Potential evolutionary impact of integrative and conjugative elements (ICEs) and genomic islands in the Ralstonia solanacearum species complex

• Published in: Scientific reports Vol. 10; no. 1; p. 12498
• Main Authors: Gonçalves, Osiel Silva, de Queiroz, Marisa Vieira, Santana, Mateus Ferreira
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 27-07-2020; Nature Publishing Group
• Subjects: 631/208/212/2304; 631/208/212/2305; Biological Evolution; Conjugation, Genetic - genetics; Genome, Bacterial; Genomes; Genomic islands; Genomic Islands - genetics; Humanities and Social Sciences; Islands; Likelihood Functions; multidisciplinary; Open Reading Frames - genetics; Pathogenicity; Pathogens; Phylogeny; Ralstonia solanacearum; Ralstonia solanacearum - genetics; Science; Science (multidisciplinary); Species
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-020-69490-1

Ralstonia solanacearum
, a soil-borne plant pathogen, encompasses a large number of strains known as
R. solanacearum
species complex (RSSC). Although it has been suggested that mobile genetic elements (MGEs) may play an important role in the RSSC genome, the evolutionary impact of these elements remains unknown. Here, we identified and analysed Integrative and Conjugative Elements (ICEs) and Genomic Islands (GIs) in the 121 genomes published for
Ralstonia
spp., including RSSC strains and three other non-plant pathogenic
Ralstonia
spp. Our results provided a dataset of 12 ICEs and 31 GIs distributed throughout
Ralstonia
spp. Four novel ICEs in RSSC were found. Some of these elements cover 5% of the host genome and carry accessory genes with a potential impact on the fitness and pathogenicity of RSSC. In addition, phylogenetic analysis revealed that these MGEs clustered to the same species, but there is evidence of strains from different countries that host the same element. Our results provide novel insight into the RSSC adaptation, opening new paths to a better understanding of how these elements affect this soil-borne plant pathogen.