Prokaryotic communities across oceanic depths produce stable dissolved organic nitrogen

mechanisms could produce long-lived DON, including through microbial production and reprocessing of organic matter, a microbial N pump.However, it is not clear whether long-lived DON is produced equally across all water depths.In this study, we provide evidence that microbes from all oceanic depths can produce this stable material, but this production is likely more important in the surface ocean where microbes encounter more bioavailable organic matter.