The dinitrogenase reductase gene (nifH) is the most widely established molecular marker for the study of nitrogen-fixing prokaryotes in nature. A large number of PCR primer sets have been developed for nifH amplification, and the effective deployment …
The global diversity of nitrogen-fixing microorganisms was assessed through construction and analysis of an aligned database of 16,989 nifH sequences. We conclude that the diversity of diazotrophs is still poorly described and that many organisms …