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STRINGSTRING
STRING protein interaction network
Nodes:
Network nodes represent proteins
splice isoforms or post-translational modifications are collapsed, i.e. each node represents all the proteins produced by a single, protein-coding gene locus.
Node Color
colored nodes:
query proteins and first shell of interactors
white nodes:
second shell of interactors
Node Content
empty nodes:
proteins of unknown 3D structure
filled nodes:
some 3D structure is known or predicted
Edges:
Edges represent protein-protein associations
associations are meant to be specific and meaningful, i.e. proteins jointly contribute to a shared function; this does not necessarily mean they are physically binding to each other.
Known Interactions
from curated databases
experimentally determined
Predicted Interactions
gene neighborhood
gene fusions
gene co-occurrence
Others
textmining
co-expression
protein homology
Your Input:
Neighborhood
Gene Fusion
Cooccurence
Coexpression
Experiments
Databases
Textmining
[Homology]
Score
narXTwo-component system, narl family, nitrate/nitrite sensor histidine kinase narx; Acts as a sensor for nitrate/nitrite and transduces signal of nitrate availability to the NarL protein and of both nitrate/nitrite to the NarP protein. NarX probably activates NarL and NarP by phosphorylation in the presence of nitrate. NarX also plays a negative role in controlling NarL activity, probably through dephosphorylation in the absence of nitrate (598 aa)    
Predicted Functional Partners:
narL
Two-component system, narl family, nitrate/nitrite response regulator narl; This protein activates the expression of the nitrate reductase (narGHJI) and formate dehydrogenase-N (fdnGHI) operons and represses the transcription of the fumarate reductase (frdABCD) operon in response to a nitrate/nitrite induction signal transmitted by either the NarX or NarQ proteins
 0.999
narP
Two-component system, narl family, nitrate/nitrite response regulator narp; This protein activates the expression of the nitrate reductase (narGHJI) and formate dehydrogenase-N (fdnGHI) operons and represses the transcription of the fumarate reductase (frdABCD) operon in response to a nitrate/nitrite induction signal transmitted by either the NarX or NarQ proteins
  
 0.997
narK
Mfs transporter, nnp family, nitrate/nitrite transporter; Catalyzes nitrate uptake, nitrite uptake and nitrite export across the cytoplasmic membrane. Functions as a nitrate/nitrite exchanger, and protons are probably not co-transported with the substrate
 
  
 0.925
torS
Hybrid sensory histidine kinase in two-component regulatory system with torr; Member of the two-component regulatory system TorS/TorR involved in the anaerobic utilization of trimethylamine-N-oxide (TMAO). Detects the presence of TMAO in the medium and, in response, activates TorR via a four-step phosphorelay. When TMAO is removed, TorS can dephosphorylate TorR, probably by a reverse phosphorelay involving His- 860 and Asp-733
     
 0.862
citA
Two-component system, citb family, cit operon sensor histidine kinase cita; Member of the two-component regulatory system DpiA/DpiB, which is essential for expression of citrate-specific fermentation genes and genes involved in plasmid inheritance. Could be involved in response to both the presence of citrate and external redox conditions. Functions as a sensor kinase that phosphorylates DpiA in the presence of citrate
   
  
 0.826
dcuS
Two-component system, citb family, sensor histidine kinase dcus; Member of the two-component regulatory system DcuR/DcuS. Involved in the C4-dicarboxylate-stimulated regulation of the genes encoding the anaerobic fumarate respiratory system (frdABCD; nuoAN; dcuB; dcuC; sdhCDAB; etc.). Weakly regulates the aerobic C4- dicarboxylate transporter dctA. Activates DcuR by phosphorylation
   
  
 0.824
narG
Nitrate reductase / nitrite oxidoreductase, alpha subunit; The nitrate reductase enzyme complex allows E.coli to use nitrate as an electron acceptor during anaerobic growth. The alpha chain is the actual site of nitrate reduction
 
  
 0.795
phoQ
Sensory histidine kinase in two-component regulatory system with phop; Member of the two-component regulatory system PhoP/PhoQ involved in adaptation to low Mg(2+) environments and the control of acid resistance genes. In low periplasmic Mg(2+), PhoQ functions as a membrane-associated protein kinase that undergoes autophosphorylation and subsequently transfers the phosphate to PhoP, resulting in the expression of PhoP-activated genes (PAG) and repression of PhoP- repressed genes (PRG). In high periplasmic Mg(2+), acts as a protein phosphatase that dephosphorylates phospho-PhoP, resulti [...]
      
 0.752
glnL
Two-component system, ntrc family, nitrogen regulation sensor histidine kinase glnl; Member of the two-component regulatory system NtrB/NtrC, which controls expression of the nitrogen-regulated (ntr) genes in response to nitrogen limitation. Under conditions of nitrogen limitation, NtrB autophosphorylates and transfers the phosphoryl group to NtrC. In the presence of nitrogen, acts as a phosphatase that dephosphorylates and inactivates NtrC
      
 0.739
arcB
Two-component system, ompr family, aerobic respiration control sensor histidine kinase arcb; Member of the two-component regulatory system ArcB/ArcA. Sensor-regulator protein for anaerobic repression of the arc modulon. Activates ArcA via a four-step phosphorelay. ArcB can also dephosphorylate ArcA by a reverse phosphorelay involving His-717 and Asp-576
     
 0.703
Your Current Organism:
Escherichia coli K12 MG1655
NCBI taxonomy Id: 511145
Other names: E. coli str. K-12 substr. MG1655, Escherichia coli K12 substr. MG1655, Escherichia coli MG1655, Escherichia coli str. K-12 substr. MG1655, Escherichia coli str. K12 substr. MG1655, Escherichia coli str. MG1655, Escherichia coli strain MG1655
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