{"512211":{"#nid":"512211","#data":{"type":"event","title":"Bacterial Outer Membranes and Interactions with Membrane Proteins","body":[{"value":"\u003Cp\u003EThe outer membrane of gram-negative bacteria is a unique asymmetric membrane bilayer that is composed of phospholipids in the inner leaflet and lipopolysaccharides (LPS) in the outer leaflet. Its function as a selective barrier is crucial for the survival of bacteria in many distinct environments, and it also renders gram-negative bacteria more resistant to antibiotics than their gram-positive counterparts. LPS comprises three regions: lipid A, core oligosaccharide, and O-antigen polysaccharide. In this talk, I will present our ongoing efforts on understanding various bacterial outer membranes and their interactions with outer membrane proteins, including (1) construction of\u0026nbsp;a model of an \u003Cem\u003EE. coli\u003C\/em\u003E R1 (core) O6 (antigen) LPS molecule using\u0026nbsp;the CHARMM36 lipid and carbohydrate force fields and simulations of various \u003Cem\u003EE. coli\u003C\/em\u003E R1.O6 LPS bilayers; (2) modeling of \u003Cem\u003EE. coli\u003C\/em\u003E R2, R3, R4, and K12 cores and other O-antigens and their bilayer simulations; (3) development of LPS Modeler in CHARMM-GUI; (4) modeling and simulation of \u003Cem\u003EE. coli\u003C\/em\u003E outer membranes with\u0026nbsp;phospholipids in the inner leaflet and LPS in the outer leaflet as well as OmpLA in the outer membrane; (5) modeling and simulation of BamA in the \u003Cem\u003EE. coli \u003C\/em\u003Eouter membrane; (6) other ongoing outer membrane - protein simulations.\u003C\/p\u003E\u003Cp\u003E\u003Cstrong\u003EGram-negative bacterial outer membrane molecular complexity. \u003C\/strong\u003EThis image illustrates a typical \u003Cem\u003EE. coli\u003C\/em\u003E outer membrane. The bilayer is composed of (from the top, external leaflet) glycosylated amphipathic molecules known as lipopolysaccharide (LPS) consisting of an O-antigen polysaccharide, a core oligosaccharide, and lipid A and (the bottom, periplasmic leaflet) consisting of various phospholipid molecules. The cyan atoms interspersed with the core oligosaccharides are calcium atoms, which immobilize the membrane by mediating the cross-linking electrostatic interaction network. K\u003Csup\u003E+\u003C\/sup\u003E and Cl\u003Csup\u003E-\u003C\/sup\u003E ions are magenta and green spheres.\u003C\/p\u003E","summary":null,"format":"limited_html"}],"field_subtitle":"","field_summary":"","field_summary_sentence":[{"value":"Bacterial Outer Membranes and Interactions with Membrane Proteins"}],"uid":"30957","created_gmt":"2016-03-11 10:51:05","changed_gmt":"2017-04-13 21:16:20","author":"Shaun Ashley","boilerplate_text":"","field_publication":"","field_article_url":"","field_event_time":{"event_time_start":"2016-04-12T16:00:00-04:00","event_time_end":"2016-04-12T17:00:00-04:00","event_time_end_last":"2016-04-12T17:00:00-04:00","gmt_time_start":"2016-04-12 20:00:00","gmt_time_end":"2016-04-12 21:00:00","gmt_time_end_last":"2016-04-12 21:00:00","rrule":null,"timezone":"America\/New_York"},"extras":[],"hg_media":{"512241":{"id":"512241","type":"image","title":"Wonpil Im Image","body":null,"created":"1458923712","gmt_created":"2016-03-25 16:35:12","changed":"1475895275","gmt_changed":"2016-10-08 02:54:35","alt":"Wonpil Im Image","file":{"fid":"205008","name":"wonpil_pic.png","image_path":"\/sites\/default\/files\/images\/wonpil_pic_0.png","image_full_path":"http:\/\/www.tlwarc.hg.gatech.edu\/\/sites\/default\/files\/images\/wonpil_pic_0.png","mime":"image\/png","size":1015898,"path_740":"http:\/\/www.tlwarc.hg.gatech.edu\/sites\/default\/files\/styles\/740xx_scale\/public\/images\/wonpil_pic_0.png?itok=YN7C4VAX"}}},"media_ids":["512241"],"groups":[{"id":"126011","name":"School of Physics"}],"categories":[],"keywords":[{"id":"166937","name":"School of Physics"},{"id":"166896","name":"seminar"}],"core_research_areas":[],"news_room_topics":[],"event_categories":[{"id":"1795","name":"Seminar\/Lecture\/Colloquium"}],"invited_audience":[{"id":"78751","name":"Undergraduate students"},{"id":"78761","name":"Faculty\/Staff"},{"id":"174045","name":"Graduate students"}],"affiliations":[],"classification":[],"areas_of_expertise":[],"news_and_recent_appearances":[],"phone":[],"contact":[{"value":"\u003Cp\u003E\u003Ca href=\u0022mailto:shaun.ashley@physics.gatech.edu\u0022\u003Eshaun.ashley@physics.gatech.edu\u003C\/a\u003E\u003C\/p\u003E","format":"limited_html"}],"email":[],"slides":[],"orientation":[],"userdata":""}}}