Unveiling the contribution of particle-associated non-cyanobacterial diazotrophs to N fixation in the upper mesopelagic North Pacific Gyre.

Dinitrogen (N) fixation supports marine life through the supply of reactive nitrogen. Recent studies suggest that particle-associated non-cyanobacterial diazotrophs (NCDs) could contribute significantly to N fixation contrary to the paradigm of diazotrophy as primarily driven by cyanobacterial genera. We examine the community composition of NCDs associated with suspended, slow, and fast-sinking particles in the North Pacific Subtropical Gyre.