{"635580":{"#nid":"635580","#data":{"type":"news","title":"Cavity-causing Bacteria Assemble an Army of Protective Microbes on Human Teeth ","body":[{"value":"\u003Cp\u003E\u003Cem\u003E\u003Cstrong\u003E\u003Ca href=\u0022http:\/\/penntoday.upenn.edu\/news\/cavity-causing-bacteria-assemble-army-protective-microbes-human-teeth\u0022 target=\u0022_blank\u0022\u003EStory\u003C\/a\u003E\u003Ca href=\u0022http:\/\/penntoday.upenn.edu\/news\/cavity-causing-bacteria-assemble-army-protective-microbes-human-teeth\u0022 target=\u0022_blank\u0022\u003E by Katherine Unger Baillie, Science News Officer, University of Pennsylvania\u003C\/a\u003E\u003C\/strong\u003E\u003C\/em\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003EStudying bacteria in a petri dish or test tube has yielded insights into how they function and, in some cases, contribute to disease. But this approach leaves out crucial details about how bacteria act in the real world.\u003C\/p\u003E\r\n\r\n\u003Cp\u003ETaking a translational approach, researchers at the \u003Ca href=\u0022https:\/\/www.upe\u0022\u003EUniversity of Pennsylvania\u003C\/a\u003E \u003Ca href=\u0022https:\/\/www.dental.upenn.edu\/\u0022\u003ESchool of Dental Medicine\u003C\/a\u003E and the \u003Ca href=\u0022https:\/\/www.gatech.edu\/\u0022\u003EGeorgia Institute of Technology\u003C\/a\u003E imaged the bacteria that cause tooth decay in three dimensions in their natural environment, the sticky biofilm known as dental plaque formed on toddlers\u2019 teeth that were affected by cavities.\u003C\/p\u003E\r\n\r\n\u003Cp\u003EThe work, published in the journal \u003Ca href=\u0022https:\/\/doi.org\/10.1073\/pnas.1919099117\u0022\u003E\u003Cem\u003EProceedings of the National Academy of Sciences\u003C\/em\u003E\u003C\/a\u003E, found that \u003Cem\u003EStreptococcus mutans\u003C\/em\u003E, a major bacterial species responsible for tooth decay, is encased in a protective multilayered community of other bacteria and polymers forming a unique spatial organization associated with the location of the disease onset.\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u201cWe started with these clinical samples, extracted teeth from children with severe tooth decay,\u201d says \u003Ca href=\u0022https:\/\/www.dental.upenn.edu\/faculty\/hyun-michel-koo\/\u0022\u003EHyun (Michel) Koo\u003C\/a\u003E of Penn Dental Medicine, a co-senior author on the work. \u201cThe question that popped in our minds was, how these bacteria are organized and whether their specific architecture can tell us about the disease they cause?\u201d\u003C\/p\u003E\r\n\r\n\u003Cp\u003ETo address this question, the researchers, including lead author \u003Ca href=\u0022https:\/\/www.dental.upenn\u0022\u003EDongyeop Kim\u003C\/a\u003E of Penn Dental Medicine and co-senior author \u003Ca href=\u0022https:\/\/biosciences.gatech.edu\/people\/marvin-whiteley\u0022\u003EMarvin Whiteley\u003C\/a\u003E of Georgia Tech, used a combination of super-resolution confocal and scanning electron microscopy with computational analysis to dissect the arrangement of \u003Cem\u003ES. mutans\u003C\/em\u003E and other microbes of the intact biofilm on the teeth. These techniques allowed the team to examine the biofilm layer by layer, gaining a three-dimensional picture of the specific architectures.\u003C\/p\u003E\r\n\r\n\u003Cp\u003EThis approach, of understanding the locations and patterns of bacteria, is one that Whiteley has pursued in other diseases.\u0026nbsp;\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u201cIt\u2019s clear that identifying the constituents of the human microbiome is not enough to understand their impact on human health,\u201d Whiteley says. \u201cWe also have to know how they are spatially organized. This is largely under studied as obtaining intact samples that maintain spatial structure is difficult.\u201d \u0026nbsp;\u003C\/p\u003E\r\n\r\n\u003Cp\u003EIn the current work, the researchers discovered that \u003Cem\u003ES. mutans \u003C\/em\u003Ein dental plaque most often appeared in a particular fashion: arranged in a mound against the tooth\u2019s surface. But it wasn\u2019t alone. While \u003Cem\u003ES. mutans\u003C\/em\u003E formed the inner core of the rotund architecture, other commensal bacteria, such as \u003Cem\u003ES. oralis\u003C\/em\u003E, formed additional outer layers precisely arranged in a crownlike structure. Supporting and separating these layers was an extracellular scaffold made of sugars produced by \u003Cem\u003ES. mutans\u003C\/em\u003E, effectively encasing and protecting the disease-causing bacteria.\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u201cWe found this highly ordered community with a dense accumulation of \u003Cem\u003ES. mutans \u003C\/em\u003Ein the middle\u003Cem\u003E \u003C\/em\u003Esurrounded by these \u2018halos\u2019 of different bacteria, and wondered how this could cause tooth decay,\u201d Koo says. \u201c\u003C\/p\u003E\r\n\r\n\u003Cp\u003ETo learn more about how structure impacted the function of the biofilm, the research team attempted to recreate the natural plaque formations on a toothlike surface in the lab using \u003Cem\u003ES. mutans\u003C\/em\u003E, \u003Cem\u003ES. oralis\u003C\/em\u003E, and a sugar solution. They successfully grew the formations, with rotund-shaped architecture and crown-like structure, and then measured levels of acid and demineralization associated with them.\u0026nbsp;\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u201cWhat we discovered, and what was exciting for us, is that the rotund areas perfectly matched with the demineralized and high acid levels on the enamel surface,\u201d says Koo. \u201cThis mirrors what clinicians see when they find dental caries: punctuated areas of decalcification known as \u2018white spots.\u2019 The crown-like structure could explain how cavities get their start.\u201d\u0026nbsp;\u003C\/p\u003E\r\n\r\n\u003Cp\u003EIn a final set of experiments, the team put the community to the test, applying an antimicrobial treatment and observing how the bacteria fared. When the crown-like structures were intact, the \u003Cem\u003ES. mutans\u003C\/em\u003E in the inner core largely avoided dying from the antimicrobial treatment. Only breaking up the scaffolding material holding the outer layers together enabled the antimicrobial to penetrate and effectively kill the cavity-causing bacteria.\u003C\/p\u003E\r\n\r\n\u003Cp\u003EThe study\u2019s findings may help researcher more effectively target the pathogenic core of dental biofilms but also have implications for other fields.\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u201cIt demonstrates that the spatial structure of the microbiome may mediate function and the disease outcome, which could be applicable to other medical fields dealing with polymicrobial infections,\u201d says Koo.\u0026nbsp;\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u201cIt\u2019s not just which pathogens are there but how they\u2019re structured that tells you about the disease that they cause,\u201d adds Whiteley. \u201cBacteria are highly social creatures and have friends and enemies that dictate their behaviors.\u201d\u0026nbsp;\u003C\/p\u003E\r\n\r\n\u003Cp\u003EThe field of microbial biogeography is young, the researchers say, but extending this demonstration that links community structure with disease onset opens up a vast array of possibilities for future medically relevant insights.\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u0026nbsp;\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cem\u003EDongyeop Kim was a research associate at Penn\u2019s School of Dental Medicine\u2019s Department of Orthodontics and is now an assistant professor at the Jeonbuk National University (Korea).\u003C\/em\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cem\u003EHyun (Michel) Koo is a professor in Penn\u2019s School of Dental Medicine\u2019s Department of Orthodontics in the divisions of Community Oral Health and Pediatric Dentistry.\u003C\/em\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cem\u003EMarvin Whiteley is a professor of biological sciences, the Georgia Tech Bennie H. and Nelson D. Abell Chair in Molecular and Cellular Biology, and the Georgia Research Alliance Eminent Scholar co-director in Emory-Children\u2019s CF Center at the Georgia Institute of Technology.\u003C\/em\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cem\u003EKoo, Kim, and Whiteley\u2019s coauthors were Penn Dental Medicine\u2019s Rodrigo A. Arthur, Yuan Liu, Elizabeth L. Scisci, and Evlambia Hajishengallis; Georgia Tech\u2019s Juan P. Barraza; and Indiana University\u2019s Anderson Hara and Karl Lewis.\u003C\/em\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cem\u003EThe work was supported in part by the National Institute for Dental and Craniofacial Research (grants DE025220, DE018023, DE020100, and DE023193).\u003C\/em\u003E\u003C\/p\u003E\r\n","summary":"","format":"limited_html"}],"field_subtitle":"","field_summary":[{"value":"\u003Cp\u003EExamining bacteria growing on toddlers\u2019 teeth, Marvin Whiteley and a team from the University of Pennsylvania found microbes\u2019 spatial organization is crucial to how they cause tooth decay.\u003C\/p\u003E\r\n","format":"limited_html"}],"field_summary_sentence":[{"value":"Examining bacteria growing on toddlers\u2019 teeth, Marvin Whiteley and a team from the University of Pennsylvania found microbes\u2019 spatial organization is crucial to how they cause tooth decay."}],"uid":"34528","created_gmt":"2020-05-22 00:07:59","changed_gmt":"2024-02-15 20:21:18","author":"jhunt7","boilerplate_text":"","field_publication":"","field_article_url":"","dateline":{"date":"2020-05-21T00:00:00-04:00","iso_date":"2020-05-21T00:00:00-04:00","tz":"America\/New_York"},"extras":[],"hg_media":{"635577":{"id":"635577","type":"image","title":"With powerful microscopy, researchers were able to visualize the structure of a tooth decay-causing biofilm growing on toddlers\u2019 teeth. The organism primarily responsible for cavities, Streptococcus mutans, labeled in green, shields itself under layers of","body":null,"created":"1590104051","gmt_created":"2020-05-21 23:34:11","changed":"1590104051","gmt_changed":"2020-05-21 23:34:11","alt":"","file":{"fid":"241862","name":"Image by Dongyeop Kim.jpg","image_path":"\/sites\/default\/files\/images\/Image%20by%20Dongyeop%20Kim.jpg","image_full_path":"http:\/\/hg.gatech.edu\/\/sites\/default\/files\/images\/Image%20by%20Dongyeop%20Kim.jpg","mime":"image\/jpeg","size":593173,"path_740":"http:\/\/hg.gatech.edu\/sites\/default\/files\/styles\/740xx_scale\/public\/images\/Image%20by%20Dongyeop%20Kim.jpg?itok=0o6JrgZF"}},"635579":{"id":"635579","type":"image","title":"Marvin Whiteley of Georgia Tech, a co-senior author on the work.","body":null,"created":"1590104378","gmt_created":"2020-05-21 23:39:38","changed":"1590104378","gmt_changed":"2020-05-21 23:39:38","alt":"","file":{"fid":"241864","name":"EminentScholar_Whiteley.jpg","image_path":"\/sites\/default\/files\/images\/EminentScholar_Whiteley.jpg","image_full_path":"http:\/\/hg.gatech.edu\/\/sites\/default\/files\/images\/EminentScholar_Whiteley.jpg","mime":"image\/jpeg","size":50343,"path_740":"http:\/\/hg.gatech.edu\/sites\/default\/files\/styles\/740xx_scale\/public\/images\/EminentScholar_Whiteley.jpg?itok=Jji4XKHs"}},"635578":{"id":"635578","type":"image","title":"Hyun (Michel) Koo of Penn Dental Medicine, a co-senior author on the work.","body":null,"created":"1590104276","gmt_created":"2020-05-21 23:37:56","changed":"1590104276","gmt_changed":"2020-05-21 23:37:56","alt":"","file":{"fid":"241863","name":"Hyun (Michel) Koo.JPG","image_path":"\/sites\/default\/files\/images\/Hyun%20%28Michel%29%20Koo.JPG","image_full_path":"http:\/\/hg.gatech.edu\/\/sites\/default\/files\/images\/Hyun%20%28Michel%29%20Koo.JPG","mime":"image\/jpeg","size":1247228,"path_740":"http:\/\/hg.gatech.edu\/sites\/default\/files\/styles\/740xx_scale\/public\/images\/Hyun%20%28Michel%29%20Koo.JPG?itok=LOqVfkEm"}}},"media_ids":["635577","635579","635578"],"related_links":[{"url":"https:\/\/penntoday.upenn.edu\/news\/cavity-causing-bacteria-assemble-army-protective-microbes-human-teeth","title":"Cavity-causing bacteria assemble an army of protective microbes on human teeth "},{"url":"https:\/\/biosciences.gatech.edu\/people\/marvin-whiteley","title":"The Whiteley Lab"},{"url":"https:\/\/cosmosmagazine.com\/science\/biology\/bacteria-seek-safety-before-attacking-your-teeth\/","title":"Bacteria seek safety before attacking teeth"},{"url":"http:\/\/www.news.gatech.edu\/2019\/09\/09\/periodontitis-bacteria-love-colon-and-dirt-microbes","title":"Periodontitis Bacteria Love Colon and Dirt Microbes"},{"url":"https:\/\/cos.gatech.edu\/news\/researchers-team-microbial-dynamics-and-infection","title":"Researchers Team Up for Microbial Dynamics and Infection"}],"groups":[{"id":"620089","name":"Center for Microbial Dynamics and Infection (CMDI)"},{"id":"1278","name":"College of Sciences"},{"id":"1275","name":"School of Biological Sciences"}],"categories":[{"id":"138","name":"Biotechnology, Health, Bioengineering, Genetics"},{"id":"135","name":"Research"}],"keywords":[{"id":"7572","name":"microbes"},{"id":"188231","name":"CMDI"},{"id":"7077","name":"bacteria"},{"id":"184875","name":"cavities"},{"id":"172754","name":"Marvin Whiteley"},{"id":"174250","name":"dental health"},{"id":"182266","name":"Periodontal Disease"},{"id":"182267","name":"Periodontitis"},{"id":"181944","name":"human health"}],"core_research_areas":[{"id":"39441","name":"Bioengineering and Bioscience"}],"news_room_topics":[],"event_categories":[],"invited_audience":[],"affiliations":[],"classification":[],"areas_of_expertise":[],"news_and_recent_appearances":[],"phone":[],"contact":[{"value":"\u003Cp\u003E\u003Ca href=\u0022mailto:jess@cos.gatech.edu\u0022\u003EJess Hunt-Ralston\u003C\/a\u003E\u003Cbr \/\u003E\r\nDirector of Communications\u003Cbr \/\u003E\r\nCollege of Sciences at Georgia Tech\u003C\/p\u003E\r\n","format":"limited_html"}],"email":["jess@cos.gatech.edu"],"slides":[],"orientation":[],"userdata":""}}}