GLORIA

GEOMAR Library Ocean Research Information Access

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Osney Mead, Oxford OX2 0EL, UK : Blackwell Scientific Publications
    Molecular microbiology 17 (1995), S. 0 
    ISSN: 1365-2958
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology , Medicine
    Notes: The phase-variable PilC proteins of pathogenic Neisseria species have recently been implicated in both assembly and cellular adherence functions of the type 4 pili of these pathogens. We describe here the cloning of full-length pilC1 and pilC2 genes and the complete sequencing of the pilC2 gene of Neisseria gonorrhoeae MS11. Sequential inactivation of both genes by gene replacement in piliated (P+) variants of N. gonorrhoeae MS11 led initially to a non-piliated (P−) phenotype; however, spontaneous P+ variants could be derived from some pilC1,2 double mutants which produced morphologically intact pili. Purified pili from pilC1,2 mutants revealed no detectable PilC protein. Instead, a novel protein about 70 kDa in size appeared in the pili preparations of P+ mutants; this protein exhibited no immunological cross-reactivity with PilC1 or PilC2. We propose that this novel factor replaces the function of PilC in pilus biogenesis. Using isogenic N. gonorrhoeae strains which produce identical PilE (pilin) proteins we demonstrate that pili associated with the 70 kDa protein do not confer gonococcal adherence to human epithelial cells, in contrast to pili assembled in the presence of PilC1 or PilC2.
    Type of Medium: Electronic Resource
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    Osney Mead, Oxford OX2 0EL, UK : Blackwell Scientific Publications
    Molecular microbiology 17 (1995), S. 0 
    ISSN: 1365-2958
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology , Medicine
    Notes: Pathogenic Neisseria species, the causative agents of gonorrhoea and bacterial meningitis, encode a family of polymorphic exo-proteins which are autoproteolytically processed into several distinct extracellular components, including an IgA1 protease and an α-protein. IgA1 protease, a putative virulence determinant, is a sequence-specific endopeptidase known to cleave human IgA1, but additional target proteins have been postulated. The physical linkage of IgA1 protease and a-protein suggests a functional relationship of both precursor components. Previous work has shown that α-protein is essential neither for extracellular transport nor for the proteolytic activity of IgA1 protease. Intriguingly, α-proteins carry amino acid sequences reminiscent of nuclear location signals of viral and eukaryotic proteins. Here we demonstrate the functionality of these nuclear location signal sequences in transfected eukaryotic cells. Chimeric α-proteins show nuclear transport and selectively associate with nucleolar structures. More importantly, native purified α-proteins are capable of entering certain human primary cells from the exterior via an endocytotic route and accumulate in the nuclei. The neisserial α-proteins share several features with eukaryotic transcription factors, such as the formation of dimers via a heptad repeat sequence. We propose a role for a-proteins in the regulation of host-cell functions. As the α-proteins are covalently connected with IgA1 protease they may also serve as carriers for the IgA1 protease into human cells where additional proteolytic targets may exist. Neisseria meningitidis, which locally colonizes the nasopharyngeal mucosa of many human individuals without apparently causing symptoms, secretes this nucleus-targeted factor in large quantities.
    Type of Medium: Electronic Resource
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 3
    Publication Date: 2015-02-04
    Description: Nature Geoscience 8, 122 (2015). doi:10.1038/ngeo2349 Authors: Hanno Meyer, Thomas Opel, Thomas Laepple, Alexander Yu Dereviagin, Kirstin Hoffmann & Martin Werner Relative to the past 2,000 years, the Arctic region has warmed significantly over the past few decades. However, the evolution of Arctic temperatures during the rest of the Holocene is less clear. Proxy reconstructions, suggest a long-term cooling trend throughout the mid- to late Holocene, whereas climate model simulations show only minor changes or even warming. Here we present a record of the oxygen isotope composition of permafrost ice wedges from the Lena River Delta in the Siberian Arctic. The isotope values, which reflect winter season temperatures, became progressively more enriched over the past 7,000 years, reaching unprecedented levels in the past five decades. This warming trend during the mid- to late Holocene is in opposition to the cooling seen in other proxy records. However, most of these existing proxy records are biased towards summer temperatures. We argue that the opposing trends are related to the seasonally different orbital forcing over this interval. Furthermore, our reconstructed trend as well as the recent maximum are consistent with the greenhouse gas forcing and climate model simulations, thus reconciling differing estimates of Arctic and northern high-latitude temperature evolution during the Holocene.
    Print ISSN: 1752-0894
    Electronic ISSN: 1752-0908
    Topics: Geosciences
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 4
    Publication Date: 2016-05-29
    Description: Article Protein aggregates are associated with a wide variety of diseases. Here, in order to address how protein aggregation affects cellular homoeostasis, the authors describe a method to rapidly create protein aggregates in living cells and organisms with precise spatial and temporal control. Nature Communications doi: 10.1038/ncomms11689 Authors: Yusuke Miyazaki, Kota Mizumoto, Gautam Dey, Takamasa Kudo, John Perrino, Ling-chun Chen, Tobias Meyer, Thomas J. Wandless
    Electronic ISSN: 2041-1723
    Topics: Biology , Chemistry and Pharmacology , Natural Sciences in General , Physics
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 5
    Publication Date: 2018-11-27
    Description: Escherichia coli “Marionette” strains with 12 highly optimized small-molecule sensors 〈i〉Escherichia〈/i〉 coli “Marionette” strains with 12 highly optimized small-molecule sensors, Published online: 26 November 2018; doi:10.1038/s41589-018-0168-3 A directed evolution approach was applied to optimize a set of 12 small-molecule-responsive biosensors, which led to the engineering of “Marionette” strains of Escherichia coli incorporating these sensors for biotechnological applications.
    Print ISSN: 1552-4450
    Electronic ISSN: 1552-4469
    Topics: Biology , Chemistry and Pharmacology
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...