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You searched for subject:(Genomic islet ). Showing records 1 – 2 of 2 total matches.

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1. Mannoubi, Soumaya. Caractérisation de MamK et Mamk-like les "actins-like" responsables de l'alignement des magnétosomes chez Magnetsirillum magneticum AMB-1 : Characterization of MamK and MamK-like the "actins-like" responsible for the alignment of magnetosomes in Magnetospirillum magneticum AMB-1.

Degree: Docteur es, Microbiologie, 2014, Aix Marseille Université

Les bactéries magnétotactiques (MTB) ont la capacité de s'orienter dans un champ magnétique grâce à un organite procaryote constitué d'un nanocristal magnétique biominéralisé et entouré d'une membrane biologique : le magnétosome. La synthèse de cet organite est un processus complexe contrôlé génétiquement par une série de gènes spécifiques aux MTB (les gènes mam) qui sont regroupés sur le chromosome bactérien. Chez la souche modèle Magnetospirillum magneticum AMB-1 cet ensemble de gènes forme un îlot génomique (MAI) auquel s'ajoute un second groupe distinct de 7 gènes homologues aux gènes mam (gènes mam-like) récemment identifié dont le rôle physiologique est très peu caractérisé. Parmi les produits des gènes mam, MamK est impliqué dans l'alignement des magnétosomes. Cette « actin-like » prokaryote qui forme des filaments selon un processus ATP-dépendant a été caractérisée ces dernières années. Dans le MIS de AMB-1, un gène homologue mamK-like a été identifié. Ainsi différentes approches pluridisciplinaires ont été mises en place pour comprendre le rôle de MamK et MamK-like. L'expression des gènes du MIS a été quantifiée. Les souches dépourvues des gènes mamK et mamK-like ainsi que le double mutant ont été obtenues puis phénotypées par différentes techniques d'imagerie. Les interactions entre les deux protéines ont été également testées. Enfin, les deux protéines ont été et leurs propriétés biochimiques caractérisées. L'ensemble de ces données nous permet de proposer un modèle selon lequel MamK et MamK-like participeraient tous deux à l'alignement des magnétosomes bactériens, vraisemblablement par la formation de filaments hybrides.

Magnetotactic bacteria (MTB) have the ability to orient in a magnetic field through a prokaryotic organelle composed of a magnetic nanocrystal surrounded by a biological membrane: the magnetosome. The synthesis of this organelle is a genetically complex process controlled by a series of specific genes (mam genes) grouped together on the bacterial chromosome. In the strain model Magnetospirillum magneticum AMB-1 this set of genes form a genomic island (MAI) and a second distinct group of seven genes homologous to mam genes (mam-like genes) recently identified. The physiological role of this islet magnetosome (MIS) is very little characterized to date.Among the products of mam genes, MamK is involved in the alignment of the magnetosomes. This « actin-like » which forms prokaryote filaments according an ATP - dependent process has been characterized in recent years. In the MIS of AMB-1, a homologous gene mamK-like was identified. And various multidisciplinary approaches have been developed to understand the role of MamK and MamK-like. The MIS gene expression was quantified. The strains lacking genes of mamK, mamK-like and the obtained of double mutant were then phenotyped by different imaging techniques. The interactions between the two proteins were also tested. Finally, the two proteins were overexpressed and their biochemical properties characterized. All of these data allows us to…

Advisors/Committee Members: Pignol, David (thesis director).

Subjects/Keywords: « actin-Like »; Magnetosome; ATpase; Polymérisation; Filaments; Îlot génomique; Îlet génomique.; « actin-Like »; Magnetosome; ATPase; Polymerization; Filaments; Genomic island; Genomic islet.; 579

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Mannoubi, S. (2014). Caractérisation de MamK et Mamk-like les "actins-like" responsables de l'alignement des magnétosomes chez Magnetsirillum magneticum AMB-1 : Characterization of MamK and MamK-like the "actins-like" responsible for the alignment of magnetosomes in Magnetospirillum magneticum AMB-1. (Doctoral Dissertation). Aix Marseille Université. Retrieved from http://www.theses.fr/2014AIXM4004

Chicago Manual of Style (16th Edition):

Mannoubi, Soumaya. “Caractérisation de MamK et Mamk-like les "actins-like" responsables de l'alignement des magnétosomes chez Magnetsirillum magneticum AMB-1 : Characterization of MamK and MamK-like the "actins-like" responsible for the alignment of magnetosomes in Magnetospirillum magneticum AMB-1.” 2014. Doctoral Dissertation, Aix Marseille Université. Accessed October 13, 2019. http://www.theses.fr/2014AIXM4004.

MLA Handbook (7th Edition):

Mannoubi, Soumaya. “Caractérisation de MamK et Mamk-like les "actins-like" responsables de l'alignement des magnétosomes chez Magnetsirillum magneticum AMB-1 : Characterization of MamK and MamK-like the "actins-like" responsible for the alignment of magnetosomes in Magnetospirillum magneticum AMB-1.” 2014. Web. 13 Oct 2019.

Vancouver:

Mannoubi S. Caractérisation de MamK et Mamk-like les "actins-like" responsables de l'alignement des magnétosomes chez Magnetsirillum magneticum AMB-1 : Characterization of MamK and MamK-like the "actins-like" responsible for the alignment of magnetosomes in Magnetospirillum magneticum AMB-1. [Internet] [Doctoral dissertation]. Aix Marseille Université 2014. [cited 2019 Oct 13]. Available from: http://www.theses.fr/2014AIXM4004.

Council of Science Editors:

Mannoubi S. Caractérisation de MamK et Mamk-like les "actins-like" responsables de l'alignement des magnétosomes chez Magnetsirillum magneticum AMB-1 : Characterization of MamK and MamK-like the "actins-like" responsible for the alignment of magnetosomes in Magnetospirillum magneticum AMB-1. [Doctoral Dissertation]. Aix Marseille Université 2014. Available from: http://www.theses.fr/2014AIXM4004


Lincoln University

2. Panda, Preetinanda. The role of genomic islands in virulence of Pectobacterium carotovorum subspecies brasiliensis on potatoes.

Degree: 2014, Lincoln University

Pectobacterium carotovorum subsp. carotovorum is primarily responsible for soft rotting of potato tubers, although several strains have been shown to cause blackleg of potato stems. In contrast, P. atrosepticum is best known as a seedborne pathogen that causes blackleg. It is also responsible for soft rotting of tubers. Given the taxonomic distance between these two species and that only some strains of P. carotovorum subsp. carotovorum are able to cause blackleg, it was hypothesised that the capacity of P. carotovorum subsp. carotovorum to invade potato stems and elicit blackleg may have evolved through independent acquisition of genomic islands (GIs). GIs are large chromosomal regions in bacteria that are acquired by horizontal gene transfer and often encode virulence factors. To address this hypothesis, the genomes of P. carotovorum subsp. carotovorum strains associated with blackleg disease of potatoes were compared to those of non-blackleg causing strains, to identify GIs in blackleg causing strains and novel virulence factors encoded on these islands. First, the identity of a highly aggressive P. carotovorum subsp. carotovorum strain ICMP19477 and other New Zealand isolates known to cause blackleg, was re-assessed using molecular and phylogenetic assays. These assays identified the isolates as P. carotovorum subsp. brasiliensis. Comparative genomics using the genome sequence obtained for ICMP19477 and three other Pectobacterium in this study, as well as the genomes of 10 soft rot erwiniae (SRE) obtained from public databases, identified a total of 69 genomic islands and 10 gene islets in the genome of ICMP19477. Many of these islands and islets harboured genes predicted to be associated with the virulence of this pathogen (e.g. genes encoding putative plant cell wall degrading enzymes, phytotoxins, secretion systems, sugar utilisation, etc.), yet only one was present exclusively in the P. atrosepticum and P. carotovorum subsp. brasiliensis isolates historically known to cause blackleg. This islet (sim gene islet) encodes a sugar:phosphotransferase system, which is important in the pathogenicity of vascular plant pathogens such as Erwinia amylovora. The majority of other GIs and islets carrying putative virulence genes were either not present in the genomes of all blackleg causing strains or were present in strains that did not cause blackleg (e.g. GI PbN1_GI24, which encoded a putative non-ribosomal peptide with similarity to syringomycin). To confirm the role of several putative virulence factors in virulence of P. carotovorum subsp. brasiliensis ICMP19477, knockout mutants were constructed by allelic exchange mutagenesis. Mutations in the non-ribosomal peptide synthetase cluster of P. carotovorum subsp. brasiliensis (on PbN1_GI24) did not result in significant differences in virulence of the wild type and the mutant in pathogenicity assays on potato. In contrast, single crossover mutants in the islets encoding the sugar:phosphotransferase system and phenolic acid decarboxylase significantly… Advisors/Committee Members: Pitman, Andrew.

Subjects/Keywords: Pectobacterium; blackleg; soft rot; genomic island; gene islet; horizontal gene transfer; sugar:phosphotransferase system; phenolic acid decarboxylase; virulence; genomics

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Panda, P. (2014). The role of genomic islands in virulence of Pectobacterium carotovorum subspecies brasiliensis on potatoes. (Thesis). Lincoln University. Retrieved from http://hdl.handle.net/10182/6637

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16th Edition):

Panda, Preetinanda. “The role of genomic islands in virulence of Pectobacterium carotovorum subspecies brasiliensis on potatoes.” 2014. Thesis, Lincoln University. Accessed October 13, 2019. http://hdl.handle.net/10182/6637.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7th Edition):

Panda, Preetinanda. “The role of genomic islands in virulence of Pectobacterium carotovorum subspecies brasiliensis on potatoes.” 2014. Web. 13 Oct 2019.

Vancouver:

Panda P. The role of genomic islands in virulence of Pectobacterium carotovorum subspecies brasiliensis on potatoes. [Internet] [Thesis]. Lincoln University; 2014. [cited 2019 Oct 13]. Available from: http://hdl.handle.net/10182/6637.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Panda P. The role of genomic islands in virulence of Pectobacterium carotovorum subspecies brasiliensis on potatoes. [Thesis]. Lincoln University; 2014. Available from: http://hdl.handle.net/10182/6637

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

.