Academic literature on the topic 'Integrative Conjugative Elements (ICEs)'
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Journal articles on the topic "Integrative Conjugative Elements (ICEs)":
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Bellanger, Xavier, Adam P. Roberts, Catherine Morel, Frédéric Choulet, Guillaume Pavlovic, Peter Mullany, Bernard Decaris, and Gérard Guédon. "Conjugative Transfer of the Integrative Conjugative Elements ICESt1 and ICESt3 from Streptococcus thermophilus." Journal of Bacteriology 191, no. 8 (January 30, 2009): 2764–75. http://dx.doi.org/10.1128/jb.01412-08.
Abstract:
ABSTRACT Integrative and conjugative elements (ICEs), also called conjugative transposons, are genomic islands that excise, self-transfer by conjugation, and integrate in the genome of the recipient bacterium. The current investigation shows the intraspecies conjugative transfer of the first described ICEs in Streptococcus thermophilus, ICESt1 and ICESt3. Mitomycin C, a DNA-damaging agent, derepresses ICESt3 conjugative transfer almost 25-fold. The ICESt3 host range was determined using various members of the Firmicutes as recipients. Whereas numerous ICESt3 transconjugants of Streptococcus pyogenes and Enterococcus faecalis were recovered, only one transconjugant of Lactococcus lactis was obtained. The newly incoming ICEs, except the one from L. lactis, are site-specifically integrated into the 3′ end of the fda gene and are still able to excise in these transconjugants. Furthermore, ICESt3 was retransferred from E. faecalis to S. thermophilus. Recombinant plasmids carrying different parts of the ICESt1 recombination module were used to show that the integrase gene is required for the site-specific integration and excision of the ICEs, whereas the excisionase gene is required for the site-specific excision only.
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Zakharova, I. B., and D. V. Viktorov. "Integrative conjugative elements (ICEs) of microorganisms." Molecular Genetics, Microbiology and Virology 30, no. 3 (July 2015): 114–23. http://dx.doi.org/10.3103/s0891416815030076.
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Iannelli, Francesco, Francesco Santoro, Marco R. Oggioni, and Gianni Pozzi. "Nucleotide Sequence Analysis of Integrative Conjugative Element Tn5253of Streptococcus pneumoniae." Antimicrobial Agents and Chemotherapy 58, no. 2 (December 2, 2013): 1235–39. http://dx.doi.org/10.1128/aac.01764-13.
Abstract:
ABSTRACTConjugative transposon Tn5253, an integrative conjugative element (ICE) ofStreptococcus pneumoniaecarrying thecatandtet(M) genes, was shown to be 64,528 bp in size and to contain 79 open reading frames, of which only 38 could be annotated. Two distinct genetic elements were found integrated into Tn5253: Tn5251(18,033 bp), of the Tn916-Tn1545family of ICEs, and Ωcat(pC194) (7,627 bp), which could not conjugate but was capable of intracellular mobility by excision, circularization, and integration by homologous recombination. The highest conjugation frequency of Tn5253was observed whenStreptococcus pyogeneswas the donor (6.7 × 10−3transconjugants/donor).
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Bioteau, Audrey, Romain Durand, and Vincent Burrus. "Redefinition and Unification of the SXT/R391 Family of Integrative and Conjugative Elements." Applied and Environmental Microbiology 84, no. 13 (April 13, 2018): e00485-18. http://dx.doi.org/10.1128/aem.00485-18.
Abstract:
ABSTRACT Integrative and conjugative elements (ICEs) of the SXT/R391 family are key drivers of the spread of antibiotic resistance in Vibrio cholerae, the infectious agent of cholera, and other pathogenic bacteria. The SXT/R391 family of ICEs was defined based on the conservation of a core set of 52 genes and site-specific integration into the 5′ end of the chromosomal gene prfC. Hence, the integrase gene int has been intensively used as a marker to detect SXT/R391 ICEs in clinical isolates. ICEs sharing most core genes but differing by their integration site and integrase gene have been recently reported and excluded from the SXT/R391 family. Here we explored the prevalence and diversity of atypical ICEs in GenBank databases and their relationship with typical SXT/R391 ICEs. We found atypical ICEs in V. cholerae isolates that predate the emergence and expansion of typical SXT/R391 ICEs in the mid-1980s in seventh-pandemic toxigenic V. cholerae strains O1 and O139. Our analyses revealed that while atypical ICEs are not associated with antibiotic resistance genes, they often carry cation efflux pumps, suggesting heavy metal resistance. Atypical ICEs constitute a polyphyletic group likely because of occasional recombination events with typical ICEs. Furthermore, we show that the alternative integration and excision genes of atypical ICEs remain under the control of SetCD, the main activator of the conjugative functions of SXT/R391 ICEs. Together, these observations indicate that substitution of the integration/excision module and change of specificity of integration do not preclude atypical ICEs from inclusion into the SXT/R391 family. IMPORTANCE Vibrio cholerae is the causative agent of cholera, an acute intestinal infection that remains to this day a world public health threat. Integrative and conjugative elements (ICEs) of the SXT/R391 family have played a major role in spreading antimicrobial resistance in seventh-pandemic V. cholerae but also in several species of Enterobacteriaceae. Most epidemiological surveys use the integrase gene as a marker to screen for SXT/R391 ICEs in clinical or environmental strains. With the recent reports of closely related elements that carry an alternative integrase gene, it became urgent to investigate whether ICEs that have been left out of the family are a liability for the accuracy of such screenings. In this study, based on comparative genomics, we broaden the SXT/R391 family of ICEs to include atypical ICEs that are often associated with heavy metal resistance.
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Libante, Virginie, Yves Nombre, Charles Coluzzi, Johan Staub, Gérard Guédon, Marcelo Gottschalk, Sarah Teatero, Nahuel Fittipaldi, Nathalie Leblond-Bourget, and Sophie Payot. "Chromosomal Conjugative and Mobilizable Elements in Streptococcus suis: Major Actors in the Spreading of Antimicrobial Resistance and Bacteriocin Synthesis Genes." Pathogens 9, no. 1 (December 25, 2019): 22. http://dx.doi.org/10.3390/pathogens9010022.
Abstract:
Streptococcus suis is a zoonotic pathogen suspected to be a reservoir of antimicrobial resistance (AMR) genes. The genomes of 214 strains of 27 serotypes were screened for AMR genes and chromosomal Mobile Genetic Elements (MGEs), in particular Integrative Conjugative Elements (ICEs) and Integrative Mobilizable Elements (IMEs). The functionality of two ICEs that host IMEs carrying AMR genes was investigated by excision tests and conjugation experiments. In silico search revealed 416 ICE-related and 457 IME-related elements. These MGEs exhibit an impressive diversity and plasticity with tandem accretions, integration of ICEs or IMEs inside ICEs and recombination between the elements. All of the detected 393 AMR genes are carried by MGEs. As previously described, ICEs are major vehicles of AMR genes in S. suis. Tn5252-related ICEs also appear to carry bacteriocin clusters. Furthermore, whereas the association of IME-AMR genes has never been described in S. suis, we found that most AMR genes are actually carried by IMEs. The autonomous transfer of an ICE to another bacterial species (Streptococcus thermophilus)—leading to the cis-mobilization of an IME carrying tet(O)—was obtained. These results show that besides ICEs, IMEs likely play a major role in the dissemination of AMR genes in S. suis.
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Lei, Chang-Wei, An-Yun Zhang, Hong-Ning Wang, Bi-Hui Liu, Li-Qin Yang, and Yong-Qiang Yang. "Characterization of SXT/R391 Integrative and Conjugative Elements in Proteus mirabilis Isolates from Food-Producing Animals in China." Antimicrobial Agents and Chemotherapy 60, no. 3 (January 11, 2016): 1935–38. http://dx.doi.org/10.1128/aac.02852-15.
Abstract:
SXT/R391 integrative and conjugative elements (ICEs) were detected in 8 out of 125Proteus mirabilisisolates from food-producing animals in China. Whole-genome sequencing revealed that seven ICEs were identical to ICEPmiJpn1, carrying the cephalosporinase geneblaCMY-2. Another one, designated ICEPmiChn1, carried five resistance genes. All eight ICEs could be transferred toEscherichia colivia conjugation. The results highlight the idea that animal farms are important reservoir of the SXT/R391 ICE-containingP. mirabilis.
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Haskett, Timothy L., Jason J. Terpolilli, Amanuel Bekuma, Graham W. O’Hara, John T. Sullivan, Penghao Wang, Clive W. Ronson, and Joshua P. Ramsay. "Assembly and transfer of tripartite integrative and conjugative genetic elements." Proceedings of the National Academy of Sciences 113, no. 43 (October 12, 2016): 12268–73. http://dx.doi.org/10.1073/pnas.1613358113.
Abstract:
Integrative and conjugative elements (ICEs) are ubiquitous mobile genetic elements present as “genomic islands” within bacterial chromosomes. Symbiosis islands are ICEs that convert nonsymbiotic mesorhizobia into symbionts of legumes. Here we report the discovery of symbiosis ICEs that exist as three separate chromosomal regions when integrated in their hosts, but through recombination assemble as a single circular ICE for conjugative transfer. Whole-genome comparisons revealed exconjugants derived from nonsymbiotic mesorhizobia received three separate chromosomal regions from the donorMesorhizobium ciceriWSM1271. The three regions were each bordered by two nonhomologous integrase attachment (att) sites, which together comprised three homologous pairs ofattLandattRsites. Sequential recombination between eachattLandattRpair produced correspondingattPandattBsites and joined the three fragments to produce a single circular ICE, ICEMcSym1271. A plasmid carrying the threeattPsites was used to recreate the process of tripartite ICE integration and to confirm the role of integrase genesintS,intM, andintGin this process. Nine additional tripartite ICEs were identified in diverse mesorhizobia and transfer was demonstrated for three of them. The transfer of tripartite ICEs to nonsymbiotic mesorhizobia explains the evolution of competitive but suboptimal N2-fixing strains found in Western Australian soils. The unheralded existence of tripartite ICEs raises the possibility that multipartite elements reside in other organisms, but have been overlooked because of their unusual biology. These discoveries reveal mechanisms by which integrases dramatically manipulate bacterial genomes to allow cotransfer of disparate chromosomal regions.
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Hirose, Jun. "Diversity and Evolution of Integrative and Conjugative Elements Involved in Bacterial Aromatic Compound Degradation and Their Utility in Environmental Remediation." Microorganisms 11, no. 2 (February 9, 2023): 438. http://dx.doi.org/10.3390/microorganisms11020438.
Abstract:
Integrative and conjugative elements (ICEs) are mobile DNA molecules that can be transferred through excision, conjugation, and integration into chromosomes. They contribute to the horizontal transfer of genomic islands across bacterial species. ICEs carrying genes encoding aromatic compound degradation pathways are of interest because of their contribution to environmental remediation. Recent advances in DNA sequencing technology have increased the number of newly discovered ICEs in bacterial genomes and have enabled comparative analysis of their evolution. The two different families of ICEs carry various aromatic compound degradation pathway genes. ICEclc and its related ICEs contain a number of members with diverse catabolic capabilities. In addition, the Tn4371 family, which includes ICEs that carry the chlorinated biphenyl catabolic pathway, has been identified. It is apparent that they underwent evolution through the acquisition, deletion, or exchange of modules to adapt to an environmental niche. ICEs have the property of both stability and mobility in the chromosome. Perspectives on the use of ICEs in environmental remediation are also discussed.
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Dimopoulou, Ioanna D., Sofia I. Kartali, Rosalind M. Harding, Tim E. A. Peto, and Derrick W. Crook. "Diversity of antibiotic resistance integrative and conjugative elements among haemophili." Journal of Medical Microbiology 56, no. 6 (June 1, 2007): 838–46. http://dx.doi.org/10.1099/jmm.0.47125-0.
Abstract:
The objective of this study was to investigate the sequence diversity in a single country of a family of integrative and conjugative elements (ICEs) that are vectors of antibiotic resistance in Haemophilus influenzae and Haemophilus parainfluenzae, and test the hypothesis that they emerged from a single lineage. Sixty subjects aged 9 months – 13 years were recruited and oropharyngeal samples cultured. Up to 10 morphologically distinct Pasteurellaceae spp. were purified, and then the species were determined and differentiated by partial sequence analysis of 16S rDNA and mdh, respectively. ICEs were detected by PCR directed at five genes distributed evenly across the ICE. These amplicons were sequenced and aligned by the neighbour-joining algorithm. A total of 339 distinguishable isolates were cultured. ICEs with all 5 genes present were found in 9 of 110 (8 %) H. influenzae and 21 of 211 (10 %) H. parainfluenzae, respectively. ICEs were not detected among the other Pasteurellaceae. A total of 20 of 60 (33 %) children carried at least 1 oropharyngeal isolate with an ICE possessing all 5 genes. One of the five genes, integrase, however, consisted of two lineages, one of which was highly associated with H. influenzae. The topology of neighbour-joining trees of the remaining four ICE genes was compared and showed a lack of congruence; though, the genes form a common pool among H. influenzae and H. parainfluenzae. This family of antibiotic resistance ICEs was prevalent among the children studied, was genetically diverse, formed a large gene pool, transferred between H. influenzae and H. parainfluenzae, lacked population structure and possessed features suggestive of panmixia, all indicating it has not recently emerged from a single source.
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Iannelli, Francesco, Francesco Santoro, Valeria Fox, and Gianni Pozzi. "A Mating Procedure for Genetic Transfer of Integrative and Conjugative Elements (ICEs) of Streptococci and Enterococci." Methods and Protocols 4, no. 3 (August 28, 2021): 59. http://dx.doi.org/10.3390/mps4030059.
Abstract:
DNA sequencing of whole bacterial genomes has revealed that the entire set of mobile genes (mobilome) represents as much as 25% of the bacterial genome. Despite the huge availability of sequence data, the functional analysis of the mobile genetic elements (MGEs) is rarely reported. Therefore, established laboratory protocols are needed to investigate the biology of this important part of the bacterial genome. Conjugation is a mechanism of horizontal gene transfer which allows the exchange of MGEs among strains of the same or different bacterial species. In streptococci and enterococci, integrative and conjugative elements (ICEs) represent a large part of the mobilome. Here, we describe an efficient and easy-to-perform plate mating protocol for in vitro conjugative transfer of ICEs in streptococci (Streptococcus pneumoniae, Streptococcus agalactiae, Streptococcus gordonii, Streptococcus pyogenes), Enterococcus faecalis, and Bacillus subtilis. Conjugative transfer is carried out on solid media and selection of transconjugants is performed with a multilayer plating. This protocol allows the transfer of large genetic elements with a size up to 81 kb, and a transfer frequency up to 6.7 × 10−3 transconjugants/donor cells.
Dissertations / Theses on the topic "Integrative Conjugative Elements (ICEs)":
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Lao, Julie. "Conception et mise en oeuvre d’une approche bioinformatique dédiée à l’identification des ICE, IME et éléments composites dans les génomes de Firmicutes." Electronic Thesis or Diss., Université de Lorraine, 2021. http://www.theses.fr/2021LORR0063.
Abstract:
Les ICE (Éléments intégratifs conjugatifs) et les IME (Éléments intégratifs mobilisables) sont des éléments mobiles bactériens qui jouent un rôle clé dans les transferts horizontaux. Ils ont la capacité de s'intégrer et de se transférer par conjugaison d'une bactérie à une autre. Ces éléments sont très répandus dans les génomes bactériens mais sont encore mal connus. Leur identification automatique est un défi et ils ne sont en général pas annotés dans les génomes. Jusqu'à présent, seules deux approches bioinformatiques permettent la détection des ICE et la détection des IME, mais leur fiabilité reste très variable, en particulier chez les Firmicutes. De plus, aucune de ces approches ne permet de détecter avec précision les éléments composites constitués d’ICE et d’IME emboîtés ou en accrétions, qui sont fréquemment observés dans des génomes bactériens. Nous avons développé une stratégie et un outil nommé ICEscreen permettant d’identifier les ICE et IME dans les génomes des Firmicutes, y compris les éléments emboîtés ou en accrétions. Notre outil, commence par la détection de quatre protéines signatures (SP) indispensables au fonctionnement de ces éléments puis effectue la détection et le typage des éléments à partir de la colocalisation des SP et de la caractérisation de leur contenu. Notre outil utilise un algorithme dédié permettant de résoudre la structure des éléments qu'ils soient composites ou non. Pour réaliser ces étapes nous avons construit une banque de protéines signatures d’ICE et d’IME de référence à partir d’une liste de gènes connus pour être impliqués dans la dynamique de ces éléments chez les streptocoques ainsi que de profils HMM publics ou construits pour cette étude. Pour valider les résultats d’ICEscreen nous avons construit un jeu de données, FirmiData, constitué de 40 génomes de Firmicutes pour lesquels les ICE et IME ont été annotés semi-manuellement et expertisés. Nous avons ensuite comparé les résultats de ICEscreen avec ceux de deux outils de référence : CONJscan et ICEfinder. ICEscreen détecte la quasi-totalité des éléments de la référence (96 %) ce qui en fait un outil plus performant que CONJscan (58 %) et surtout ICEfinder (53 %) sur notre jeu de données. ICEscreen est ainsi un outil d’aide à l’annotation et à la découverte d’ICE et d’IME dans les génomes de Firmicutes, ce qui peut aider à mieux caractériser leur contribution aux transferts horizontaux de gènes, notamment lors de la transmission de la résistance aux antibiotiques, auxquels ils sont fréquemment associésICEs (Integrative Conjugative Elements) and IMEs (Integrative Mobilizable Elements) are bacterial mobile elements that play a key role in horizontal transfers. They have the capacity to integrate and transfer by conjugation from one bacterium to another. These elements are widespread in bacterial genomes but are still poorly understood. Their automatic identification is a challenge and they are generally not annotated in genomes. So far, only two bioinformatic approaches allow the detection of ICEs and IMEs, but their reliability remains highly variable, particularly among Firmicutes. Moreover, neither of these approaches can accurately detect composite elements consisting of nested or accreted ICEs and IMEs, which are frequently observed in bacterial genomes. We have developed a strategy and a tool called ICEscreen to identify ICEs and IMEs in the genomes of Firmicutes, including nested or accreted elements. Our tool starts with the detection of four signature proteins (SPs) that are essential to the functioning of these elements and then carries out the detection and typing of the elements based on the colocalization of the SPs and the characterisation of their content. Our tool uses a dedicated algorithm to solve the structure of the elements whether they are composite or not. To perform these steps, we have built a bank of ICEs and IMEs signature proteins from a list of genes known to be involved in the dynamics of these elements in streptococci and also public HMM profiles and HMM profiles constructed especially for this study. To validate the ICEscreen results, we built a dataset, FirmiData, consisting of 40 genomes of Firmicutes for which the ICEs and IMEs were annotated semi-manually and curated. We then compared the results of ICEscreen with those of two reference tools: CONJscan and ICEfinder. ICEscreen detects almost all the elements of the reference (96%) making it a more powerful tool than CONJscan (58%) and especially ICEfinder (53%) on our dataset. ICEscreen is thus a tool for the annotation and discovery of ICE and IME in the genomes of Firmicutes, which can help to better characterize their contribution to horizontal gene transfers, particularly during the transmission of antibiotic resistance, with which they are frequently associated
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Coluzzi, Charles. "L'exploration des génomes par l'outil ICEFinder révèle la forte prévalence et l'extrême diversité des ICE et des IME de streptocoques." Thesis, Université de Lorraine, 2017. http://www.theses.fr/2017LORR0352/document.
Abstract:
Les éléments génétiques mobiles contribuent grandement à la diversité et à l’évolution des génomes bactériens par le biais du transfert horizontal. Parmi eux, les éléments intégratifs conjugatifs (ICE) codent leur propre excision, leur transfert par conjugaison et leur intégration. En revanche, les éléments intégratifs et mobilisables (IME) ne sont autonomes que pour leur excision et intégration et ne codent seulement que certaines des protéines/fonctions (oriT) dont ils ont besoin pour leur transfert conjugatif. Par conséquent, les IME ont besoin d’un élément conjugatif « helper » pour se transférer. Malgré leur impact sur le flux des gènes et l’évolution des génomes, la prévalence des ICE reste peu étudiée et seulement très peu d’IME avaient été identifiés au début de cette étude. De plus, bien que plusieurs méthodes de détection des ilots génomiques existent, aucune d’elles n’est dédiée aux ICE ou aux IME. Ce qui ne facilite pas l’analyse exhaustive de ces éléments. Le genre Streptococcus appartient au phylum des firmicutes. La quasi-totalité des streptocoques sont des bactéries commensales ou pathogènes de l’homme et d’autres animaux. Aussi, 2 espèces de streptocoques sont utilisées en tant que ferments lactiques lors la production de laits fermentés et divers fromages. Globalement, le genre streptocoques représente un groupe d’intérêt pour l’homme, l’étude du flux de gènes au sein de ces organismes et l’impact qu’il peut avoir sur leur mode vie est primordiale. Au cours de cette thèse, nous avons recherché les ICE et les IME dans 124 souches de streptocoques appartenant à 27 espèces en utilisant une base de données de référence comportant des protéines dites « signatures » d’IME et d’ICE (de leurs modules de conjugaison/mobilisation et d’integration/excision). Cette analyse exhaustive a permis l’identification et la délimitation de 131 ICE ou ICE légèrement dégénérés et 144 IME. Tous ces éléments ont été délimités, ce qui nous a permis de déterminer leur spécificité d’intégration dans les génomes. Au total, 17 spécificités d’intégration ont été identifiées pour les ICE dont 8 encore jamais décrites (ftsK, guaA, lysS, mutT, rpmG, rpsI, traG and ybaB/EbfC) et 18 spécificités pour les IME dont seulement 5 étaient connues chez les firmicutes. Les modules d’intégration des ICE codent soit une intégrase à tyrosine pouvant avoir une faible spécificité (1 famille d’intégrase) ou une forte spécificité (13 spécificités différentes), soit des intégrases à sérine seule ou en triplet (4 spécificités différentes), soit une transposase à DDE. Les IME codent soit des intégrases à tyrosine (10 spécificités différentes) soit des intégrases à serine seule (8 spécificités différentes). Les ICE ont été groupés en 7 familles distinctes selon les protéines codées par leur module de conjugaison. Les IME présentaient une très forte diversité au sein de leur module de mobilisation, empêchant ainsi leur regroupement en famille selon les gènes portés par ce module. Les analyses phylogénétiques des protéines signature codées par tous les ICE et les IME ont montré des échanges de modules d’intégration entre les ICE et les IME et de nombreux échanges entre les modules de mobilisation des IME. L’ensemble de ces résultats révèle la forte prévalence et l’extrême diversité des ICE et des IME au sein des génomes de streptocoques. Une meilleure connaissance et compréhension de ces éléments nous a incité à construire un outil informatique semi-automatisé de détection des ICE et des IME de Streptocoques ainsi que leurs sites d’insertionMobile genetic elements largely contribute to the evolution and diversity of bacterial genomes through horizontal gene transfer. Among them, the integrative and conjugative elements (ICEs) encode their own excision, conjugative transfer and integration. On the other hand, integrative mobilizable elements (IMEs) are autonomous for excision and integration but encode only some of the proteins needed for their conjugative transfer. IMEs therefore need a “helper” conjugative element to transfer. Despite their impact on gene flow and genome dynamics, the prevalence of ICEs remains largely underscored and very few IMEs were identified at the beginning of this study. Furthermore, although several in silico methods exist to detect genomic islands, none are dedicated to ICEs or IMEs, thus complicating exhaustive examination of these mobile elements. The Streptococcus genus belongs to the firmicutes’ phylum. Almost all streptococci are commensal bacteria or pathogenes to men and animals. Two species of Streptococcus are also used in the dairy industry as lactic ferments in order to produce fermented milk and different types of cheese. Studying the gene flux of the Steptococci genus and the impact it can have on the lifestyle of these organisms is essential, as it has a lot of interest for human health and activities. In this work, we searched for ICEs and IMEs in 124 strains of streptococci belonging to 27 species using a reference database of ICE and IME signature proteins (from their conjugation, mobilization and integration/excision modules). This exhaustive analysis led to the identification and delimitation of 131 ICEs or slightly decayed ICEs and 144 IMEs. All these elements were delimited, which allowed us to identify their integration specificities in the genomes. In total, 17 ICE integration specificities were identified. Among them, 8 had never been described before (ftsK, guaA, lysS, mutT, rpmG, rpsI, traG and ybaB/EbfC). 18 specificities were also identified for IMEs, among which only 5 were known for the firmicutes. ICEs encode high or low-specificity tyrosine integrases (13 different specificities), single serine intégrases (1 specificity), triplet of serine integrases (3 different specificities), or DDE transposases while IMEs encode either tyrosine integrases (10 different specificities) or single serine integrases (8 different specificities). ICE were grouped in 7 distinct families according to the proteins encoded by their conjugation module whereas the mobilization modules of IMEs were highly diverse, preventing them from grouping into families according to their mobilization modules. The phylogenetic analysis of the signature proteins encoded by all ICEs and IMEs showed integration module exchanges between ICEs and IMEs and several mobilization module exchanges between IMEs. The overall results reveal a strong prevalence and extreme diversity of these elements among Streptococci genomes. Better understanding and knowledge of ICEs and IMEs prompted us to build a semi-automated command-line tool to identify streptococcal ICEs and IMEs as well as to determine their insertion site
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Wright, Laurel D. "Autonomous replication of integrative and conjugative elements." Thesis, Massachusetts Institute of Technology, 2016. http://hdl.handle.net/1721.1/106738.
Abstract:
Thesis: Ph. D., Massachusetts Institute of Technology, Department of Biology, 2016.Cataloged from PDF version of thesis.
Includes bibliographical references.
Mobile genetic elements facilitate movement of genes, including those conferring antibiotic resistance and other traits, between bacteria. Integrative and conjugative elements (ICEs), also known as conjugative transposons, are a large family of mobile genetic elements that can transfer between neighboring cells. ICEs are found integrated in the chromosome of their host bacterium, where they are transmitted to daughter cells by chromosomal replication and cell division. Under certain conditions, ICE DNA will excise and form a circular plasmid-like intermediate. It was previously thought that ICEs were incapable of autonomous replication. However, my research, along with the work of others, shows that ICEs can replicate autonomously, and that many ICEs utilize a rolling circle replication mechanism. Plasmids and phages that use rolling circle replication encode a single strand origin (sso) that enhances priming of DNA synthesis. We identified a functional single strand origin, sso1, in the integrative and conjugative element ICEBs1 of Bacillus subtilis. Genetic analyses indicated that ICEBs1 uses sso1 and at least one other region for second strand DNA synthesis. Sso activity was important for autonomous, rolling circle replication of ICEBs1 in host cells, and for stable acquisition of the element in new host cells. I also showed that the broad-host range ICE Tn916 replicates autonomously by a rolling circle mechanism. Replication of Tn916 was dependent on the relaxase encoded by Tn916 orf20. The origin of transfer of Tn916, oriT(916), also functioned as an origin of replication. I found that the relaxase (Orf20) and the two putative helicase processivity factors (Orf22 and Orf23) encoded by Tn916 likely interact in a complex to facilitate replication. Lastly, I identified a functional single strand origin of replication (sso) in Tn916 that I predict primes second strand synthesis during rolling circle replication. The importance of autonomous replication by rolling circle in the ICE lifecycle and horizontal gene transfer processes is discussed.
by Laurel D. Wright.
Ph. D.
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Nouvel, Laurent-Xavier. "Etude de la diversité génétique de Mycoplasma agalactiae : plasticité des génomes, mobilome et dynamique de surface." Thesis, Toulouse, INPT, 2009. http://www.theses.fr/2009INPT013A/document.
Abstract:
Mycoplasma agalactiae est responsable de l'agalactie contagieuse, maladie des petits ruminants difficilement contrôlée et figurant sur la liste de l’OIE. Afin d’évaluer la diversité génétique de ce pathogène, 101 isolats ont été comparés par trois techniques (VNTR, RFLP, répertoire vpma). Les résultats révèlent une grande homogénéité génétique dont la souche type PG2 est représentative. Quelques isolats font exception telle la souche 5632 que nous avons séquencée et analysée ici. La comparaison des génomes et des protéomes entre 5632 et PG2 indiquent que la plasticité de ces génomes est liée à d’importants échanges d'ADN et à la présence de nombreux éléments génétiques mobiles (10% du génome). Ces analyses révèlent également une forte dynamique au sein de répertoires de gènes codant des protéines de surfaces. Pour les mycoplasmes, bactéries minimales dépourvues de paroi, ces évènements ont certainement joués un rôle dans leur survie et leur adaptation à des hôtes complexesMycoplasma agalactiae is responsible of contagious agalactia, a disease of small ruminants that is still difficult to control and is listed by the OIE. In order to evaluate the genetic diversity of this pathogen, 101 isolates were compared using three techniques (VNTR, RFLP, vpma repertoire). Results revealed a high genetic homogeneity with the PG2 type strain as representative. Some isolates however diverged such as the 5632 which was sequenced and analysed here. Whole comparative genomic and proteomic analyses of the 5632 and PG2 strains indicate that their genomic plasticity resides in important genes flux and in the presence of several mobile genetic elements (10% of the genome). These analyses also revealed that specific loci encoding repertoire of surface proteins are highly dynamic. For these minimal bacteria that lack a cell-wall, these events have most likely played a major role in their survival and adaptation to complex hosts
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Haskett, Timothy L. "Discovery and characterisation of tripartite Integrative & Conjugative Elements." Thesis, Haskett, Timothy L. (2018) Discovery and characterisation of tripartite Integrative & Conjugative Elements. PhD thesis, Murdoch University, 2018. https://researchrepository.murdoch.edu.au/id/eprint/41086/.
Abstract:
Bacterial integrative & conjugative elements (ICEs) are chromosomally-integrated DNA islands that excise to form circular molecules capable of horizontal self-transmission via conjugation (cell-to-cell contact). Symbiosis ICEs, such as ICEMlSymR7A of Mesorhizobium loti, are a group of ICEs that carry genes enabling rhizobial bacteria to engage in N2-fixing symbioses with leguminous plants. Transfer of symbiosis ICEs can convert non-symbiotic rhizobia into legume symbionts in a single evolutionary step.
In this thesis, a novel form of “tripartite” ICE (ICE3) is reported that exists as three entirely separated regions of DNA residing in the chromosomes of genetically diverse N2-fixing Mesorhizobium spp. These ICE3 regions did not excise independently, rather through multiple recombinations with the host chromosome they formed a single contiguous region of DNA prior to excision and conjugative transfer. Upon integration into a recipient chromosome, the ICE3 recombined the recipient chromosome to disassemble into the tripartite form. These recombination reactions were catalysed by three Integrase proteins IntG, IntM, and IntS, acting on three associated integrase attachment sites. The “excisive” recombination reactions (i.e. assembly and excision) were stimulated by three recombination directionality factors RdfG, RdfM, and RdfS. Expression of ICE3 transfer and conjugation genes were found to be induced by quorum-sensing. Quorum-sensing activated expression of rdfS, and in turn RdfS stimulated transcription of both rdfG and rdfM. Therefore, RdfS acts as a “master controller” of ICE3 assembly and excision. A model for ICE3 recombination and transfer is presented in this thesis.
The conservation of gene content between symbiosis ICE and ICE3 indicated that these elements share a common evolutionary history. However, the persistence of ICE3 structure in diverse mesorhizobia is perplexing due to its seemingly unnecessary complexity. Bioinformatic comparisons of ICE and ICE3 indicated that the tripartite configuration itself may provide selective benefits to the element, including enhanced host range, host stability and resistance to destabilization by tandem insertion of competing integrative elements.
In congruency with ICEMlSymR7A, ICE3 acquisition can convey upon recipients the ability to form N2-fixing symbiosis with the host-legume of the ICE3 donor. Interestingly, the effectiveness of N2-fixation may be impaired. The consequences of the emergence of sub-optimal N2-fixing strains following ICE3 transfer in agriculture is discussed. If ICE3 transfer poses a barrier for future inoculation success, the elucidation of the mechanism of ICE3 assembly, excision, and transfer will allow for the development of strategies for management.
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Stagg, Georgina. "Creation and characterisation of genetically-marked Mesorhizobium integrative and conjugative elements." Thesis, Stagg, Georgina (2018) Creation and characterisation of genetically-marked Mesorhizobium integrative and conjugative elements. Honours thesis, Murdoch University, 2018. https://researchrepository.murdoch.edu.au/id/eprint/42888/.
Abstract:
Rhizobia are soil-dwelling bacteria capable of forming symbiotic associations with legumes, where they reduce atmospheric dinitrogen (N2) into ammonia (NH3), providing the host plant with a bioavailable nitrogen source. For rhizobia in the genus Mesorhizobium, genes essential to the establishment (nod) and maintenance of nitrogen fixing-legume symbioses (nif and fix) are chromosomally-encoded on mobile segments of DNA known as symbiosis integrative and conjugative elements (ICEs). Symbiosis ICEs are capable of excising from the host chromosome and transferring to a recipient ICE-free cell via bacterial conjugation. In the recipient cell, the invading ICE integrates into the recipient chromosome at conserved sites known as attachment sites. As well as encoding genes for excision, conjugation and integration, symbiosis ICEs often encode genes for vitamin biosynthesis, such as those for the synthesis of nicotinate, biotin and thiamine.
Symbiosis ICEs can be monopartite or tripartite in nature and it appears that these two conformations of elements may be evolutionarily related, with the more complex tripartite ICE hypothesised to have evolved from two recombination reactions between three independent monopartite ancestral ICEs that co-existed in an ancestral bacterial cell. Testing this hypothesis for tripartite ICE evolution requires conjugation experiments between two strains that harbour different symbiosis ICEs, which has not previously been experimentally attempted. Symbiosis ICE transfer studies have been conducted between an ICE donor strain and an ICE-devoid vitamin auxotrophic recipient strain, with ICE transfer exconjugants selected on the basis of vitamin prototrophy. However, this method of selecting exconjugants is ineffective for conjugation experiments between two ICE-harbouring strains, as both usually harbour the operons for nicotinate, biotin and thiamine biosynthesis. Genetically-marking two structurally similar, yet phenotypically distinct monopartite ICEs with a selectable marker, such as an antibiotic resistance gene would allow for screening exconjugants solely on the presence of the selectable marker. Two such ICEs are ICEMcSym1192 from the genome of the Cicer arietinum (chickpea) nodulating microsymbiont Mesorhizobium ciceri CC1192 and ICEMlSymR7A from the genome of the Lotus-nodulating M. loti R7A. Therefore, the aims of this thesis were to first genetically mark the symbiosis ICEs ICEMcSym1192 and ICEMlSymR7A, with antibiotic resistance genes that could facilitate selection of exconjugants in ICE transfer studies. Second, to investigate the free-living growth and symbiotic phenotype of marked symbiosis ICEs. Finally, to test the in vitro mobility of these genetically marked elements.
Using a site-directed mutagenesis approach, M. ciceri CC1192 ICEMcSym1192 was successfully marked within an intergenic region of the symbiosis ICE, with a gene encoding resistance to neomycin/kanamycin (nptII), yielding ICEMcSym1192::nptII. The free-living phenotype of two M. ciceri ICEMcSym1192::nptII derivatives, MCC91 and MCC92, was assessed alongside wild-type CC1192, in a bacterial growth experiment to compare the mean generation times of all three strains cultured in both rich (TY) and minimal (AMS with either glucose or succinate as the sole carbon source) media. Mean generation times were not significantly different between these strains (p > 0.05) in all media tested. Additionally, the symbiotic phenotype of the ICEMcSym1192::nptII derivatives did not differ significantly (p > 0.05) to wild-type CC1192, as measured by mean nodule number, nodule weight and shoot dry weight of inoculated C. arietinum. Using a similar site-directed approach, M. loti R7A ICEMlSymR7A was also marked within an intragenic region, however, with Ω-aadA encoding resistance to spectinomycin/streptomycin, yielding ICEMlSymR7A::Ω-aadA. Two ICEMlSymR7A::Ω-aadA derivatives, MCC93 and MCC94, were completed towards the end of this Honours project, therefore, the free-living and symbiotic phenotype could not be achieved within the scope of this project.
The transfer of ICEMcSym1192::nptII in MCC91 and MCC92, into the ICE-devoid recipient strain, R7ANS, was tested with conjugation mixtures plated onto three different sets of media to select for R7ANS (ICEMcSym1192::nptII) exconjugants. Integration of ICEMcSym1192::nptII in R7ANS should allow exconjugants to be selected solely on the presence of the antibiotic marker conferring neomycin resistance (encoded on ICEMcSym1192::nptII) and tetracycline resistance (encoded on R7ANS plasmid, pFAJ1700). The three selection conditions included rich or minimal media, with reduced tetracycline concentrations and the addition of the vitamin thiamine. While, putative exconjugants were extracted from two selection conditions, PCR screening confirmed these were not R7ANS exconjugants but instead were most likely spontaneous CC1192 tetracycline resistant isolates. The inability to isolate R7ANS (ICEMcSym1192::nptII) exconjugants could be due to a number of reasons, including the use of HEPES-buffered, rather than phosphate-buffered, minimal media, the combination of neomycin and tetracycline in the selection media attenuating the rate of ICE excision and/or transfer or the insertion of the nptII cassette in ICEMcSym1192::nptII affecting ICE mobility. Nevertheless, the marked strains generated in this thesis and the assessment performed on them to date, provides a solid foundation for subsequent experiments to further characterise the mobility of these derivatives.
The discovery that Mesorhizobium symbiosis ICEs can exist in both monopartite and tripartite configurations raises many questions about ICE stability and persistence. The genetically-marked ICEMcSym1192::nptII and ICEMlSymR7A::Ω-aadA produced in this thesis represent an important set of experimental tools necessary to further investigate the evolution of these symbiotic elements.
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Farzand, Robeena. "Occurrence and roles of two integrative and conjugative elements in Klebsiella pneumoniae." Thesis, University of Leicester, 2017. http://hdl.handle.net/2381/40665.
Abstract:
The genome of Klebsiella pneumoniae HS11286 carries two integrative and conjugative elements (ICEs), ICEKpnHS-1 and ICEKpnHS-2; the former belongs to the ICEKp1 family and the latter was unexplored. This study was designed to further characterise the two ICEs, and investigate their prevalence in local clinical K. pneumoniae isolates. Sequence analysis showed that ICEKpnHS-2 belonged to the subfamily of PAPI elements with XerC-like integrases and PCR screening revealed that ICEKpnHS-1 associated elements were more (30%) prevalent in local isolates compared to ICEKpnHS-2 (12.5%). Contributions of these elements to cell physiology, virulence and antibiotic resistance were investigated. Deletion of ICEKpnHS-1 reduced siderophore secretion and growth, particularly in iron restricted conditions. The ΔICEKpnHS-1 strain also showed reduced resistance to various antibiotics, especially those known to be affected by the ATP binding cassette (ABC) and major facilitator superfamily (MFS) exporters. Assays in Galleria mellonella provided preliminary evidence that deletion of ICEKpnHS-2 reduced the virulence of K. pneumoniae HS11286. Type IV secretion systems (T4SS) are major component modules of ICEs responsible for conjugative transfer of nucleoprotein complexes. Observed reduction of conjugative transfer of one of the ICEs following deletion of the other led us to study interactions between the two distinct T4SSs encoded on the ICEs in HS11286. A marker plasmid containing oriT of ICEKpnHS-1 (P-oriT1) was constructed and deletion of ICEKpnHS-2 was shown to produce a six–fold reduction in trans-conjugants. Deletion of the mobB (ICEKpnHS-1) orthologue in ICEKpnHS-2 (mob-2) and traI (relaxase of ICEKpnHS-2) both produced similar defects in transconjugants frequencies that could be complemented in-trans. The ATPase Mob-1 was bioinformatically shown to lack a Walker B and it was speculated that Mob-2 might compensate for this. Accordingly, point mutations in Walker motifs of mob-2 provided evidence supporting this complementary function in energy transduction contributing significantly to the crosstalk between the two non-homologous ICEs. Data on frequency of transfer of the native chromosomal ICEKpnHS-1 and its effects on the phenotypes of an E. coli were also shown. However, ICEKpnHS-2 self-conjugation was not detected.
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fox, Valeria. "Mobile genetic elements carrying stress response systems, antibiotic resistance determinants, and catabolic pathways." Doctoral thesis, Università di Siena, 2021. http://hdl.handle.net/11365/1159250.
Abstract:
In the present thesis, I studied the activation of an SOS-like response in Streptococcus pneumoniae encoded by the Streptococcus pyogenes prophage φ1207.3. This system leads to the temporary activation of an hypermutable phenotype, which resulted in increased survival and increased mutation rate upon exposure to mitomycin C or UV-C light. Then, a different type of stress response, the Envelope Stress Response (ESR), was exploited as a strategy for sensitization of Escherichia coli to several antibiotics, by disbalancing five pathways, namely σE, Cpx, Rcs, Bae, and Psp. Disbalancing the Psp pathway increased E. coli susceptibility to some beta-lactam antibiotics. Prophage φ1207.3, carrying a two-genes macrolide efflux system, was originally described as an Integrative and Conjugative Element (ICE). In this thesis, φ1207.3 was transferred to the standard pneumococcal laboratory strain Rx1, for which the whole genome sequence was obtained. It was demonstrated that φ1207.3 is a functional phage of the Siphoviridae family, able to form mature phage particles. It was shown that φ1207.3 does not enter the lytic cycle, even upon induction with mitomycin C. Since φ1207.3 transfers through a mechanism requiring cell-to-cell contact resembling conjugation, the cellular localization of φ1207.3 was investigated. It was demonstrated that the number of φ1207.3 phage particles on the bacterial cells exceeds the number of phages in the culture supernatant by 3 orders of magnitude. φ1207.3 transfer to a variety of streptococcal species was obtained by setting up a mating protocol for the transfer of large mobile genetic elements. Tn5253 is a composite ICE of Streptococcus pneumoniae carrying two elements: i) the ICE Tn5251, carrying the tet(M) tetracycline resistance gene, and ii) the Ωcat(pC194) not-conjugative element, harbouring the cat chloramphenicol resistance gene and able of intracellular transposition. The Tn5253 chromosomal integration site (attB) was investigated in S. pneumoniae with different backgrounds and in other streptococcal and enterococcal species. Finally, during the sequencing of two Mycobacterium chimaera strains, it was reported the presence of an ICE carrying putative genes involved in the catabolic degradation of polycyclic aromatic hydrocarbons, important environmental pollutants.
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Laroussi, Haifa. "Étude des mécanismes moléculaires d'initiation du transfert conjugatif d'ICESt3, médiée par une relaxase MOBT chez la bactérie Gram+ Streptococcus thermophilus." Electronic Thesis or Diss., Université de Lorraine, 2022. http://www.theses.fr/2022LORR0176.
Abstract:
Les génomes bactériens évoluent principalement grâce au transfert horizontal de gènes. La conjugaison bactérienne en est un des mécanismes majeurs. Elle est notamment médiée par les éléments intégratifs et conjugatifs (ICE). En plus de leur transfert, les ICE codent d'autres fonctions conférant à leur hôte un avantage adaptatif, comme par exemple des résistances aux antibiotiques dont la diffusion est un enjeu majeur en santé publique. Il est donc nécessaire de comprendre comment les ICE se transfèrent si l'on veut limiter leur dissémination. Le transfert d'un ICE d'une cellule donatrice vers une cellule réceptrice implique son excision du chromosome, son transfert puis son intégration dans les génomes des deux cellules partenaires. Les données de la littérature révèlent que l'initiation de ce transfert est médiée par un complexe nucléoprotéique appelé relaxosome, dont la protéine clé est la relaxase, une transestérase codée par l'élément. Le rôle de la relaxase est d'effectuer une coupure simple brin sur l'ADN de l'ICE au niveau d'un site conservé, appelé nic. Ce clivage libère une extrémité 3'OH libre, servant d'amorce pour initier la réplication en cercle roulant. Le complexe ADN-relaxase est alors dirigé vers le pore de conjugaison. Au cours de ma thèse j'ai étudié un ICE modèle, ICESt3 de Streptococcus thermophilus qui appartient à la superfamille ICESt3/Tn916/ICEBs1, très répandue chez les Firmicutes. Ces ICE possèdent une relaxase non canonique, appartenant à la famille MOBT, apparentée aux initiateurs de réplication à cercle roulant de la famille Rep_trans. L'objectif de ma thèse était d'élucider le fonctionnement de la relaxase RelSt3 afin de décrypter les mécanismes moléculaires d'initiation du transfert conjugatif médié par une relaxase MOBT. Mes recherches ont conduit à l'identification du site de liaison de RelSt3 sur l'origine de transfert (oriT) d'ICESt3. Ce site, appelé bind, a pour originalité d'être distant du site nic, ce qui n'est pas le cas des autres familles de relaxases. RelSt3 présente un domaine HTH à son extrémité N-terminal. J'ai montré que ce domaine est requis pour la fixation de RelSt3 sur le site bind, et important pour son activité catalytique. Des tests de conjugaison ont démontré que ce domaine HTH est crucial pour le transfert conjugatif d'ICESt3. Des prédictions structurales de ce domaine en complexe avec l'ADN ont conduit à l'identification de l'interface d'interaction avec le site bind, confirmée par mutagénèse dirigée. J'ai également démontré que RelSt3 présente une activité de coupure-religature et qu'elle se fixe de façon covalente sur l'extrémité 5' du brin clivé, démontrant ainsi que cette enzyme participe aux étapes initiale et terminale de la conjugaison. Dans la littérature, il a été démontré que les relaxases interagissent fréquemment avec d'autres protéines accessoires, codées par l'ICE ou la bactérie hôte pour former le relaxosome. Le deuxième objectif de ma thèse était d'identifier des partenaires de RelSt3. L'analogie avec ICEBs1 chez Bacillus subtilis a permis d'identifier deux protéines candidates OrfL et OrfM codées par ICESt3, ainsi qu'une hélicase cellulaire, probablement impliquée dans la réplication en cercle roulant, nommée PcrA. Une caractérisation de ces protéines candidates a été effectuée en utilisant des approches biochimiques et biophysiques. Le réseau d'interaction entre l'ensemble de ces protéines a été dressé en utilisant des approches in vitro, ainsi que l'approche double hybride in vivo. Ces données nous permettent d'avoir un premier aperçu des constituants du relaxasome d'ICESt3. J'ai par ailleurs montré que OrfL et OrfM stimulent l'activité catalytique de RelSt3 in vitro, et qu'elles sont toutes les deux essentielles à la conjugaison d'ICESt3.Ce travail nous apporte une meilleure compréhension des mécanismes moléculaires en jeu lors de la conjugaison d'un ICE pilotée par une relaxase de la famille MOBTBacterial genomes evolve mainly through horizontal gene transfer. Bacterial conjugation is one of the major mechanisms for these transfers. Conjugation is mediated by integrative and conjugative elements (ICE). In addition to their transfer function, ICEs encode other functions that may provide an adaptive advantage to their host, such as resistance to antibiotics whose dissemination is a major public health issue. It is therefore necessary to understand how ICEs are transferred in order to limit their dissemination.The transfer of an ICE from a donor cell to a recipient cell requires its excision from the chromosome, its transfer from one cell to the other and then its integration into the genomes of the two partner cells. According to the literature, the initiation of ICE transfer is mediated by a nucleoprotein complex called relaxosome, whose key protein is the relaxase, a transesterase encoded by the element. The role of the relaxase is to perform a single-stranded cleavage on the DNA of the ICE at a conserved site, called nic. This cleavage releases a free 3'OH end, used as a primer to initiate rolling circle replication. The DNA-relaxase complex is then driven to the conjugation pore.During my PhD thesis, I studied ICESt3 from Streptococcus thermophilus which belongs to the ICESt3/Tn916/ICEBs1 superfamily, widespread among Firmicutes. These ICEs encode a non-canonical relaxase belonging to the MOBT family, which is related to the rolling circle replication initiators of the Rep_trans family. The general objective of my thesis was to elucidate the function of the RelSt3 relaxase in order to decipher the molecular mechanisms of initiation of conjugative transfer mediated by a MOBT relaxase.My work led to the identification of the RelSt3 binding site on ICESt3 origin of transfer (oriT). This site, called bind, is peculiar in that it is distant from the nic site, which is not the case for other relaxase families. RelSt3 possesses an HTH domain at its N-terminus. I have shown that this domain is required for the binding of RelSt3 to its bind site, and that it is important for its catalytic activity. Conjugation assays demonstrated that this HTH domain is crucial for the conjugative transfer of ICESt3. Structural predictions of the HTH domain in complex with DNA led to the identification of the interaction interface with the bind site, confirmed by mutagenesis. I also demonstrated that RelSt3 exhibits a nicking-closing activity and that it covalently binds to the 5' end of the cleaved strand, demonstrating that this enzyme participates in both initial and final steps of conjugation.In the literature, it has been shown that relaxases interact frequently with other accessory proteins, encoded by the ICE or by the host bacteria, participating in relaxosome formation. The second objective of my thesis was to identify RelSt3 partners. Comparisons with available data on ICEBs1 from Bacillus subtilis allowed to identify two candidate proteins, OrfL and OrfM, that may belong to the relaxosome of ICESt3, as well as a cellular helicase, PcrA , probably involved in the rolling circle replication. A characterization of these proteins was performed using biochemical and biophysical approaches. The interaction network between all of these proteins was established using in vitro approaches, as well as with the in vivo two-hybrid approach. These data provide a first insight into the components of the ICESt3 relaxasome. I also showed that OrfL and OrfM stimulate the catalytic activity of RelSt3 in vitro, and that they are both essential for ICESt3 conjugation.This work lead to a better understanding of the molecular mechanisms required during the conjugation of an ICE driven by a MOBT family relaxase
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SPAGNOLETTI, MATTEO. "Comparative genomics of V. cholerae 7th pandemic strains. Analysis of integrative conjugative elements, genomic islands and prophages." Doctoral thesis, 2012. http://hdl.handle.net/11573/917386.
Book chapters on the topic "Integrative Conjugative Elements (ICEs)":
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Cury, Jean, Sophie S. Abby, Olivia Doppelt-Azeroual, Bertrand Néron, and Eduardo P. C. Rocha. "Identifying Conjugative Plasmids and Integrative Conjugative Elements with CONJscan." In Horizontal Gene Transfer, 265–83. New York, NY: Springer US, 2019. http://dx.doi.org/10.1007/978-1-4939-9877-7_19.
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Cunha, Violette Da, Romain Guérillot, Mathieu Brochet, and Philippe Glaser. "Integrative and Conjugative Elements Encoding DDE Transposases." In Bacterial Integrative Mobile Genetic Elements, 250–60. Boca Raton: CRC Press, 2022. http://dx.doi.org/10.1201/9780367813925-15.
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Ciric, Lena, Azmiza Jasni, Lisbeth Elvira de Vries, Yvonne Agersø, Peter Mullany, and Adam P. Roberts. "The Tn916/Tn1545 Family of Conjugative Transposons." In Bacterial Integrative Mobile Genetic Elements, 153–70. Boca Raton: CRC Press, 2022. http://dx.doi.org/10.1201/9780367813925-9.
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Garriss, Geneviéve, and Vincent Burrus. "Integrating Conjugative Elements of the SXT/R391 Family." In Bacterial Integrative Mobile Genetic Elements, 217–34. Boca Raton: CRC Press, 2022. http://dx.doi.org/10.1201/9780367813925-13.
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Salyers, Abigail A., Jeffrey F. Gardner, and Nadja B. Shoemaker. "Excision and Transfer of Bacteroides Conjugative Integrated Elements." In Bacterial Integrative Mobile Genetic Elements, 235–49. Boca Raton: CRC Press, 2022. http://dx.doi.org/10.1201/9780367813925-14.
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Berkmen, Melanie B., Stephanie J. Laurer, Bridget K. Giarusso, and Rodrigo Romero. "The Integrative and Conjugative Element ICEBs1 of Bacillus subtilis." In Bacterial Integrative Mobile Genetic Elements, 201–16. Boca Raton: CRC Press, 2022. http://dx.doi.org/10.1201/9780367813925-12.
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Esnault, Emilie, Alain Raynal, and Jean-Luc Pernodet. "pSAM2, a Paradigm for a Family of Actinomycete Integrative and Conjugative Elements." In Bacterial Integrative Mobile Genetic Elements, 135–52. Boca Raton: CRC Press, 2022. http://dx.doi.org/10.1201/9780367813925-8.
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A., Minimol V., Pankaj Kishore, and Mukteswar Prasad Mothadaka. "Evolution and the Role of SXT-Related Integrative Conjugative Elements in Multidrug-Resistant Vibrio cholerae." In Handbook on Antimicrobial Resistance, 1–17. Singapore: Springer Nature Singapore, 2023. http://dx.doi.org/10.1007/978-981-16-9723-4_22-1.
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Minimol, V. A., Pankaj Kishore, and Mukteswar Prasad Mothadaka. "Evolution and the Role of SXT-Related Integrative Conjugative Elements in Multidrug-Resistant Vibrio cholerae." In Handbook on Antimicrobial Resistance, 465–81. Singapore: Springer Nature Singapore, 2023. http://dx.doi.org/10.1007/978-981-19-9279-7_22.
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Armshaw, Patricia, and J. Tony Pembroke. "UV Stress-Responsive Genes Associated with Enterobacterial Integrative Conjugative Elements of the ICE SXT/R391 Group." In Stress and Environmental Regulation of Gene Expression and Adaptation in Bacteria, 517–27. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2016. http://dx.doi.org/10.1002/9781119004813.ch48.