Elusive marine nitrogen fixation

Nitrogen Fixation Among Marine Bacterioplankton

Nitrogen Fixation in Denitrified Marine Waters

Nitrogen fixation is an essential process that biologically transforms atmospheric dinitrogen gas to ammonia, therefore compensating for nitrogen losses occurring via denitrification and anammox. Currently, inputs and losses of nitrogen to the ocean resulting from these processes are thought to be spatially separated: nitrogen fixation takes place primarily in open ocean environments (mainly th...

Chasing after Non-cyanobacterial Nitrogen Fixation in Marine Pelagic Environments

Traditionally, cyanobacterial activity in oceanic photic layers was considered responsible for the marine pelagic dinitrogen (N2) fixation. Other potentially N2-fixing bacteria and archaea have also been detected in the pelagic water column, however, the activity and importance of these non-cyanobacterial diazotrophs (NCDs) remain poorly constrained. In this perspective we summarize the N2 fixa...

Process-understanding of marine nitrogen fixation under global change

In view of the current increase in atmospheric pCO2 and concomitant changes in the marine environment, it is crucial to assess, understand, and predict future responses of ecologically relevant phytoplankton species. The diazotrophic cyanobacterium Trichodesmium erythraeum was found to respond strongly to elevated pCO2 by increasing growth, production rates, and N2 fixation. The magnitude of th...

Trichodesmium – a widespread marine cyanobacterium with unusual nitrogen fixation properties

The last several decades have witnessed dramatic advances in unfolding the diversity and commonality of oceanic diazotrophs and their N2 -fixing potential. More recently, substantial progress in diazotrophic cell biology has provided a wealth of information on processes and mechanisms involved. The substantial contribution by the diazotrophic cyanobacterial genus Trichodesmium to the nitrogen i...