TY - JOUR
T1 - Nitrogen and oxygen regulation of Bacillus subtilis nasDEF encoding NADH-dependent nitrite reductase by TnrA and ResDE
AU - Nakano, Michiko M.
AU - Hoffmann, Tamara
AU - Zhu, Yi
AU - Jahn, Dieter
PY - 1998/10
Y1 - 1998/10
N2 - The nitrate and nitrite reductases of Bacillus subtilis have two different physiological functions. Under conditions of nitrogen limitation, these enzymes catalyze the reduction of nitrate via nitrite to ammonia for the anabolic incorporation of nitrogen into biomolecules. They also function catabolically in anaerobic respiration, which involves the use of nitrate and nitrite as terminal electron acceptors. Two distinct nitrate reductases, encoded by narGHI and nusBC, function in anabolic and catabolic nitrogen metabolism, respectively. However, as reported herein, a single NADH- dependent, soluble nitrite reductase encoded by the nasDE genes is required for both catabolic and anabolic processes. The nasDE genes, together with nasBC (encoding assimilatory nitrate reductase) and nasF (required for nitrite reductase siroheme cofactor formation), constitute the has operon. Data presented show that transcription of nasDEF is driven not only by the previously characterized nus operon promoter but also from an internal promoter residing between the nasC and nasd genes. Transcription from both promoters is activated by nitrogen limitation during aerobic growth by the nitrogen regulator, TnrA. However, under conditions of oxygen limitation, nasDEF expression and nitrite reductase activity were significantly induced. Anaerobic induction of nasDEF required the ResDE two-component regulatory system and the presence of nitrite, indicating partial coregulation of NasDEF with the respiratory nitrate reductase NarGHI during nitrate respiration.
AB - The nitrate and nitrite reductases of Bacillus subtilis have two different physiological functions. Under conditions of nitrogen limitation, these enzymes catalyze the reduction of nitrate via nitrite to ammonia for the anabolic incorporation of nitrogen into biomolecules. They also function catabolically in anaerobic respiration, which involves the use of nitrate and nitrite as terminal electron acceptors. Two distinct nitrate reductases, encoded by narGHI and nusBC, function in anabolic and catabolic nitrogen metabolism, respectively. However, as reported herein, a single NADH- dependent, soluble nitrite reductase encoded by the nasDE genes is required for both catabolic and anabolic processes. The nasDE genes, together with nasBC (encoding assimilatory nitrate reductase) and nasF (required for nitrite reductase siroheme cofactor formation), constitute the has operon. Data presented show that transcription of nasDEF is driven not only by the previously characterized nus operon promoter but also from an internal promoter residing between the nasC and nasd genes. Transcription from both promoters is activated by nitrogen limitation during aerobic growth by the nitrogen regulator, TnrA. However, under conditions of oxygen limitation, nasDEF expression and nitrite reductase activity were significantly induced. Anaerobic induction of nasDEF required the ResDE two-component regulatory system and the presence of nitrite, indicating partial coregulation of NasDEF with the respiratory nitrate reductase NarGHI during nitrate respiration.
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U2 - 10.1128/jb.180.20.5344-5350.1998
DO - 10.1128/jb.180.20.5344-5350.1998
M3 - Article
C2 - 9765565
AN - SCOPUS:0031691173
SN - 0021-9193
VL - 180
SP - 5344
EP - 5350
JO - Journal of bacteriology
JF - Journal of bacteriology
IS - 20
ER -