Genetic Determinants of Ammonium Excretion in nifL Mutants of Azotobacter vinelandii.

ABSTRACT: The ubiquitous diazotrophic soil bacterium Azotobacter vinelandii has been extensively studied as a model organism for biological nitrogen fixation (BNF). In A. vinelandii, BNF is regulated by the NifL-NifA two-component system, where NifL acts as an antiactivator that tightly controls the activity of the nitrogen fixation-specific transcriptional activator NifA in response to redox, nitrogen, and carbon status. While several studies reported that mutations in A. vinelandii nifL resulted in the deregulation of nitrogenase expression and the release of large quantities of ammonium, knowledge about the specific determinants for this ammonium-excreting phenotype is lacking. In this work, we report that only specific disruptions of nifL lead to large quantities of ammonium accumu

SUBMITTER: Mus F 

PROVIDER: S-EPMC8939361 | biostudies-literature | 2022 Mar

REPOSITORIES: biostudies-literature