Cyanate – a low abundant but actively cycled nitrogen compound in soil

Abstract

Cyanate (NCO-) can serve as a nitrogen and/or carbon source for different microorganisms and even additionally as an energy source for autotrophic ammonia oxidizers. Despite the widely distributed genetic potential for direct cyanate utilization among bacteria, archaea and fungi, the availability and environmental significance of cyanate is largely unknown, especially in terrestrial ecosystems. We found relatively low concentrations of soil cyanate, but its turnover was rapid. Contrary to our expectations, cyanate consumption was clearly dominated by biotic processes, and, notably, cyanate was produced in-situ at rates similar to that of cyanate formation from urea fertilizer, which is believed to be one of the major sources of cyanate in the environment. Our study provides evidence that cyanate is actively turned over in soils and represents a small but continuous nitrogen/energy source for soil microbes, potentially contributing to a selective advantage of microorganisms capable of direct cyanate utilization.

Positron‐emitting radiotracers spatially resolve unexpected biogeochemical relationships linked with methane oxidation in Arctic soils

“…The gene coding for cyanate lyase was also enriched in [ 11 C]CH 4 uptake hotspots. Cyanate lyase catalyses cyanate transformation to carbamate, which may convert to NH 3 and CO 2 (Johnson & Anderson, 1987; Mooshammer et al, 2021). While this may be an important NH 3 source for microorganisms, low concentrations of cyanate (≈pmol g −1 soil) and its transient nature (Mooshammer et al, 2021) preclude use of N‐XANES for identification in soils.…”

“…Several CH 4 metabolism-related genes detected within R. (Johnson & Anderson, 1987;Mooshammer et al, 2021). While this may be an important NH 3 source for microorganisms, low concentrations of cyanate (≈pmol g −1 soil) and its transient nature (Mooshammer et al, 2021) preclude use of N-XANES for identification in soils. N-limited environments (Bodelier & Laanbroek, 2004;Mohanty et al, 2006).…”

Unraveling sources of cyanate in the marine environment: insights from cyanate distributions and production during the photochemical degradation of dissolved organic matter

“…Previous studies primarily addressed cyanate utilization, the sources of cyanate largely unknown (Kitzinger et al, 2019;Linder, 2019;Saéz et al, 2019;Mooshammer et al, 2021). The results of this study reveal that cyanate can be produced by photochemical degradation of DOM in diverse environments.…”

“…Cyanate also serves as an organic nitrogen source in both terrestrial and marine environments. It is recently found that cyanate serves as an active nitrogen or energy source for soil microbes (Mooshammer et al, 2021). The discovery of the cyanase gene in various marine microbes, particularly in the picocyanobacterial strains, such as Synechococcus sp.…”