Mechanism of regulation of the bifunctional histidine kinase NtrB in Escherichia coli.
NtrB is the bifunctional histidine kinase for nitrogen regulation. Dependent on the availability of nitrogen, it either autophosphorylates and serves as the phosphodonor for its cognate response regulator, NtrC, or, it promotes the rapid dephosphorylation of NtrC-P. The activity of NtrB depends on the interaction of two subdomains within its transmitter domain, the H-domain and the kinase domain. Both phosphotransfer activity and phosphatase activity reside in the H-domain. When separately expressed, this domain acts as a phosphatase. Interaction with the kinase domain results in the inhibition of the phosphatase activity and the phosphorylation of the conserved histidine of the H-domain.
Weiss
Verena
V
Department of Biology, University of Konstanz, Germany. weiss@chclu.chemie.uni-konstanz.de
Kramer
Günter
G
Dünnebier
Thomas
T
Flotho
Annette
A
D004926:Escherichia coli / Q000201:enzymology* / Q000235:genetics; D029968:Escherichia coli Proteins / Q000235:genetics / Q000378:metabolism; D015964:Gene Expression Regulation, Bacterial; D009584:Nitrogen / Q000378:metabolism; D010749:Phosphoprotein Phosphatases / Q000235:genetics / Q000378:metabolism*; D011494:Protein Kinases / Q000235:genetics / Q000378:metabolism*
D029968:Escherichia coli Proteins; D011494:Protein Kinases; C055699:protein kinase-phosphatase NTRB; D010749:Phosphoprotein Phosphatases; D009584:Nitrogen