Control of Azospirillum brasilense NifA activity by P II : effect of replacing Tyr residues of the NifA N-terminal domain on NifA activity

Florence Arsène (1) , Pierre-Alexandre Kaminski (1) , Claudine Elmerich (1)

1 Physiologie Cellulaire

It was previously reported that the N-terminal domain of Azospirillum brasilense NifA was a negative regulator of the NifA activity and that the PII protein prevented this inhibition under nitrogen fixing conditions. Here, we show that a mutation of a single Tyr residue at position 18 of the N-terminal domain of NifA led to an active NifA protein that did not require PII for activation under nitrogen fixation conditions.

Keywords: Nitrogen fixation; NifA activity; glnB; Azospirillum brasilense

Domains: Microbiology and Parasitology

Florence Arsène, Pierre-Alexandre Kaminski, Claudine Elmerich. Control of Azospirillum brasilense NifA activity by P II : effect of replacing Tyr residues of the NifA N-terminal domain on NifA activity. FEMS Microbiology Letters, 1999, 179 (2), pp.339-343. ⟨10.1111/j.1574-6968.1999.tb08747.x⟩. ⟨pasteur-03659718⟩