Diversity of dirammox microorganisms.

Dirammox genes are present in 690 genomes across 3 phyla and 26 genera, with nearly ubiquitous occurrence in Alcaligenes, Delftia, and Microvirgula.

• Why it matters: Understanding the diversity and distribution of dirammox microorganisms is crucial because it may reveal an overlooked pathway of nitrogen transformation in organic-rich habitats, expanding current knowledge of the nitrogen cycle.
• What they did: Large-scale genome mining identified complete dnfABC gene clusters, analyzed their phylogeny and organization, and tested their activity in Escherichia coli, revealing broad distribution and metabolic potential.
• The result: Dirammox is a widespread, metabolically flexible pathway that may significantly contribute to nitrogen cycling, especially under conditions where other nitrogen transformations are limited.