Complex N acquisition by soil diazotrophs: how the ability to release exoenzymes affects N fixation by terrestrial free-living diazotrophs.

ABSTRACT: Terrestrial systems support a variety of free-living soil diazotrophs, which can fix nitrogen (N) outside of plant associations. However, owing to the metabolic costs associated with N fixation, free-living soil diazotrophs likely rely on soil N to satisfy the majority of cellular N demand and only fix atmospheric N under certain conditions. Culture-based studies and genomic data show that many free-living soil diazotrophs can access high-molecular weight organic soil N by releasing N-acquiring enzymes such as proteases and chitinases into the extracellular environment. Here, we formally propose a N acquisition strategy used by free-living diazotrophs that accounts for high-molecular weight N acquisition through exoenzyme release by these organisms. We call this the 'LAH N-acquisition stra

SUBMITTER: Norman JS 

PROVIDER: S-EPMC5270568 | biostudies-literature | 2017 Feb

REPOSITORIES: biostudies-literature