Oxygen-tolerant nitrogen fixation in a marine alga-colonizing <i>Planctomycetota</i>.

ABSTRACT: The microbiomes colonizing macroalgal surfaces orchestrate nutrient fluxes and symbiotic interactions within the algal environment. Among these communities, Planctomycetota are often dominant taxa. Although nitrogenase (nif) gene clusters have been identified in Planctomycetota isolates and metagenome-assembled genomes, functional validation of nitrogen fixation in pure culture has remained elusive. Moreover, the mechanisms enabling these bacteria to overcome oxygen sensitivity and fix nitrogen in algal-associated oxic niches remain unexplored. Here, we isolated Crateriforma sp. HD03, a Planctomycetota strain from the surface of Saccharina japonica (kelp), and provided the first experimental evidence of nitrogen-fixing activity in pure-cultured

SUBMITTER: Zhang Z 

PROVIDER: S-EPMC12628686 | biostudies-literature | 2025 Nov

REPOSITORIES: biostudies-literature