{"73806":{"#nid":"73806","#data":{"type":"news","title":"Researchers Uncover E.coli\u0027s Defense Mechanism","body":[{"value":"\u003Cp\u003EResearchers at the Georgia Institute of Technology and the John Innes Centre in the United Kingdom have uncovered a mechanism with which disease-causing bacteria may thwart the body\u0027s natural defense responses. The findings, which could ultimately lead to the development of more effective antibiotics, appear in the September 29, 2005 issue of the journal Nature.\u003C\/p\u003E\n\u003Cp\u003E\u0022Nitric oxide is produced by the body to fight infections. We discovered a mechanism that allows bacterial cells to detect nitric oxide and turn it into something that\u0027s harmless to the cell,\u0022 said Stephen Spiro, associate professor in the School of Biology at Georgia Tech.\n\u003C\/p\u003E\n\u003Cp\u003ESpiro, along with colleagues Beno\u00eet D\u0027Autr\u00e9auz, Nicholas Tucker and Ray Dixon from the John Innes Centre, studied a non-pathogenic strain of Escherichia coli, which is very closely related to salmonella bacteria.\n\u003C\/p\u003E\n\u003Cp\u003EThe pathogenic forms of E. coli and salmonella are usually transmitted to humans through undercooked meat, unwashed vegetables and cross contamination from surfaces on which these foods were prepared. Infections from either of these organisms can cause diarrhea, abdominal cramps and sometimes more serious illnesses that require hospitalization. E.coli doesn\u0027t respond well to antibiotics, while salmonella has developed several drug-resistant strains. Learning how the bacteria handle the body\u0027s immune response is the first step in developing more effective medicines.\n\u003C\/p\u003E\n\u003Cp\u003ESpiro and colleagues focused their study on the NorR protein and the role it plays in reducing the levels of nitric oxide. In response to nitric oxide, NorR binds to DNA in order to regulate expression of an enzyme that reduces the amount of nitric oxide in the bacteria. Since nitric oxide binds to metals, the researchers suspected that there might be a metal in the protein.\n\u003C\/p\u003E\n\u003Cp\u003E\u0022It turns out that the protein NorR contains a single molecule of iron,\u0022 said Spiro. \u0022Our study found that the nitric oxide binds to the iron, which in turn activates the protein.\u0022\n\u003C\/p\u003E\n\u003Cp\u003EOnce activated, the protein controls expression of the norVW genes. These genes encode an enzyme that removes the nitric oxide, allowing the bacteria to fend off the body\u0027s defenses.\n\u003C\/p\u003E\n\u003Cp\u003EThe discovery of this mechanism is just the first step in what Spiro hopes will be a line of research aimed at disrupting the mechanism by which the bacteria rids itself of the poisonous nitric oxide.\n\u003C\/p\u003E\n\u003Cp\u003E\u0022If we can interfere with the mechanism, it could lead to better antibiotics and better treatments,\u0022 said Spiro.\n\u003C\/p\u003E\n\u003Cp\u003EThe research was funded by a grant from the Biotechnology and Biological Sciences Research Council.\n\u003C\/p\u003E","summary":null,"format":"limited_html"}],"field_subtitle":"","field_summary":[{"value":"Researchers have uncovered a mechanism with which disease-causing bacteria may thwart the body\u0027s natural defense responses. The findings could ultimately lead to the development of more effective antibiotics.","format":"limited_html"}],"field_summary_sentence":[{"value":"Iron key to nitric oxide reduction"}],"uid":"27310","created_gmt":"2005-09-28 00:00:00","changed_gmt":"2016-10-08 03:00:59","author":"David Terraso","boilerplate_text":"","field_publication":"","field_article_url":"","dateline":{"date":"2005-09-28T00:00:00-04:00","iso_date":"2005-09-28T00:00:00-04:00","tz":"America\/New_York"},"extras":[],"hg_media":{"73807":{"id":"73807","type":"image","title":"Escherichia coli O157:H7","body":null,"created":"1449178020","gmt_created":"2015-12-03 21:27:00","changed":"1475894678","gmt_changed":"2016-10-08 02:44:38"}},"media_ids":["73807"],"groups":[{"id":"1214","name":"News Room"}],"categories":[],"keywords":[],"core_research_areas":[],"news_room_topics":[],"event_categories":[],"invited_audience":[],"affiliations":[],"classification":[],"areas_of_expertise":[],"news_and_recent_appearances":[],"phone":[],"contact":[{"value":"\u003Cp\u003E\u003Cstrong\u003EGeorgia Tech Media Relations\u003C\/strong\u003E\u003Cbr \/\u003ELaura Diamond\u003Cbr \/\u003E\u003Ca href=\u0022mailto:laura.diamond@comm.gatech.edu\u0022\u003Elaura.diamond@comm.gatech.edu\u003C\/a\u003E\u003Cbr \/\u003E404-894-6016\u003Cbr \/\u003EJason Maderer\u003Cbr \/\u003E\u003Ca href=\u0022mailto:maderer@gatech.edu\u0022\u003Emaderer@gatech.edu\u003C\/a\u003E\u003Cbr \/\u003E404-660-2926\u003C\/p\u003E","format":"limited_html"}],"email":["david.terraso@comm.gatech.edu"],"slides":[],"orientation":[],"userdata":""}}}