Cell-specific measurements show nitrogen fixation by particle-attached putative non-cyanobacterial diazotrophs in the North Pacific Subtropical Gyre

Abstract

Nitrogen-fixing (diazotrophic) cyanobacteria provide a critical nutrient input to the ocean. Non-cyanobacterial diazotrophs are also thought to contribute, but they have not been observed to fix nitrogen. Using dual isotope labeling combined with nanoscale secondary ion mass spectrometry, this study demonstrates that putative non-cyanobacterial diazotrophs attached to particles can fix nitrogen.