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161.
Kuryshev VY Vorobyov E Zink D Schmitz J Rozhdestvensky TS Münstermann E Ernst U Wellenreuther R Moosmayer P Bechtel S Schupp I Horst J Korn B Poustka A Wiemann S 《Genomics》2006,88(2):143-151
Segmental duplications (SDs) play a key role in genome evolution by providing material for gene diversification and creation of variant or novel functions. They also mediate recombinations, resulting in microdeletions, which have occasionally been associated with human genetic diseases. Here, we present a detailed analysis of a large genomic region (about 240 kb), located on human chromosome 1q22, that contains a tandem SD, SD1q22. This duplication occurred about 37 million years ago in a lineage leading to anthropoid primates, after their separation from prosimians but before the Old and New World monkey split. We reconstructed the hypothetical unduplicated ancestral locus and compared it with the extant SD1q22 region. Our data demonstrate that, as a consequence of the duplication, new anthropoid-specific genetic material has evolved in the resulting paralogous segments. We describe the emergence of two new genes, whose new functions could contribute to the speciation of anthropoid primates. Moreover, we provide detailed information regarding structure and evolution of the SD1q22 region that is a prerequisite for future studies of its anthropoid-specific functions and possible linkage to human genetic disorders. 相似文献
162.
163.
Joanne M. Munck Alison M. Motley James M. Nuttall Ewald H. Hettema 《The Journal of cell biology》2009,187(4):463-471
Saccharomyces cerevisiae Pex3p has been shown to act at the ER during de novo peroxisome formation. However, its steady state is at the peroxisomal membrane, where its role is debated. Here we show that Pex3p has a dual function: one in peroxisome formation and one in peroxisome segregation. We show that the peroxisome retention factor Inp1p interacts physically with Pex3p in vitro and in vivo, and split-GFP analysis shows that the site of interaction is the peroxisomal membrane. Furthermore, we have generated PEX3 alleles that support peroxisome formation but fail to support recruitment of Inp1p to peroxisomes, and as a consequence are affected in peroxisome segregation. We conclude that Pex3p functions as an anchor for Inp1p at the peroxisomal membrane, and that this function is independent of its role at the ER in peroxisome biogenesis. 相似文献
164.
Nicole Kronberger Peter Holtz Wolfgang Kerbe Ewald Strasser Wolfgang Wagner 《Systems and synthetic biology》2009,3(1-4):19-26
We present insights from a study on communicating Synthetic Biology conducted in 2008. Scientists were invited to write press releases on their work; the resulting texts were passed on to four journalists from major Austrian newspapers and magazines. The journalists in turn wrote articles that were used as stimulus material for eight group discussions with select members of the Austrian public. The results show that, from the lab via the media to the general public, communication is characterized by two important tendencies: first, communication becomes increasingly focused on concrete applications of Synthetic Biology; and second, biotechnology represents an important benchmark against which Synthetic Biology is being evaluated. 相似文献
165.
A new species Ganoderma carocalcareus (Basidiomycota, Ganodermataceae) was collected on living trunk and dead stumps of Anthocleista nobilis (Gentianaceae) in waterlogged swamps in the Mbalmayo Forest Reserve, Cameroon, and identified on the basis of morphology
and phylogenetic analyses inferred from mitochondrial small subunit (mtSSU) and internal transcribed spacer (ITS1-5.8S-ITS2)
rDNA sequences. Distinct phenotypic characteristics of the new species are dimorphism of basidiomata and variability in context
structure and texture over developmental stages. The young basidiomata is ungulate to punk-shaped with context composed of
vegetative hyphae attended by scattered, orbicular, smooth, thick-walled chlamydospores, and the mature basidiomata is cushion-
to bracket-like with context entirely consisting of chlamydospores masses. This ontogeny intimates the origin of chlamydospores,
for which the biogenesis correlates the vanishing of vegetative hyphae throughout the basidiomata maturation. Morphological
comparison included Tomophagus colossus (=G. colossus), G. subamboinense and G. weberianum, the known Ganodermataceae species producing chlamydospores and or gasterospores in basidiomata tissues, and G. resinaceum, the closest species with regard to morphology. It followed that G. carocalcareus could not be assigned to these or any other known Ganoderma species. Analyses of mtSSU and ITS rDNA sequence data resolved G. carocalcareus in the G. resinaceum group as a distinct species, but being a close relative of both G. subamboinense and G. weberianum. 相似文献
166.
Anzar A. Khuroo Ewald Weber Akhtar H. Malik G. H. Dar Zafar A. Reshi 《Nordic Journal of Botany》2010,28(6):685-696
Biodiversity inventories unravel insightful taxonomic and biogeographic patterns that provide valuable inputs in guiding conservation practices and policymaking. Here we present an updated inventory of the native and alien woody flora of the Kashmir Himalaya, India, together with analyses of the patterns of taxonomic composition, geographic distribution, and invasion status of the alien species. The data was assembled from the floristic literature of the last two centuries, supplemented with herbarium records and validated by field surveys over the past decade. In total, the woody flora comprised of 520 species; out of these 322 species were native and 198 alien, yielding a proportion of 38% aliens. Amongst the natives, 16 species are on the IUCN red list 2009. While 37 genera included both native and alien species indicating a potential for hybrid formation, only 15 families were represented by alien species exclusively. Regarding the invasion status, presently 37 alien woody species are naturalized and 7 are invasive in the region. The results show that the Kashmir Himalaya harbours a diverse woody flora. It is concluded that a distinction between the native and the alien flora, as adopted in the present study, is crucial for a meaningful analysis of any biodiversity patterns. We predict that in the near future many alien woody species, presently naturalized in the region, can become serious plant invaders, and therefore need further research efforts and timely management. 相似文献
167.
Antimicrobial titanium/silver PVD coatings on titanium 总被引:1,自引:0,他引:1
Andrea Ewald Susanne K Glückermann Roger Thull Uwe Gbureck 《Biomedical engineering online》2006,5(1):22-10
Background
Biofilm formation and deep infection of endoprostheses is a recurrent complication in implant surgery. Post-operative infections may be overcome by adjusting antimicrobial properties of the implant surface prior to implantation. In this work we described the development of an antimicrobial titanium/silver hard coating via the physical vapor deposition (PVD) process. 相似文献168.
Semen samples from 100 beef breed bulls were evaluated for sperm morphology (phased contrast microscopy), seminal white blood cells, and the presence of potential reproductive pathogens. Eligibility required visualization of the glans penis throughout semen collection. Based on clinical spermiograms, bulls were grouped into normal, marginal, or unsatisfactory morphology classifications. The 3 experimental groups were similar in age and scrotal circumference and differed significantly in the percentage of primary sperm abnormalities. Most semen samples (94%) contained one or more potential reproductive pathogens (Hemophilus somnus. Mycoplasma bovigenitalium, Arcanobacterium pyogenes and Ureaplasma diversum). No significant relationship could be demonstrated between primary abnormalities and the assigned culture score. Our experimental results suggest that clinicians should interpret clinical semen culture results with great care. No significant relationship could be demonstrated between primary abnormalities and assigned white blood cell (WBC) score, although, only 1% of the samples was scored >5 WBC per high power field. The use of seminal WBC score may be valid adjunct to routine semen evaluation when that threshold is the basis for clinical decisions. 相似文献
169.
170.
Ewald Sprecher 《Archives of microbiology》1961,38(4):299-325
Zusammenfassung An den beiden Ascomyceten Endoconidiophora virescens Davids. und E. (Ceratocystis) coerulescens Münch, sowie an dem Basidiomyceten Lentinus lepideus L. wurden Synthese und Ausscheidung sekundärer Stoffwechselprodukte untersucht.Am Beispiel des mit den Terpenen verwandten Methylheptenon und des p-Methoxyzimtsäuremethylesters sowie eines aromatischen Farbstoffes ließ sich zeigen, daß diese chemisch und hinsichtlich des Biosyntheseweges verschiedenen Verbindungen im overflow metabolism entstehen und ausgeschieden werden.Gegenüber den primären Stoffwechselprodukten lassen sich Biogenese und Ausscheidung der sekundären Stoffe wesentlich stärker beeinflussen. Unter gewissen Bedingungen kann sogar die Synthese bestimmter Verbindungen völlig unterbleiben.Eine nennenswerte antibiotische oder wesentliche metabolische Aktivität ausgeschiedener Stoffwechselprodukte liegt bei den drei Pilzen nicht vor.Die Ergebnisse wurden mit den Befunden anderer Autoren verglichen und die gemeinsamen Grundlagen aller pflanzlichen Stoffausscheidungen diskutiert.Habilitationsschrift (gekürzt) der Fakultät für Natur- und Geisteswissenschaften, Technische Hochschule, Karlsruhe. Tei II. 相似文献