Urea-based mutualistic transfer of nitrogen in biological soil crusts.

ABSTRACT: Foundational to the establishment and recovery of biocrusts is a mutualistic exchange of carbon for nitrogen between pioneer cyanobacteria, including the widespread Microcoleus vaginatus, and heterotrophic diazotrophs in its "cyanosphere". In other such mutualisms, nitrogen is transferred as amino acids or ammonium, preventing losses through specialized structures, cell apposition or intracellularity. Yet, in the biocrust symbiosis relative proximity achieved through chemotaxis optimizes the exchange. We posited that further partner specificity may stem from using an unusual nitrogen vehicle, urea. We show that representative mutualist M. vaginatus PCC 9802 possesses genes for urea uptake, two ureolytic systems, and the urea cycle, overexpressing only uptake and the rare urea carboxylase/a

SUBMITTER: Heredia-Velasquez AM 

PROVIDER: S-EPMC11844795 | biostudies-literature | 2025 Jan

REPOSITORIES: biostudies-literature