A new nitrifying bacteria was isolated from the soil in a tea plantation. This ammonia oxidizing bacteria (AOB) was presumed to contribute to nitrification in strongly acidic agricultural soil. Although the process of nitrification, the microbial oxidation of ammonia to nitrate via nitrite, occurs in a wide range of acidic soils, the AOB that have been isolated from soil so far are acid-sensitive. The research of Hayatsu et al. from the Institute for Agro-Environmental Sciences, NARO reported that the isolated AOB can grow in the pH range of 5-7.5 and survive in highly acidic conditions until pH 2 by forming cell aggregates. By clarifying the genetic and physiological properties of the AOB, it is expected that nitrification in acidic soil will be suppressed that will lead to the development of an efficient technology to reduce nitrogen fertilizer runoff caused by nitrification and reduce adverse effects on the environment.
Masahito Hayatsu et al., An acid-tolerant ammonia-oxidizing γ-proteobacterium from soil. ISME Journal. 2017, http://doi.org/10.1038/ismej.2016.191