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Estudi De L'expressió I Funció De Les Ribonucleotidil Reductases D'escherichia Coli

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Estudi De L'expressió I Funció De Les Ribonucleotidil Reductases D'escherichia Coli Estudi de l'expressió i funció de les Ribonucleotidil Reductases d'Escherichia coli María del Mar Cendra Gascón ADVERTIMENT. La consulta d’aquesta tesi queda condicionada a l’acceptació de les següents condicions d'ús: La difusió d’aquesta tesi per mitjà del servei TDX (www.tdx.cat) i a través del Dipòsit Digital de la UB (diposit.ub.edu) ha estat autoritzada pels titulars dels drets de propietat intel·lectual únicament per a usos privats emmarcats en activitats d’investigació i docència. No s’autoritza la seva reproducció amb finalitats de lucre ni la seva difusió i posada a disposició des d’un lloc aliè al servei TDX ni al Dipòsit Digital de la UB. No s’autoritza la presentació del seu contingut en una finestra o marc aliè a TDX o al Dipòsit Digital de la UB (framing). Aquesta reserva de drets afecta tant al resum de presentació de la tesi com als seus continguts. En la utilització o cita de parts de la tesi és obligat indicar el nom de la persona autora. ADVERTENCIA. La consulta de esta tesis queda condicionada a la aceptación de las siguientes condiciones de uso: La difusión de esta tesis por medio del servicio TDR (www.tdx.cat) y a través del Repositorio Digital de la UB (diposit.ub.edu) ha sido autorizada por los titulares de los derechos de propiedad intelectual únicamente para usos privados enmarcados en actividades de investigación y docencia. No se autoriza su reproducción con finalidades de lucro ni su difusión y puesta a disposición desde un sitio ajeno al servicio TDR o al Repositorio Digital de la UB. No se autoriza la presentación de su contenido en una ventana o marco ajeno a TDR o al Repositorio Digital de la UB (framing). Esta reserva de derechos afecta tanto al resumen de presentación de la tesis como a sus contenidos. En la utilización o cita de partes de la tesis es obligado indicar el nombre de la persona autora. WARNING. On having consulted this thesis you’re accepting the following use conditions: Spreading this thesis by the TDX (www.tdx.cat) service and by the UB Digital Repository (diposit.ub.edu) has been authorized by the titular of the intellectual property rights only for private uses placed in investigation and teaching activities. Reproduction with lucrative aims is not authorized nor its spreading and availability from a site foreign to the TDX service or to the UB Digital Repository. Introducing its content in a window or frame foreign to the TDX service or to the UB Digital Repository is not authorized (framing). Those rights affect to the presentation summary of the thesis as well as to its contents. In the using or citation of parts of the thesis it’s obliged to indicate the name of the author. Departament de Microbiologia Facultat de Biologia Estudi de l’expressió i funció de les Ribonucleotidil Reductases d’Escherichia coli Maria del Mar Cendra Gascón Tesi Doctoral Barcelona 2013 Departament de Microbiologia Facultat de Biologia Estudi de l’expressió i funció de les Ribonucleotidil Reductases d’Escherichia coli Memòria presentada per Maria del Mar Cendra Gascón per optar al grau de Doctor per la Universitat de Barcelona Programa de Doctorat: Microbiologia Ambiental i Biotecnologia Memòria presentada per: Maria del Mar Cendra Gascón Conformitat del director de Tesi: Conformitat del tutor de Tesi: Dr. Eduard Torrents Serra Dra. Cristina Madrid Xufré AgraïmentsAgraïments Agraïments AgraïmentsAgraïments Agraïments Després d’escriure la Tesi semblava que lo dels agraïments seria cosa fàcil... I la veritat és que no sé per on començar. Primer de tot vull agrair al Prof. Antonio Juàrez per obrir-me la porta a entrar al seu grup d’investigació ara fa 5 anys, i a la Dra. Cristina Madrid per ser la primera supervisora que vaig tenir quan vaig entrar a col·laborar al Departament de Microbiologia. Especialment, vull agrair al Dr. Eduard Torrents per donar-me la oportunitat de fer aquesta tesi doctoral. Al llarg d’aquests gairebé 5 anys hi han hagut moments de tot, i ell, a les dures i a les madures, ha estat allà. La gent amb la que he compartit aquests anys ha estat molt diversa, inicialment al IBEC amb la Laura, la Rosa i la Nahia (quins riures que fèiem eh...!). I també amb la Mary i després amb la Núria, l’Íngrid i amb l’Ana Oliva! Amb qui també hem compartit molt bons moments. Ja més tard amb la Manu who I consider a very good friend inside and also outside of the lab, la Francesca, l’Ariadna, el David i també el Mário, primer al departament i ara a l’IBEC, que sempre m’ha ajudat quan li he preguntat qualsevol cosa. Amb molt afecte vull mencionar a l’Anna, que ha estat present al llarg de tots aquest anys de treball, començant a col·laborar en el grup el mateix estiu que jo vaig començar el doctorat, i a qui he vist “créixer” al laboratori. Ella de tant en tant encara diu que sóc una mica la seva “jefa”, tot i que les dues sabem que en veritat som molt bones amigues. De l’IBEC també vull mencionar al grup “JAR” que sempre m’ha ajudat quan he necessitat alguna cosa, i especialment a la Vane i a l’Òscar. També és molt important anomenar l’AitorT! Que més que agrair-li alguna cosa crec que ell m’hauria d’agrair a mi la paciència que tinc amb ell!! jajaja ara en serio, t’has convertit en un gran amic Aitor. I les Infraestructures girls! Amb la Isabel, Laura i últimament amb la Cris! Molt amables amb mi en tot moment. Encara que hagi fet la tesi a l’IBEC, inicialment vaig estar al Departament de Microbiologia i no puc no mencionar a la Carla, Marta, Llorenç, Juanda, Jorge, ja una mica més tard la Tania i com no, les dos Sònies. La Sònia Aznar (encara recordo com si fos ahir quan et vaig conèixer el meu primer dia) una gran persona i que encara que amb el temps ens hem anat veient menys, li guardo un gran afecte. I també a la Sònia Paytubi, qui m’ha introduït al món Prosperil i s’ha convertit en una gran amiga. Agraïments I els meus amics! Tant els biologuitos com els de Vilanova! Especialment vull mencionar al Robert, Nahia, Ainhoa, Elvira, Aina, Laura, Anna, Núria, Murci, Mireia Mayo, Mireia Serra, Marta Caminoli i a l’Ana. Que m’han ajudat i han tingut molta paciència quan els hi comentava alguna cosa de la feina i els intentava explicar en què consistia el que faig i també quan els hi ensenyava a dir: Ribonucleotidil Reductasa d’una tirada! que en serio... no és cosa fàcil. Ja per últim les persones més importants, vull agrair al meu germà i als meus pares el seu recolzament i ajut incondicional, ja no només durant aquest període de doctorat, sinó en tot el que faig. Als meus pares Índex Índex 1 ÍNDEX 2 ABREVIATURES ................................................................................................ 21 3 INTRODUCCIÓ .................................................................................................. 27 3.1 LA RIBONUCLEOTIDIL REDUCTASA (RNR) ....................................................... 27 3.1.1 INTRODUCCIÓ A L’ENZIM ................................................................................ 27 3.1.2 CLASSES DE L’ENZIM ....................................................................................... 28 3.1.3 REGULACIÓ AL·LOSTÈRICA ............................................................................ 31 3.1.4 MECANISME CATALÍTIC .................................................................................. 34 3.1.4.1 Mecanisme de regeneració del poder reductor de les cisteïnes .................... 35 3.1.4.1.1 Sistema de tioredoxines ............................................................................... 37 3.1.4.1.2 Sistema de glutaredoxines ........................................................................... 37 3.1.4.2 Diferències en el Mecanisme catalític entre classes de RNR ....................... 38 3.1.4.2.1 Mecanisme catalític de la RNR de classe Ia ................................................ 39 3.1.4.2.2 Mecanisme catalític classe Ib ...................................................................... 39 3.1.4.2.3 Mecanisme catalític classe Ic ...................................................................... 41 3.1.4.3 Mecanisme catalític classe II ........................................................................ 41 3.1.4.4 Mecanisme catalític classe III ....................................................................... 42 3.1.5 ESTRUCTURA TRIDIMENSIONAL DE LES RNR ................................................ 44 3.1.5.1 Classe Ia ........................................................................................................ 44 3.1.5.2 Classe Ib ........................................................................................................ 48 3.1.5.3 Classe Ic ........................................................................................................ 51 3.1.5.4 Classe II ........................................................................................................ 52 3.1.5.5 Classe III ....................................................................................................... 54 3.1.6 EVOLUCIÓ DE LES TRES CLASSES DE RNR ..................................................... 57 3.2 LES DIFERENTS CLASSES DE RNR D’ESCHERICHIA COLI: IA, IB I III ................ 60 3.2.1 LA RNR DE CLASSE I: CLASSE IA ................................................................... 60 3.2.1.1 Organització gènica ...................................................................................... 60 3.2.1.2 Regulació transcripcional .............................................................................. 60 3.2.2 LA RNR DE CLASSE I: CLASSE IB
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