Publicação
A catalogue of the prophages of the genus Helicobacter
| Resumo: | The genus Helicobacter comprises species that colonize the gastric mucosa (gastric Helicobacter, like Helicobacter pylori) and the liver/intestinal tracts (enterohepatic Helicobacter) of distinct classes of the subphylum Vertebrata. Complete H. pylori prophages showed that prophage genes tend to belong to the host’s phylogeographic group, reinforcing co-evolution. However, this scenario between prophages and host bacteria within the genus Helicobacter remains undetermined. This thesis’ main goal is to analyze and identify prophage elementsin Helicobacter species and comprehend the co-evolutionary scenario between prophages and their hosts. A collection of 343 genomes from non-pylori Helicobacter was analyzed. A total of 119 complete prophages were found and analyzed, scoping their genome characteristics and families. There were 457 orthologous genes found in all complete prophages, with higher number of orthologous genes observed in enterohepatic prophages compared to gastric ones, mirroring the same trend in their respective bacterial hosts. In the phylogenetic tree of all complete prophages, Hpametensis1288_1, Hjaachi09_6949, and H. canis prophages didn’t follow the cluster division segregating gastric and enterohepatic species, typically found among Helicobacter species. This difference was also evident by shared genes network analysis and gene synteny. The phylogenetic congruence between the trees of bacteria and prophages evidenced a general dependence of the phage phylogeny on the host’s phylogeny, even with some individual pairs not contributing to these results. These divergence results were found within gastric or enterohepatic groups, depicting a distinct evolutionary history at a narrower level. Overall, the Helicobacter prophages seem to have a co-evolution with their hosts, with high synteny, and the gastric prophages appear to have a higher diversity, although some exceptions arise. This study introduces a novel set of prophage sequences associated with non-pylori Helicobacter species, serving as valuable foundation for exploring prophages within the Helicobacter genus, and offering comprehensive insights into their presence and co-evolutionary history. |
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| Autores principais: | Proença, Marta Sousa |
| Assunto: | Co-evolução filogenia Helicobacter profago Teses de mestrado - 2023 |
| Ano: | 2023 |
| País: | Portugal |
| Tipo de documento: | dissertação de mestrado |
| Tipo de acesso: | acesso embargado |
| Instituição associada: | Universidade de Lisboa |
| Idioma: | inglês |
| Origem: | Repositório da Universidade de Lisboa |
| Resumo: | The genus Helicobacter comprises species that colonize the gastric mucosa (gastric Helicobacter, like Helicobacter pylori) and the liver/intestinal tracts (enterohepatic Helicobacter) of distinct classes of the subphylum Vertebrata. Complete H. pylori prophages showed that prophage genes tend to belong to the host’s phylogeographic group, reinforcing co-evolution. However, this scenario between prophages and host bacteria within the genus Helicobacter remains undetermined. This thesis’ main goal is to analyze and identify prophage elementsin Helicobacter species and comprehend the co-evolutionary scenario between prophages and their hosts. A collection of 343 genomes from non-pylori Helicobacter was analyzed. A total of 119 complete prophages were found and analyzed, scoping their genome characteristics and families. There were 457 orthologous genes found in all complete prophages, with higher number of orthologous genes observed in enterohepatic prophages compared to gastric ones, mirroring the same trend in their respective bacterial hosts. In the phylogenetic tree of all complete prophages, Hpametensis1288_1, Hjaachi09_6949, and H. canis prophages didn’t follow the cluster division segregating gastric and enterohepatic species, typically found among Helicobacter species. This difference was also evident by shared genes network analysis and gene synteny. The phylogenetic congruence between the trees of bacteria and prophages evidenced a general dependence of the phage phylogeny on the host’s phylogeny, even with some individual pairs not contributing to these results. These divergence results were found within gastric or enterohepatic groups, depicting a distinct evolutionary history at a narrower level. Overall, the Helicobacter prophages seem to have a co-evolution with their hosts, with high synteny, and the gastric prophages appear to have a higher diversity, although some exceptions arise. This study introduces a novel set of prophage sequences associated with non-pylori Helicobacter species, serving as valuable foundation for exploring prophages within the Helicobacter genus, and offering comprehensive insights into their presence and co-evolutionary history. |
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