{"database":"biostudies-literature","file_versions":[],"scores":null,"additional":{"omics_type":["Unknown"],"volume":["14"],"submitter":["Wongdee J"],"pubmed_abstract":["RpoN is an alternative sigma factor (sigma 54) that recruits the core RNA polymerase to promoters of genes. In bacteria, RpoN has diverse physiological functions. In rhizobia, RpoN plays a key role in the transcription of nitrogen fixation (<i>nif</i>) genes. The <i>Bradyrhizobium</i> sp. DOA9 strain contains a chromosomal (c) and plasmid (p) encoded RpoN protein. We used single and double <i>rpoN</i> mutants and reporter strains to investigate the role of the two RpoN proteins under free-living and symbiotic conditions. We observed that the inactivation of <i>rpoNc</i> or <i>rpoNp</i> severely impacts the physiology of the bacteria under free-living conditions, such as the bacterial motility, carbon and nitrogen utilization profiles, exopolysaccharide (EPS) production, and biofilm formation. However, free-living nitrogen fixation appears to be under the primary control of RpoNc. Interestingly, drastic effects of <i>rpoNc</i> and <i>rpoNp</i> mutations were also observed during symbiosis with <i>Aeschynomene americana</i>. Indeed, inoculation with <i>rpoNp</i>, <i>rpoNc</i>, and double <i>rpoN</i> mutant strains resulted in decreases of 39, 64, and 82% in the number of nodules, respectively, as well as a reduction in nitrogen fixation efficiency and a loss of the bacterium's ability to survive intracellularly. Taken together, the results show that the chromosomal and plasmid encoded RpoN proteins in the DOA9 strain both play a pleiotropic role during free-living and symbiotic states."],"journal":["Frontiers in microbiology"],"pagination":["1131860"],"full_dataset_link":["https://www.ebi.ac.uk/biostudies/studies/S-EPMC9977809"],"repository":["biostudies-literature"],"pubmed_title":["Role of two RpoN in <i>Bradyrhizobium</i> sp. strain DOA9 in symbiosis and free-living growth."],"pmcid":["PMC9977809"],"pubmed_authors":["Boonkerd N","Songwattana P","Giraud E","Piromyou P","Wongdee J","Nouwen N","Greetatorn T","Teaumroong N","Tittabutr P"],"additional_accession":[]},"is_claimable":false,"name":"Role of two RpoN in <i>Bradyrhizobium</i> sp. strain DOA9 in symbiosis and free-living growth.","description":"RpoN is an alternative sigma factor (sigma 54) that recruits the core RNA polymerase to promoters of genes. In bacteria, RpoN has diverse physiological functions. In rhizobia, RpoN plays a key role in the transcription of nitrogen fixation (<i>nif</i>) genes. The <i>Bradyrhizobium</i> sp. DOA9 strain contains a chromosomal (c) and plasmid (p) encoded RpoN protein. We used single and double <i>rpoN</i> mutants and reporter strains to investigate the role of the two RpoN proteins under free-living and symbiotic conditions. We observed that the inactivation of <i>rpoNc</i> or <i>rpoNp</i> severely impacts the physiology of the bacteria under free-living conditions, such as the bacterial motility, carbon and nitrogen utilization profiles, exopolysaccharide (EPS) production, and biofilm formation. However, free-living nitrogen fixation appears to be under the primary control of RpoNc. Interestingly, drastic effects of <i>rpoNc</i> and <i>rpoNp</i> mutations were also observed during symbiosis with <i>Aeschynomene americana</i>. Indeed, inoculation with <i>rpoNp</i>, <i>rpoNc</i>, and double <i>rpoN</i> mutant strains resulted in decreases of 39, 64, and 82% in the number of nodules, respectively, as well as a reduction in nitrogen fixation efficiency and a loss of the bacterium's ability to survive intracellularly. Taken together, the results show that the chromosomal and plasmid encoded RpoN proteins in the DOA9 strain both play a pleiotropic role during free-living and symbiotic states.","dates":{"release":"2023-01-01T00:00:00Z","publication":"2023","modification":"2024-11-20T12:07:17.772Z","creation":"2024-11-20T12:07:17.772Z"},"accession":"S-EPMC9977809","cross_references":{"pubmed":["36876109"],"doi":["10.3389/fmicb.2023.1131860"]}}