From: Treseder KK, Lennon JT. 2015. Fungal traits that drive ecosystem dynamics on land. Microbiology and Molecular Biology Reviews 79:243-262.
Where O2 is absent or minimal, certain fungi can denitrify nitrate or nitrite, resulting in the production of N2O (Shoun et al. 2012). Denitrification is important because N2O is a particularly effective greenhouse gas, and because denitrification is a pathway of N loss from ecosystems (Chapin et al. 2011). Before the 1990s, fungi were not widely recognized as major contributors to denitrification in natural ecosystems (Shoun and Tanimoto 1991, Shoun et al. 1992, Shoun et al. 2012). Nonetheless, terrestrial field studies have suggested that fungal denitrification can indeed represent a significant ecosystem flux (Laughlin and Stevens 2002, Wallenstein et al. 2006, Herold et al. 2012, Marusenko et al. 2013). The distribution of this trait among fungal taxa has not been extensively tested, although Shoun et al. (2012) screened 72 fungal genomes and found that 26% of them possessed homologues for at least one fungal denitrification gene.
Fungal genes for denitrification
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