{"id":109526,"date":"2018-03-11T10:34:59","date_gmt":"2018-03-11T10:34:59","guid":{"rendered":"https:\/\/www.deberes.net\/tesis\/sin-categoria\/epidemiologa%c2%ada-molecular-y-bases-geneticas-de-la-resistencia-y-virulencia-de-staphylococcus-aureus-de-diferente-origen\/"},"modified":"2018-03-11T10:34:59","modified_gmt":"2018-03-11T10:34:59","slug":"epidemiologa%c2%ada-molecular-y-bases-geneticas-de-la-resistencia-y-virulencia-de-staphylococcus-aureus-de-diferente-origen","status":"publish","type":"post","link":"https:\/\/www.deberes.net\/tesis\/microbiologia\/epidemiologa%c2%ada-molecular-y-bases-geneticas-de-la-resistencia-y-virulencia-de-staphylococcus-aureus-de-diferente-origen\/","title":{"rendered":"Epidemiolog\u00eda molecular y bases gen\u00e9ticas de la resistencia y virulencia de staphylococcus aureus de diferente origen"},"content":{"rendered":"<h2>Tesis doctoral de <strong> Mar\u00eda De Los \u00e1ngeles Argud\u00edn Regueiro <\/strong><\/h2>\n<p>Staphylococcus aureus es una bacteria comensal y pat\u00f3gena, que se encuentra en el ser humano y en animales tanto en estado portador como causando enfermedad. Su estructura poblacional es altamente clonal, lo que est\u00e1 facilitado por la presencia de sistemas de restricci\u00f3n-modificaci\u00f3n (rm) que modulan el intercambio gen\u00e9tico. A pesar de ello, existen fen\u00f3menos de transferencia horizontal que permiten la dispersi\u00f3n o intercambio de elementos gen\u00e9ticos m\u00f3viles (egm) y sistemas reguladores entre clones del mismo linaje e incluso de diferentes linajes. La presente tesis doctoral analiza la estructura poblacional de una amplia colecci\u00f3n de aislamientos de s. Aureus de diverso origen (humano, alimentos y animales) y examina la distribuci\u00f3n de determinantes de resistencia y virulencia entre los linajes encontrados. Los aislamientos analizados proceden de pacientes de dos hospitales, de portadores sanos, de muestras de alimentos y de manipuladores de alimentos, todos ellos del principado de asturias (pa). Tambi\u00e9n se incluyeron en el estudio aislamientos de origen animal de alemania, pertenecientes al clon emergente st398\/cc398. Los aspectos desarrollados fueron los siguientes: 1. Identificaci\u00f3n de los linajes circulantes en el pa y de su variabilidad interna mediante el uso de distintas t\u00e9cnicas de tipificaci\u00f3n: electroforesis en campo pulsante (pfge), secuenciaci\u00f3n de m\u00faltiples loci (mlst), secuenciaci\u00f3n del gen de la prote\u00edna a (spa) y amplificaci\u00f3n de los genes sau1hsds1 y sau1hsds2 del sistema rm sau1. Se estableci\u00f3 la presencia de 15 linajes en la regi\u00f3n (cc1, cc5, cc8, cc9, cc12, cc15, cc22, cc25, cc30, cc45, cc59, cc72, cc88, cc97, cc121) siendo mayoritarios cc5, cc30 y cc45. Adem\u00e1s, se desarroll\u00f3 un protocolo para la tipificaci\u00f3n por pfge del clon emergente st398 no tipificable anteriormente con esta t\u00e9cnica. 2. Detecci\u00f3n de determinantes de virulencia y de egm implicados en su dispersi\u00f3n. A diferencia del clon st398, los aislamientos del pa presentaron un n\u00famero muy elevado de determinantes de virulencia asociados a emg (islas gen\u00f3micas, islas de patogenicidad, profagos, y pl\u00e1smidos), combinados en numerosos perfiles. Estos resultados ponen de manifiesto la elevada plasticidad del genoma de s. Aureus, lo cual facilita su adaptaci\u00f3n a los distintos nichos ecol\u00f3gicos que ocupa. Este apartado se complet\u00f3 con la caracterizaci\u00f3n molecular de un pl\u00e1smido hibrido de virulencia-resistencia, que representa un interesante ejemplo de ingenier\u00eda evolutiva. 3. Estudios de resistencia. Se encontraron elevados porcentajes de resistencia, especialmente frente a \u00edY-lact\u00e1micos, aminoglicosidos, macr\u00f3lidos y lincosamidas, y de multirresistencia, en aislamientos cl\u00ednicos del pa y en cc398, con respecto a los aislamientos recogidos en la comunidad. Se identificaron los genes responsables de las resistencias y los egm implicados en su dispersi\u00f3n (transposones y pl\u00e1smidos), y se estableci\u00f3 su distribuci\u00f3n en los diferentes linajes. La determinaci\u00f3n de los tipos sccmec en aislamientos resistentes a meticilina permiti\u00f3 identificar los clones mrsa circulantes en la regi\u00f3n y dentro del cc398. la tesis doctoral amplia el conocimiento sobre la estructura poblacional de s. Aureus, y sobre las propiedades de resistencia y virulencia de los linajes y clones detectados. Adem\u00e1s, identific\u00f3 los clones epid\u00e9micos, espor\u00e1dicos y emergentes que han estado circulando en el pa, cuyo seguimiento epidemiol\u00f3gico debe continuar en el futuro.     staphylococcus aureus is both a commensal and a pathogenic bacterium, able to cause disease or to establish a carrier state in humans and animals. S. Aureus has a highly clonal population structure, which is facilitated by the presence of restriction-modification (rm) systems that modulate the genetic exchange. However, horizontal transfer events can occur allowing the spread or exchange of mobile genetic elements (mge) and regulatory systems between clones of the same and even different lineages. This doctoral thesis analyzes the population structure of a large collection of isolates of s. Aureus from different origins (human, animal and food), and examines the distribution of resistance and virulence determinants among different lineages. The isolates analyzed were recovered from human clinical samples in two hospitals, healthy carriers, food samples and food handlers in the principality of asturias (pa). Isolates collected in germany from animal samples and belonging mainly to the emerging st398\/cc398 clone were also analyzed. The main objectives of the thesis were the following: 1. Identification of the clones and lineages which have been circulating in the pa, both in nosocomial and community settings, and its internal variability using different typing techniques: pulsed field gel electrophoresis (pfge), multilocus sequence typing (mlst), protein a gene (spa) typing, and pcr amplification of the sau1hsds1 and sau1hsds2 of the sau1 rm system. By these means, 15 lineages (cc1, cc5, cc8, cc9, cc12, cc15, cc22, cc25, cc30, cc45, cc59, cc72, cc88, cc97, cc121) were detected in our region, with cc5, cc30 and cc45 being predominant. Moreover, we developed a new typing pfge protocol for cc398, which was previously untypeable by this technique. 2. Detection of virulence determinants and mges involved in their spread. In contrast to cc398, the isolates from the pa carried a large number of virulence genes, associated with mges, such as genomic islands, pathogenicity islands, prophages and plasmids, and arranged in many different combinations. These results reveal the high plasticity of the s. Aureus genome, which can be viewed as a means of adaptation to the different ecological niches that can be colonized by this bacterium. These studies were complemented with the characterization of a hybrid virulence-resistance plasmid, which represents an interesting example of evolutionary engineering in s. Aureus. 3. Resistance studies. High rates of resistance, particularly against \u00edY-lactams, aminoglycosides, macrolides and lincosamides, as well as multidrug resistance, were found in clinical isolates recovered in the pa and the cc398 clone, in comparison to isolates recovered in the community. The genes responsible for the resistances detected, and the mges involved in their spread (transposons and plasmids), were identified and their distribution among different lineages and clones was established. Determination of the sccmec types in methicillin-resistant isolates led to the identification of the mrsa clones circulating in the pa and within cc398. this doctoral thesis increases the existing knowledge on the population structure of s. Aureus, and on its resistance and virulence properties. It supplies information on the epidemic, sporadic and emerging clones which have been circulating in the pa, and highlights the importance of further epidemiological surveillance.<\/p>\n<p>&nbsp;<\/p>\n<h3>Datos acad\u00e9micos de la tesis doctoral \u00ab<strong>Epidemiolog\u00eda molecular y bases gen\u00e9ticas de la resistencia y virulencia de staphylococcus aureus de diferente origen<\/strong>\u00ab<\/h3>\n<ul>\n<li><strong>T\u00edtulo de la tesis:<\/strong>\u00a0 Epidemiolog\u00eda molecular y bases gen\u00e9ticas de la resistencia y virulencia de staphylococcus aureus de diferente origen <\/li>\n<li><strong>Autor:<\/strong>\u00a0 Mar\u00eda De Los \u00e1ngeles Argud\u00edn Regueiro <\/li>\n<li><strong>Universidad:<\/strong>\u00a0 Oviedo<\/li>\n<li><strong>Fecha de lectura de la tesis:<\/strong>\u00a0 27\/06\/2011<\/li>\n<\/ul>\n<p>&nbsp;<\/p>\n<h3>Direcci\u00f3n y tribunal<\/h3>\n<ul>\n<li><strong>Director de la tesis<\/strong>\n<ul>\n<li>Mar\u00eda Cruz Mart\u00edn Mart\u00edn<\/li>\n<\/ul>\n<\/li>\n<li><strong>Tribunal<\/strong>\n<ul>\n<li>Presidente del tribunal: fernando Vazquez valdes <\/li>\n<li>maximiliano Alvarez fernandez (vocal)<\/li>\n<li>bernd-alois Tenhagen (vocal)<\/li>\n<li>carmen Torres manrique (vocal)<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<p>&nbsp;<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Tesis doctoral de Mar\u00eda De Los \u00e1ngeles Argud\u00edn Regueiro Staphylococcus aureus es una bacteria comensal y pat\u00f3gena, que se encuentra [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"default","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"var(--ast-global-color-4)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""}},"footnotes":""},"categories":[36606,1086,278,8846],"tags":[219043,24216,64695,219042,219041,141770],"class_list":["post-109526","post","type-post","status-publish","format-standard","hentry","category-biologia-molecular-de-microorganismos","category-epidemiologia","category-microbiologia","category-oviedo","tag-bernd-alois-tenhagen","tag-carmen-torres-manrique","tag-fernando-vazquez-valdes","tag-maria-cruz-martin-martin","tag-maria-de-los-angeles-argudin-regueiro","tag-maximiliano-alvarez-fernandez"],"_links":{"self":[{"href":"https:\/\/www.deberes.net\/tesis\/wp-json\/wp\/v2\/posts\/109526","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.deberes.net\/tesis\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.deberes.net\/tesis\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.deberes.net\/tesis\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.deberes.net\/tesis\/wp-json\/wp\/v2\/comments?post=109526"}],"version-history":[{"count":0,"href":"https:\/\/www.deberes.net\/tesis\/wp-json\/wp\/v2\/posts\/109526\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.deberes.net\/tesis\/wp-json\/wp\/v2\/media?parent=109526"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.deberes.net\/tesis\/wp-json\/wp\/v2\/categories?post=109526"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.deberes.net\/tesis\/wp-json\/wp\/v2\/tags?post=109526"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}