Characterization of the orf1glnKamtB operon of Herbaspirillum seropedicae.
Herbaspirillum seropedicae is an endophytic nitrogen-fixing bacterium that colonizes economically important grasses. In this organism, the amtB gene is co-transcribed with two other genes: glnK that codes for a PII-like protein and orf1 that codes for a probable periplasmatic protein of unknown function. The expression of the orf1glnKamtB operon is increased under nitrogen-limiting conditions and is dependent on NtrC. An amtB mutant failed to transport methylammonium. Post-translational control of nitrogenase was also partially impaired in this mutant, since a complete switch-off of nitrogenase after ammonium addition was not observed. This result suggests that the AmtB protein is involved in the signaling pathway for the reversible inactivation of nitrogenase in H. seropedicae.
Noindorf
Lilian
L
Department of Biochemistry and Molecular Biology, Universidade Federal do Paraná, CP 19046, 81531-990, Curitiba, Brazil.
Rego
Fabiane G M
FG
Baura
Valter A
VA
Monteiro
Rose A
RA
Wassem
Roseli
R
Cruz
Leonardo M
LM
Rigo
Liu U
LU
Souza
Emanuel M
EM
Steffens
Maria B R
MB
Pedrosa
Fabio O
FO
Chubatsu
Leda S
LS
D001483:Base Sequence; D027682:Cation Transport Proteins / Q000235:genetics*; D005798:Genes, Bacterial; D042803:Herbaspirillum / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D016366:Open Reading Frames; D009876:Operon / Q000235:genetics*; D051922:PII Nitrogen Regulatory Proteins / Q000235:genetics*
D027682:Cation Transport Proteins; D051922:PII Nitrogen Regulatory Proteins