KUKU

KU ScholarWorks

  • myKU
  • Email
  • Enroll & Pay
  • KU Directory
    • Login
    View Item 
    •   KU ScholarWorks
    • Molecular Biosciences
    • Molecular Biosciences Scholarly Works
    • View Item
    •   KU ScholarWorks
    • Molecular Biosciences
    • Molecular Biosciences Scholarly Works
    • View Item
    JavaScript is disabled for your browser. Some features of this site may not work without it.

    Membrane Tension, Lipid Adaptation, Conformational Changes, and Energetics in MscL Gating

    Thumbnail
    View/Open
    Wonpil_v101_p671-679.pdf (810.9Kb)
    Issue Date
    2011-08-03
    Author
    Rui, Huan
    Kumar, Ritesh
    Im, Wonpil
    Publisher
    Elsevier
    Type
    Article
    Article Version
    Scholarly/refereed, publisher version
    Metadata
    Show full item record
    Abstract
    This study aims to explore gating mechanisms of mechanosensitive channels in terms of membrane tension, membrane adaptation, protein conformation, and energetics. The large conductance mechanosensitive channel from Mycobacterium tuberculosis (Tb-MscL) is used as a model system; Tb-MscL acts as a safety valve by releasing small osmolytes through the channel opening under extreme hypoosmotic conditions. Based on the assumption that the channel gating involves tilting of the transmembrane (TM) helices, we have performed free energy simulations of Tb-MscL as a function of TM helix tilt angle in a dimyristoylphosphatidylcholine bilayer. Based on the change in system dimensions, TM helix tilting is shown to be essentially equivalent to applying an excess surface tension to the membrane, causing channel expansion, lipid adaptation, and membrane thinning. Such equivalence is further corroborated by the observation that the free energy cost of Tb-MscL channel expansion is comparable to the work done by the excess surface tension. Tb-MscL TM helix tilting results in an expanded water-conducting channel of an outer dimension similar to the proposed fully open MscL structure. The free energy decomposition indicates a possible expansion mechanism in which tilting and expanding of TM2 facilitates the iris-like motion of TM1, producing an expanded Tb-MscL.
    Description
    This is the publisher's version. Copyright 2011 by Elsevier.
    URI
    http://hdl.handle.net/1808/17477
    DOI
    https://doi.org/10.1016/j.bpj.2011.06.029
    Collections
    • Molecular Biosciences Scholarly Works [598]
    Citation
    Rui, Huan, Ritesh Kumar, and Wonpil Im. "Membrane Tension, Lipid Adaptation, Conformational Changes, and Energetics in MscL Gating." Biophysical Journal 101.3 (2011): 671-79. http://dx.doi.org/10.1016/j.bpj.2011.06.029.

    Items in KU ScholarWorks are protected by copyright, with all rights reserved, unless otherwise indicated.


    We want to hear from you! Please share your stories about how Open Access to this item benefits YOU.


    Contact KU ScholarWorks
    785-864-8983
    KU Libraries
    1425 Jayhawk Blvd
    Lawrence, KS 66045
    785-864-8983

    KU Libraries
    1425 Jayhawk Blvd
    Lawrence, KS 66045
    Image Credits
     

     

    Browse

    All of KU ScholarWorksCommunities & CollectionsThis Collection

    My Account

    Login

    Statistics

    View Usage Statistics

    Contact KU ScholarWorks
    785-864-8983
    KU Libraries
    1425 Jayhawk Blvd
    Lawrence, KS 66045
    785-864-8983

    KU Libraries
    1425 Jayhawk Blvd
    Lawrence, KS 66045
    Image Credits
     

     

    The University of Kansas
      Contact KU ScholarWorks
    Lawrence, KS | Maps
     
    • Academics
    • Admission
    • Alumni
    • Athletics
    • Campuses
    • Giving
    • Jobs

    The University of Kansas prohibits discrimination on the basis of race, color, ethnicity, religion, sex, national origin, age, ancestry, disability, status as a veteran, sexual orientation, marital status, parental status, gender identity, gender expression and genetic information in the University’s programs and activities. The following person has been designated to handle inquiries regarding the non-discrimination policies: Director of the Office of Institutional Opportunity and Access, IOA@ku.edu, 1246 W. Campus Road, Room 153A, Lawrence, KS, 66045, (785)864-6414, 711 TTY.

     Contact KU
    Lawrence, KS | Maps