ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
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
    facet.materialart.
    Unknown
    Antibacterial membrane attack by a pore-forming intestinal C-type lectin (2013)
    Nature Publishing Group (NPG)
    Details
    Publication Date: 2013-11-22
    Description: Human body-surface epithelia coexist in close association with complex bacterial communities and are protected by a variety of antibacterial proteins. C-type lectins of the RegIII family are bactericidal proteins that limit direct contact between bacteria and the intestinal epithelium and thus promote tolerance to the intestinal microbiota. RegIII lectins recognize their bacterial targets by binding peptidoglycan carbohydrate, but the mechanism by which they kill bacteria is unknown. Here we elucidate the mechanistic basis for RegIII bactericidal activity. We show that human RegIIIalpha (also known as HIP/PAP) binds membrane phospholipids and kills bacteria by forming a hexameric membrane-permeabilizing oligomeric pore. We derive a three-dimensional model of the RegIIIalpha pore by docking the RegIIIalpha crystal structure into a cryo-electron microscopic map of the pore complex, and show that the model accords with experimentally determined properties of the pore. Lipopolysaccharide inhibits RegIIIalpha pore-forming activity, explaining why RegIIIalpha is bactericidal for Gram-positive but not Gram-negative bacteria. Our findings identify C-type lectins as mediators of membrane attack in the mucosal immune system, and provide detailed insight into an antibacterial mechanism that promotes mutualism with the resident microbiota.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4160023/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4160023/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Mukherjee, Sohini -- Zheng, Hui -- Derebe, Mehabaw G -- Callenberg, Keith M -- Partch, Carrie L -- Rollins, Darcy -- Propheter, Daniel C -- Rizo, Josep -- Grabe, Michael -- Jiang, Qiu-Xing -- Hooper, Lora V -- C06 RR30414/RR/NCRR NIH HHS/ -- F32 DK100074/DK/NIDDK NIH HHS/ -- GM093271/GM/NIGMS NIH HHS/ -- R01 DK070855/DK/NIDDK NIH HHS/ -- R01 NS040944/NS/NINDS NIH HHS/ -- R01 NS40944/NS/NINDS NIH HHS/ -- R01GM088745/GM/NIGMS NIH HHS/ -- Howard Hughes Medical Institute/ -- England -- Nature. 2014 Jan 2;505(7481):103-7. doi: 10.1038/nature12729. Epub 2013 Nov 20.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Immunology, The University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA. ; Department of Cell Biology, The University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA. ; Department of Biological Sciences, University of Pittsburgh, and Joint Carnegie Mellon University-University of Pittsburgh PhD Program in Computational Biology, Pittsburgh, Pennsylvania 15261, USA. ; Department of Chemistry and Biochemistry, University of California, Santa Cruz, California 95064, USA. ; Department of Biochemistry and Department of Pharmacology, The University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA. ; 1] Department of Biological Sciences, University of Pittsburgh, and Joint Carnegie Mellon University-University of Pittsburgh PhD Program in Computational Biology, Pittsburgh, Pennsylvania 15261, USA [2] Cardiovascular Research Institute, University of California, San Francisco, San Francisco, California 94143, USA. ; 1] Department of Cell Biology, The University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA [2]. ; 1] Department of Immunology, The University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA [2] The Howard Hughes Medical Institute, The University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA [3].〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/24256734" target="_blank"〉PubMed〈/a〉
    Keywords: Anti-Bacterial Agents/chemistry/immunology/*metabolism/pharmacology ; Antigens, Neoplasm/chemistry/immunology/*metabolism ; Biomarkers, Tumor/antagonists & inhibitors/chemistry/immunology/*metabolism ; Cell Membrane Permeability/drug effects ; Cryoelectron Microscopy ; Crystallography, X-Ray ; Gram-Negative Bacteria/drug effects/immunology/metabolism ; Humans ; Immunity, Mucosal/drug effects/immunology ; Intestines/*chemistry/immunology/microbiology ; Lectins, C-Type/antagonists & inhibitors/chemistry/immunology/*metabolism ; Lipopolysaccharides/pharmacology ; Listeria monocytogenes/drug effects/immunology/metabolism ; Microbial Viability/drug effects ; Models, Molecular ; Peptidoglycan/metabolism ; Phospholipids/metabolism ; Porins/antagonists & inhibitors/chemistry/*metabolism ; Symbiosis
    Print ISSN: 0028-0836
    Electronic ISSN: 1476-4687
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Published by Nature Publishing Group (NPG)
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 2
    facet.materialart.
    Unknown
    Crystal structure of a potassium ion transporter, TrkH (2011)
    Nature Publishing Group (NPG)
    Details
    Publication Date: 2011-02-15
    Description: The TrkH/TrkG/KtrB proteins mediate K(+) uptake in bacteria and probably evolved from simple K(+) channels by multiple gene duplications or fusions. Here we present the crystal structure of a TrkH from Vibrio parahaemolyticus. TrkH is a homodimer, and each protomer contains an ion permeation pathway. A selectivity filter, similar in architecture to those of K(+) channels but significantly shorter, is lined by backbone and side-chain oxygen atoms. Functional studies showed that TrkH is selective for permeation of K(+) and Rb(+) over smaller ions such as Na(+) or Li(+). Immediately intracellular to the selectivity filter are an intramembrane loop and an arginine residue, both highly conserved, which constrict the permeation pathway. Substituting the arginine with an alanine significantly increases the rate of K(+) flux. These results reveal the molecular basis of K(+) selectivity and suggest a novel gating mechanism for this large and important family of membrane transport proteins.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3077569/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3077569/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Cao, Yu -- Jin, Xiangshu -- Huang, Hua -- Derebe, Mehabaw Getahun -- Levin, Elena J -- Kabaleeswaran, Venkataraman -- Pan, Yaping -- Punta, Marco -- Love, James -- Weng, Jun -- Quick, Matthias -- Ye, Sheng -- Kloss, Brian -- Bruni, Renato -- Martinez-Hackert, Erik -- Hendrickson, Wayne A -- Rost, Burkhard -- Javitch, Jonathan A -- Rajashankar, Kanagalaghatta R -- Jiang, Youxing -- Zhou, Ming -- DK088057/DK/NIDDK NIH HHS/ -- GM05026/GM/NIGMS NIH HHS/ -- GM05026-SUB0007/GM/NIGMS NIH HHS/ -- HL086392/HL/NHLBI NIH HHS/ -- K05 DA022413/DA/NIDA NIH HHS/ -- P30 EB009998/EB/NIBIB NIH HHS/ -- R01 DK088057/DK/NIDDK NIH HHS/ -- R01 DK088057-01/DK/NIDDK NIH HHS/ -- R01 HL086392/HL/NHLBI NIH HHS/ -- R01 HL086392-05/HL/NHLBI NIH HHS/ -- Howard Hughes Medical Institute/ -- England -- Nature. 2011 Mar 17;471(7338):336-40. doi: 10.1038/nature09731. Epub 2011 Feb 13.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Physiology & Cellular Biophysics, College of Physicians and Surgeons, Columbia University, 630 West 168th Street, New York, New York 10032, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/21317882" target="_blank"〉PubMed〈/a〉
    Keywords: ATP-Binding Cassette Transporters/chemistry ; Amino Acid Sequence ; Crystallography, X-Ray ; Escherichia coli Proteins/chemistry ; Ion Channel Gating ; Ion Transport ; Models, Molecular ; Molecular Sequence Data ; Potassium/metabolism ; Potassium Channels/*chemistry/*metabolism ; Structure-Activity Relationship ; Substrate Specificity ; Vibrio parahaemolyticus/*chemistry
    Print ISSN: 0028-0836
    Electronic ISSN: 1476-4687
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Published by Nature Publishing Group (NPG)
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 3
    facet.materialart.
    Unknown
    Structural studies of ion permeation and Ca2+ blockage of a bacterial channel mimicking the cyclic nucleotide-gated channel pore (2010)
    National Academy of Sciences
    Details
    Publication Date: 2010-12-27
    Print ISSN: 0027-8424
    Electronic ISSN: 1091-6490
    Topics: Biology , Medicine , Natural Sciences in General
    Published by National Academy of Sciences
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 4
    facet.materialart.
    Unknown
    Tuning the ion selectivity of tetrameric cation channels by changing the number of ion binding sites (2010)
    National Academy of Sciences
    Details
    Publication Date: 2010-12-27
    Print ISSN: 0027-8424
    Electronic ISSN: 1091-6490
    Topics: Biology , Medicine , Natural Sciences in General
    Published by National Academy of Sciences
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 5
    facet.materialart.
    Unknown
    Structural studies of ion permeation and Ca2+ blockage of a bacterial channel mimicking the cyclic nucleotide-gated channel pore [Biophysics and Computational Biology] (2011)
    National Academy of Sciences
    Details
    Publication Date: 2011-01-12
    Description: Cyclic nucleotide-gated (CNG) channels play an essential role in the visual and olfactory sensory systems and are ubiquitous in eukaryotes. Details of their underlying ion selectivity properties are still not fully understood and are a matter of debate in the absence of high-resolution structures. To reveal the structural mechanism of ion selectivity in CNG channels, particularly their Ca2+ blockage property, we engineered a set of mimics of CNG channel pores for both structural and functional analysis. The mimics faithfully represent the CNG channels they are modeled after, permeate Na+ and K+ equally well, and exhibit the same Ca2+ blockage and permeation properties. Their high-resolution structures reveal a hitherto unseen selectivity filter architecture comprising three contiguous ion binding sites in which Na+ and K+ bind with different ion-ligand geometries. Our structural analysis reveals that the conserved acidic residue in the filter is essential for Ca2+ binding but not through direct ion chelation as in the currently accepted view. Furthermore, structural insight from our CNG mimics allows us to pinpoint equivalent interactions in CNG channels through structure-based mutagenesis that have previously not been predicted using NaK or K+ channel models.
    Print ISSN: 0027-8424
    Electronic ISSN: 1091-6490
    Topics: Biology , Medicine , Natural Sciences in General
    Published by National Academy of Sciences
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 6
    facet.materialart.
    Unknown
    Tuning the ion selectivity of tetrameric cation channels by changing the number of ion binding sites [Biophysics and Computational Biology] (2011)
    National Academy of Sciences
    Details
    Publication Date: 2011-01-12
    Description: Selective ion conduction across ion channel pores is central to cellular physiology. To understand the underlying principles of ion selectivity in tetrameric cation channels, we engineered a set of cation channel pores based on the nonselective NaK channel and determined their structures to high resolution. These structures showcase an ensemble of selectivity filters with a various number of contiguous ion binding sites ranging from 2 to 4, with each individual site maintaining a geometry and ligand environment virtually identical to that of equivalent sites in K+ channel selectivity filters. Combined with single channel electrophysiology, we show that only the channel with four ion binding sites is K+ selective, whereas those with two or three are nonselective and permeate Na+ and K+ equally well. These observations strongly suggest that the number of contiguous ion binding sites in a single file is the key determinant of the channel’s selectivity properties and the presence of four sites in K+ channels is essential for highly selective and efficient permeation of K+ ions.
    Print ISSN: 0027-8424
    Electronic ISSN: 1091-6490
    Topics: Biology , Medicine , Natural Sciences in General
    Published by National Academy of Sciences
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 7
    facet.materialart.
    Unknown
    Synthesis and crystal structure of diaquabis(diketohydrindene-diketohydrindamine)manganese(II) (2003)
    De Gruyter
    Details
    Publication Date: 2003-01-01
    Description: Diaquabis(diketohydrindene-diketohydrindamine)manganese(II), Mn(II) complex of Ruhemann's purple, a condensation product of ninhydrin and
    Print ISSN: 2194-4946
    Electronic ISSN: 2196-7105
    Topics: Geosciences , Physics
    Published by De Gruyter
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...