Abstract Quantitative PCR (Q-PCR or real-time PCR) approaches are now widely applied in
microbial ecology to quantify the abundance and expression of taxonomic and functional …

Biological N2 fixation is an important part of the marine nitrogen cycle as it provides a source
of new nitrogen that can support biological carbon export and sequestration. Research in …

Marine diazotrophs convert dinitrogen (N 2) gas into bioavailable nitrogen (N), supporting
life in the global ocean. In 2012, the first version of the global oceanic diazotroph database …

Nitrogen fixation in the surface ocean impacts global marine nitrogen bioavailability and
thus microbial primary productivity. Until now, cyanobacterial populations have been viewed …

Symbioses between nitrogen (N) 2–fixing prokaryotes and photosynthetic eukaryotes are
important for nitrogen acquisition in N-limited environments. Recently, a widely distributed …

Marine N 2 fixing microorganisms, termed diazotrophs, are a key functional group in marine
pelagic ecosystems. The biological fixation of dinitrogen (N 2) to bioavailable nitrogen …

Abstract Microbial dinitrogen (N 2) fixation, the nitrogenase enzyme-catalysed reduction of N
2 gas into biologically available ammonia, is the main source of new nitrogen (N) in the …

The marine nitrogen (N) cycle controls the productivity of the oceans. This cycle is driven by
complex biogeochemical transformations, including nitrogen fixation, denitrification, and …

The two commonly applied methods to assess dinitrogen (N2) fixation rates are the 15N2-
tracer addition and the acetylene reduction assay (ARA). Discrepancies between the two …

Nitrogen fixation is critical for the biological productivity of the ocean, but clear mechanistic
controls on this process remain elusive. Here, we investigate the abundance, activity, and …