ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

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
    Publication Date: 2015-07-30
    Description: DNA replication in eukaryotes is strictly regulated by several mechanisms. A central step in this replication is the assembly of the heterohexameric minichromosome maintenance (MCM2-7) helicase complex at replication origins during G1 phase as an inactive double hexamer. Here, using cryo-electron microscopy, we report a near-atomic structure of the MCM2-7 double hexamer purified from yeast G1 chromatin. Our structure shows that two single hexamers, arranged in a tilted and twisted fashion through interdigitated amino-terminal domain interactions, form a kinked central channel. Four constricted rings consisting of conserved interior beta-hairpins from the two single hexamers create a narrow passageway that tightly fits duplex DNA. This narrow passageway, reinforced by the offset of the two single hexamers at the double hexamer interface, is flanked by two pairs of gate-forming subunits, MCM2 and MCM5. These unusual features of the twisted and tilted single hexamers suggest a concerted mechanism for the melting of origin DNA that requires structural deformation of the intervening DNA.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Li, Ningning -- Zhai, Yuanliang -- Zhang, Yixiao -- Li, Wanqiu -- Yang, Maojun -- Lei, Jianlin -- Tye, Bik-Kwoon -- Gao, Ning -- England -- Nature. 2015 Aug 13;524(7564):186-91. doi: 10.1038/nature14685. Epub 2015 Jul 29.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Ministry of Education Key Laboratory of Protein Sciences, Center for Structural Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China. ; 1] Division of Life Science, Hong Kong Universityof Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China [2] Institute for Advanced Study, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China. ; 1] Division of Life Science, Hong Kong Universityof Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China [2] Department of Molecular Biology and Genetics, College of Agriculture and Life Sciences, Cornell University, Ithaca, New York 14853, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/26222030" target="_blank"〉PubMed〈/a〉
    Keywords: Binding Sites ; Cell Cycle Proteins/chemistry/metabolism/ultrastructure ; Chromatin/chemistry ; Conserved Sequence ; *Cryoelectron Microscopy ; DNA/chemistry/metabolism/ultrastructure ; DNA-Directed DNA Polymerase/chemistry/ultrastructure ; G1 Phase ; Minichromosome Maintenance Proteins/*chemistry/metabolism/*ultrastructure ; Models, Biological ; Models, Molecular ; Multienzyme Complexes/chemistry/ultrastructure ; Nucleic Acid Denaturation ; Protein Binding ; Protein Multimerization ; Protein Structure, Tertiary ; Protein Subunits/*chemistry/metabolism ; Replication Origin ; Saccharomyces cerevisiae/*chemistry/*ultrastructure ; Saccharomyces cerevisiae Proteins/chemistry/metabolism/ultrastructure
    Print ISSN: 0028-0836
    Electronic ISSN: 1476-4687
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    Publication Date: 2016-02-24
    Description: All Gram-negative bacteria, mitochondria and chloroplasts have outer membrane proteins (OMPs) that perform many fundamental biological processes. The OMPs in Gram-negative bacteria are inserted and folded into the outer membrane by the beta-barrel assembly machinery (BAM). The mechanism involved is poorly understood, owing to the absence of a structure of the entire BAM complex. Here we report two crystal structures of the Escherichia coli BAM complex in two distinct states: an inward-open state and a lateral-open state. Our structures reveal that the five polypeptide transport-associated domains of BamA form a ring architecture with four associated lipoproteins, BamB-BamE, in the periplasm. Our structural, functional studies and molecular dynamics simulations indicate that these subunits rotate with respect to the integral membrane beta-barrel of BamA to induce movement of the beta-strands of the barrel and promote insertion of the nascent OMP.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Gu, Yinghong -- Li, Huanyu -- Dong, Haohao -- Zeng, Yi -- Zhang, Zhengyu -- Paterson, Neil G -- Stansfeld, Phillip J -- Wang, Zhongshan -- Zhang, Yizheng -- Wang, Wenjian -- Dong, Changjiang -- G1100110/1/Medical Research Council/United Kingdom -- WT106121MA/Wellcome Trust/United Kingdom -- England -- Nature. 2016 Mar 3;531(7592):64-9. doi: 10.1038/nature17199. Epub 2016 Feb 22.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Biomedical Research Centre, Norwich Medical School, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, UK. ; Diamond Light Source, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE, UK. ; Department of Biochemistry, University of Oxford, South Parks Road, Oxford OX1 3QU, UK. ; Jiangsu Province Key Laboratory of Anesthesiology, Xuzhou Medical College, Xuzhou 221004, China. ; Key Laboratory of Bio-resources and Eco-environment, Ministry of Education, Sichuan Key Laboratory of Molecular Biology and Biotechnology, College of Life Sciences, Sichuan University, Chengdu 610064, China. ; Laboratory of Department of Surgery, the First Affiliated Hospital, Sun Yat-sen University, 58 Zhongshan Road II, Guangzhou, Guangdong 510080, China.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/26901871" target="_blank"〉PubMed〈/a〉
    Keywords: Bacterial Outer Membrane Proteins/*chemistry/*metabolism ; Crystallography, X-Ray ; Escherichia coli/*chemistry ; Escherichia coli Proteins/*chemistry/*metabolism ; Lipoproteins/chemistry/metabolism ; Models, Molecular ; Molecular Dynamics Simulation ; Movement ; Multiprotein Complexes/*chemistry/*metabolism ; Periplasm/metabolism ; Protein Binding ; Protein Structure, Tertiary ; Protein Subunits/chemistry/metabolism ; Rotation
    Print ISSN: 0028-0836
    Electronic ISSN: 1476-4687
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    Electronic Resource
    Electronic Resource
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 30 (1992), S. 1383-1391 
    ISSN: 0887-624X
    Keywords: hydrophobic association ; associative polymers ; radical copolymerization ; polyacryl amides ; water-soluble polymers ; fluorine-containing polymers ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Fluorine-containing hydrophobically associating polymers have been synthesized by copolymerization of acrylamide with a small amount of an acrylate or methacrylate having a fluorocarbon containing ester group. It was found that hydrophobic associations occurring between these fluorocarbon chains was stronger than the interactions of the corresponding hydrocarbon comonomers and depend on the length of the fluorocarbon chain. The rheological properties of the copolymer solutions were studied. The solutions were found to be highly pseudoplastic but the viscosity loss was completely reversible upon removal of shear. Evidence for hydrophobic association of the fluorocarbon groups was obtained by the dependence of the Brookfield viscosity on temperature, the addition of NaCl, and the addition of organic solvents, urea, and surfactants.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    Publication Date: 2017-10-13
    Description: Halogens are among the most electronegative elements, and the variations in size and polarizability of halogens require different descriptions of the intermolecular bonds they form. Here we use the inelastic tunneling probe (itProbe) to acquire real-space imaging of intermolecular-bonding structures in the two-dimensional self-assembly of halogenbenzene molecules on a metal surface. Direct visualization is obtained for the intermolecular attraction and the "windmill" pattern of bonding among the fully halogenated molecules. Our results provide a hitherto missing understanding of the nature of the halogen bond.
    Keywords: Chemistry
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Geosciences , Computer Science , Medicine , Natural Sciences in General , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...