Oligomeric Structure of Colicin Ia Channel in Lipid Bilayer Membranes Export

@article{citeulike:4782450, abstract = {Colicin Ia is a soluble, harpoon-shaped bacteriocin which translocates across the periplasmic space of sensitive Escherichia coli cell by parasitizing an outer membrane receptor and forms voltage-gated ion channels in the inner membrane. This process leads to cell death, which has been thought to be caused by a single colicin Ia molecule. To directly visualize the three-dimensional structure of the channel, we generated two-dimensional crystals of colicin Ia inserted in lipid-bilayer membranes and determined a [\~{}]17 three-dimensional model by electron crystallography. Supported by velocity sedimentation, chemical cross-linking and single-particle image analysis, the three-dimensional structure is a crown-shaped oligomer enclosing a [\~{}]35 A-wide extrabilayer vestibule. Our study suggests that lipid insertion instigates a global conformational change in colicin Ia and that more than one molecule participates in the channel architecture with the vestibule, possibly facilitating the known large scale peptide translocation upon channel opening. 10.1074/jbc.M900292200}, author = {Greig, Sarah L. and Radjainia, Mazdak and Mitra, Alok K.}, citeulike-article-id = {4782450}, citeulike-linkout-0 = {http://dx.doi.org/10.1074/jbc.M900292200}, citeulike-linkout-1 = {http://www.jbc.org/cgi/content/abstract/284/24/16126?rss=1}, citeulike-linkout-2 = {http://view.ncbi.nlm.nih.gov/pubmed/19357078}, citeulike-linkout-3 = {http://www.hubmed.org/display.cgi?uids=19357078}, day = {12}, doi = {10.1074/jbc.M900292200}, journal = {J. Biol. Chem.}, keywords = {1a, bilayer, channel, colicin, greig09pdf, lipid, membranes, stoichiometry}, month = {June}, number = {24}, pages = {16126--16134}, posted-at = {2009-06-09 00:41:12}, priority = {2}, title = {Oligomeric Structure of Colicin Ia Channel in Lipid Bilayer Membranes}, url = {http://dx.doi.org/10.1074/jbc.M900292200}, volume = {284}, year = {2009} }

TY - JOUR ID - citeulike:4782450 L3 - citeulike-article-id:4782450 N2 - Colicin Ia is a soluble, harpoon-shaped bacteriocin which translocates across the periplasmic space of sensitive Escherichia coli cell by parasitizing an outer membrane receptor and forms voltage-gated ion channels in the inner membrane. This process leads to cell death, which has been thought to be caused by a single colicin Ia molecule. To directly visualize the three-dimensional structure of the channel, we generated two-dimensional crystals of colicin Ia inserted in lipid-bilayer membranes and determined a [~]17 three-dimensional model by electron crystallography. Supported by velocity sedimentation, chemical cross-linking and single-particle image analysis, the three-dimensional structure is a crown-shaped oligomer enclosing a [~]35 A-wide extrabilayer vestibule. Our study suggests that lipid insertion instigates a global conformational change in colicin Ia and that more than one molecule participates in the channel architecture with the vestibule, possibly facilitating the known large scale peptide translocation upon channel opening. 10.1074/jbc.M900292200 IS - 24 JF - J. Biol. Chem. EP - 16134 TI - Oligomeric Structure of Colicin Ia Channel in Lipid Bilayer Membranes VL - 284 SP - 16126 KW - 1a KW - bilayer KW - channel KW - colicin KW - greig09pdf KW - lipid KW - membranes KW - stoichiometry AU - Greig, Sarah AU - Radjainia, Mazdak AU - Mitra, Alok PY - 2009/06/12/ UR - http://dx.doi.org/10.1074/jbc.M900292200 ER -