. We quantitatively evaluated the resulting biofilms by real-time quantitative PCR and further compared the structures using confocal laser scanning microscopy following fluorescence in situ hybridisation. The absence of the early colonizers did not hinder biofilm formation. The biofilms reached the same total counts and developed to normal thickness. However, quantitative shifts in the abundances of individual species were observed. In the absence of streptococci, the overall biofilm structure appeared looser and more dispersed. Moreover, besides a significant increase of P. intermedia and a decrease of P. gingivalis , P. intermedia appeared to form filamented long chains that resembled streptococci. A. oris, although growing to significantly higher abundance in absence of streptococci, did not have a visible impact on the biofilms. Hence, in the absence of the early colonizers, there is a pronounced effect on P. intermedia and P. gingivalis that may cause distinct shifts in the structure of the biofilm. Streptococci possibly facilitate the establishment of P. gingivalis into subgingival biofilms, while in their absence P. intermedia became more dominant and forms elongated chains.  相似文献   
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Background

The interaction between gut bacterial symbionts and Tephritidae became the focus of several studies that showed that bacteria contributed to the nutritional status and the reproductive potential of its fruit fly hosts. Anastrepha fraterculus is an economically important fruit pest in South America. This pest is currently controlled by insecticides, which prompt the development of environmentally friendly methods such as the sterile insect technique (SIT). For SIT to be effective, a deep understanding of the biology and sexual behavior of the target species is needed. Although many studies have contributed in this direction, little is known about the composition and role of A. fraterculus symbiotic bacteria. In this study we tested the hypothesis that gut bacteria contribute to nutritional status and reproductive success of A. fraterculus males.

Results

AB affected the bacterial community of the digestive tract of A. fraterculus, in particular bacteria belonging to the Enterobacteriaceae family, which was the dominant bacterial group in the control flies (i.e., non-treated with AB). AB negatively affected parameters directly related to the mating success of laboratory males and their nutritional status. AB also affected males’ survival under starvation conditions. The effect of AB on the behaviour and nutritional status of the males depended on two additional factors: the origin of the males and the presence of a proteinaceous source in the diet.

Conclusions

Our results suggest that A. fraterculus males gut contain symbiotic organisms that are able to exert a positive contribution on A. fraterculus males’ fitness, although the physiological mechanisms still need further studies.

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Fungal chitinases are hydrolytic enzymes responsible for degradation of chitin. Chitinases are involved in several aspects of fungal biology, including cell wall remodelling during hyphal growth, conidial germination, autolysis, mycoparasitism and nutrient acquisition. They are divided into three distinct phylogenetic groups; A, B and C. Chitinases from the C group show structural similarities with the killer toxin zymocin produced by the yeast Kluyveromyces lactis and it is speculated that they have a similar function in filamentous ascomycetes, by facilitating penetration of toxins into cells of competing individuals. Genome analyses show that certain fungal species with a mycoparasitic lifestyle contain high numbers of killer toxin-like chitinases, compared with specialized saprotrophs and plant pathogens. Recent developments within this research field have revealed considerable variation in the modular structure and regulation of killer toxin-like chitinases, suggesting more diverse roles than merely fungal-fungal interactions. In this review, we summarize the current knowledge about this intriguing class of chitinases, including their modular structure, evolution, gene regulation, and functional analyses in mycoparasitic as well as in saprotrophic species. We also propose important questions for future research.  相似文献   
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Thymus sibthorpii Benth. (Lamiaceae), with accession number 01,1796-22, is a biotype of native Greek thyme with ascending stems and potential use as a new medicinal-aromatic crop and ornamental plant. An efficient and reliable protocol for in vitro clonal propagation of T. sibthorpii from nodes and meristem tip explants was developed. Shoot proliferation succeeded on a new basal medium (BB) without plant growth regulators, as prior experiments with 6-benzyladenine generated hyperhydricity. Eight different basal media were compared; on two formulations using the new BB 5.9 and 5.6 shoots per explant were produced. Regenerated single shoots were rooted in the BB medium, supplemented with 5 μM of indole-3-butyric acid, and produced 3.1 roots along with 2.5 adventitious shoots. Three types of acclimatization were assessed: in vitro, using two different systems (no significant differences); ex vitro, using eight soil substrates under greenhouse and outdoor nursery conditions (in two of them, 100% of plantlets survived); and in field cultivations, established at eight geographically distant areas of Greece (100% survival rate at all locations). Molecular characterization of T. sibthorpii was evaluated with one nuclear ribosomal DNA and seven chloroplast DNA markers, followed by DNA sequence comparisons with a total of 30 different Thymus species, subspecies, and varieties. The trnH/psbA, trnL/trnF, and matK genes were the most efficient markers for molecular characterization of T. sibthorpii. The molecular markers rpoC1 and petB/petD did not match to any Thymus species and therefore, these DNA sequences provide new sequence information for entire Thymus taxa.

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