{"301241":{"#nid":"301241","#data":{"type":"news","title":"How Red Tide Knocks Out Its Competition","body":[{"value":"\u003Cp\u003ENew research reveals how the algae behind red tide thoroughly disables \u2013 but doesn\u2019t kill \u2013 other species of algae. The study shows how chemical signaling between algae can trigger big changes in the marine ecosystem.\u003C\/p\u003E\u003Cp\u003EMarine algae fight other species of algae for nutrients and light, and, ultimately, survival. The algae that cause red tides, the algal blooms that color blue ocean waters red, carry an arsenal of molecules that disable some other algae. The incapacitated algae don\u2019t necessarily die, but their growth grinds to a halt. This could explain part of why blooms can be maintained despite the presence of competitors. \u003C\/p\u003E\u003Cp\u003EIn the new study, scientists used cutting-edge tools in an attempt to solve an old ecological mystery: Why do some algae boom and some algae bust? The research team used cultured strains of the algae that cause red tide, exposed competitor algae to its exuded chemicals, and then took a molecular inventory of the competitor algae\u2019s growth and metabolism pathways. Red tide exposure significantly slowed the competitor algae\u2019s growth and compromised its ability to maintain healthy cell membranes. \u003C\/p\u003E\u003Cp\u003E\u201cOur study describes the physiological responses of competitors exposed to red tide compounds, and indicates why certain competitor species may be sensitive to these compounds while other species remain relatively resistant,\u201d said Kelsey Poulson-Ellestad, a former graduate student at the Georgia Institute of Technology, now at Woods Hole Oceanographic Institution, and the study\u2019s co-first author, along with Christina Jones, a Georgia Tech graduate student. \u201cThis can help us determine mechanisms that influence species composition in planktonic communities exposed to red tides, and suggests that these chemical cues could alter large-scale ecosystem phenomena, such as the funneling of material and energy through marine food webs.\u201d\u003C\/p\u003E\u003Cp\u003EThe study was sponsored by the National Science Foundation and was published June 2 in the \u003Ca href=\u0022http:\/\/www.pnas.org\/cgi\/doi\/10.1073\/pnas.1402130111%20\u0022\u003EOnline Early Edition of the journal \u003Cem\u003EProceedings of the National Academy of Sciences\u003C\/em\u003E\u003C\/a\u003E (PNAS). The work was a collaboration between Georgia Tech, the University of Washington, and the University of Birmingham in the United Kingdom.\u003C\/p\u003E\u003Cp\u003EThe algae that form red tide in the Gulf of Mexico are dinoflagellates called Karenia brevis, or just Karenia by scientists. Karenia makes neurotoxins that are toxic to humans and fish. Karenia also makes small molecules that are toxic to other marine algae, which is what the new study analyzed. \u003C\/p\u003E\u003Cp\u003E\u201cIn this study we employed a global look at the metabolism of these competitors to take an unbiased approach to ask how are they being affected by these non-lethal, subtle chemicals that are released by Karenia,\u201d said \u003Ca href=\u0022http:\/\/www.kubaneklab.biology.gatech.edu\/\u0022\u003EJulia Kubanek\u003C\/a\u003E, Poulson-Ellestad\u2019s graduate mentor and a professor in the School of Biology and the School of Chemistry and Biochemistry at Georgia Tech. \u201cBy studying both the proteins and metabolites, which interact to form metabolic pathways, we put together a picture of what\u2019s happening inside the competitor algal cells when they\u2019re extremely stressed.\u201d\u003C\/p\u003E\u003Cp\u003EThe research team used a combination of mass spectrometry and nuclear magnetic resonance spectroscopy to form a holistic picture of what\u2019s happening inside the competitor algae. The study is the first time that metabolites and proteins were measured simultaneously to study ecological competition.\u003C\/p\u003E\u003Cp\u003E\u0022A key aspect of this study was the use of high-resolution metabolomic tools based on mass spectrometry,\u0022 said \u003Ca href=\u0022http:\/\/ww2.chemistry.gatech.edu\/fernandez\/\u0022\u003EFacundo M. Fern\u00e1ndez\u003C\/a\u003E, a professor in the School of Chemistry and Biochemistry, whose lab ran the mass spectrometry analysis. \u0022This allowed us to detect and identify metabolites affected by exposure to red tide microorganisms.\u201d \u003C\/p\u003E\u003Cp\u003EMass spectrometry was also used for analysis of proteins, an approach called proteomics, led by Brook Nunn at the University of Washington.\u003C\/p\u003E\u003Cp\u003EThe research team discovered that red tide disrupts multiple physiological pathways in the competitor diatom Thalassiosira pseudonana. Red tide disrupted the energy metabolism and cellular protection mechanisms, inhibited their ability to regulate fluids and increased oxidative stress. T. pseudonana exposed to red tide toxins grew 85 percent slower than unexposed algae.\u003C\/p\u003E\u003Cp\u003E\u201cThis competitor that\u2019s being affected by red tide is suffering a globally upset state,\u201d Kubanek said. \u201cIt\u2019s nothing like what it would be in a healthy, normal cell.\u201d\u003C\/p\u003E\u003Cp\u003EThe work shows that chemical cues in the plankton have the potential to alter large-scale ecosystem processes including primary production and nutrient cycling in the ocean. \u003C\/p\u003E\u003Cp\u003EThe research team found that another competitor diatom, Asterionellopsis glacialis, which frequently co-occurs with Karenia red tides, was partially resistant to red tide, suggesting that co-occurring species may have evolved partial resistance to red tide via robust metabolic pathways. \u003C\/p\u003E\u003Cp\u003EOther work in Kubanek\u2019s lab is examining red tide and its competition in the field to see how these interactions unfold in the wild.\u003C\/p\u003E\u003Cp\u003E\u201cKarenia is a big mystery. It has these periodic blooms that happen most years now, but what\u2019s shaping that cycle is unclear,\u201d Kubanek said. \u201cThe role of competitive chemical cues in these interactions is also not well understood.\u201d \u003C\/p\u003E\u003Cp\u003E\u003Cem\u003EThis research is supported by the National Science Foundation under award number OCE-1060300. Any conclusions or opinions are those of the authors and do not necessarily represent the official views of the sponsoring agency.\u003C\/em\u003E\u003C\/p\u003E\u003Cp\u003E\u003Cstrong\u003ECITATION\u003C\/strong\u003E: Kelsey L. Poulson-Ellestad, et al., \u201cMetabolomics and proteomics reveal impacts of chemically mediated competition on marine plankton.\u201d (June, \u003Cem\u003EPNAS\u003C\/em\u003E) \u003Ca href=\u0022http:\/\/www.pnas.org\/cgi\/doi\/10.1073\/pnas.1402130111%20\u0022\u003Ewww.pnas.org\/cgi\/doi\/10.1073\/pnas.1402130111 \u003C\/a\u003E\u003C\/p\u003E\u003Cp\u003E\u003Cstrong\u003EResearch News\u003C\/strong\u003E\u003Cbr \/\u003E\u003Cstrong\u003EGeorgia Institute of Technology\u003C\/strong\u003E\u003Cbr \/\u003E\u003Cstrong\u003E177 North Avenue\u003C\/strong\u003E\u003Cbr \/\u003E\u003Cstrong\u003EAtlanta, Georgia 30332-0181 USA\u003C\/strong\u003E\u003Cbr \/\u003E\u003Ca href=\u0022https:\/\/twitter.com\/gtresearchnews\u0022\u003E\u003Cstrong\u003E@GTResearchNews\u003C\/strong\u003E\u003C\/a\u003E\u003C\/p\u003E\u003Cp\u003E\u003Cstrong\u003EMedia Relations Contacts:\u003C\/strong\u003E Brett Israel (\u003Ca href=\u0022https:\/\/twitter.com\/btiatl\u0022\u003E@btiatl\u003C\/a\u003E) (404-385-1933) (\u003Ca href=\u0022mailto:brett.israel@comm.gatech.edu\u0022\u003Ebrett.israel@comm.gatech.edu\u003C\/a\u003E) or John Toon (404-894-6986) (\u003Ca href=\u0022mailto:jtoon@gatech.edu\u0022\u003Ejtoon@gatech.edu\u003C\/a\u003E)\u003C\/p\u003E\u003Cp\u003E\u003Cstrong\u003EWriter\u003C\/strong\u003E: Brett Israel\u003C\/p\u003E","summary":null,"format":"limited_html"}],"field_subtitle":"","field_summary":[{"value":"\u003Cp\u003ENew research reveals how the algae behind red tide thoroughly disables \u2013 but doesn\u2019t kill \u2013 other species of algae. The study shows how chemical signaling between algae can trigger big changes in the marine ecosystem.\u003C\/p\u003E","format":"limited_html"}],"field_summary_sentence":[{"value":"New research reveals how the algae behind red tide thoroughly disables \u2013 but doesn\u2019t kill \u2013 other species of algae."}],"uid":"27902","created_gmt":"2014-06-04 11:15:07","changed_gmt":"2016-10-08 03:16:33","author":"Brett Israel","boilerplate_text":"","field_publication":"","field_article_url":"","dateline":{"date":"2014-06-04T00:00:00-04:00","iso_date":"2014-06-04T00:00:00-04:00","tz":"America\/New_York"},"extras":[],"hg_media":{"301231":{"id":"301231","type":"image","title":"Red tide sampling","body":null,"created":"1449244572","gmt_created":"2015-12-04 15:56:12","changed":"1475895004","gmt_changed":"2016-10-08 02:50:04","alt":"Red tide sampling","file":{"fid":"199547","name":"kelseyfield.jpg","image_path":"\/sites\/default\/files\/images\/kelseyfield_0.jpg","image_full_path":"http:\/\/www.tlwarc.hg.gatech.edu\/\/sites\/default\/files\/images\/kelseyfield_0.jpg","mime":"image\/jpeg","size":2588234,"path_740":"http:\/\/www.tlwarc.hg.gatech.edu\/sites\/default\/files\/styles\/740xx_scale\/public\/images\/kelseyfield_0.jpg?itok=AaSHTfEQ"}},"301221":{"id":"301221","type":"image","title":"Red tide","body":null,"created":"1449244572","gmt_created":"2015-12-04 15:56:12","changed":"1475895004","gmt_changed":"2016-10-08 02:50:04","alt":"Red tide","file":{"fid":"199546","name":"kbrevisbloom.jpg","image_path":"\/sites\/default\/files\/images\/kbrevisbloom_0.jpg","image_full_path":"http:\/\/www.tlwarc.hg.gatech.edu\/\/sites\/default\/files\/images\/kbrevisbloom_0.jpg","mime":"image\/jpeg","size":514284,"path_740":"http:\/\/www.tlwarc.hg.gatech.edu\/sites\/default\/files\/styles\/740xx_scale\/public\/images\/kbrevisbloom_0.jpg?itok=UUIuseXN"}}},"media_ids":["301231","301221"],"groups":[{"id":"1188","name":"Research Horizons"}],"categories":[{"id":"154","name":"Environment"},{"id":"146","name":"Life Sciences and Biology"}],"keywords":[{"id":"17301","name":"Facundo Fernandez"},{"id":"4647","name":"Julia Kubanek"},{"id":"75851","name":"Karenia brevis"},{"id":"94651","name":"red tide"}],"core_research_areas":[{"id":"39441","name":"Bioengineering and Bioscience"}],"news_room_topics":[{"id":"71911","name":"Earth and Environment"}],"event_categories":[],"invited_audience":[],"affiliations":[],"classification":[],"areas_of_expertise":[],"news_and_recent_appearances":[],"phone":[],"contact":[{"value":"\u003Cp\u003EBrett Israel\u003C\/p\u003E\u003Cp\u003E404-385-1933\u003C\/p\u003E\u003Cp\u003E\u003Ca href=\u0022mailto:brett.israel@comm.gatech.edu\u0022\u003Ebrett.israel@comm.gatech.edu\u003C\/a\u003E\u003C\/p\u003E\u003Cp\u003E\u003Ca href=\u0022https:\/\/twitter.com\/btiatl\u0022\u003E@btiatl\u003C\/a\u003E\u003C\/p\u003E","format":"limited_html"}],"email":["brett.israel@comm.gatech.edu"],"slides":[],"orientation":[],"userdata":""}}}