Part:BBa_K4345007

NarX

NarX is a part of NarX-NarL two component nitrate sensing system in Escherichia coli. They are responsible for the expression of anaerobic respiratory genes. NarX is a histidine kinases that independently detect the presence of nitrate an transmit the signal to NarL. After autophosphorylation and thus dimerization of NarX or NarQ, NarL is phosphorylated. This enables the activated NarL to bind DNA and induce expression of specific genes. Both NarX and narQ contain two conserved histidine residues that correspond to the autophosphorylation sites of other, homologous, sensor-transmitter proteins (Cavicchioli et al., 1995). Cheung & Hendrickson (2009) elucidated the structure of the histidine kinase in the apo- and holo-state to be a four-helix bundle.

Sequence and Features

Assembly Compatibility:

• 10
  INCOMPATIBLE WITH RFC[10]

  Illegal PstI site found at 659
  
• 12
  INCOMPATIBLE WITH RFC[12]

  Illegal PstI site found at 659
  
• 21
  INCOMPATIBLE WITH RFC[21]

  Illegal XhoI site found at 260
  
• 23
  INCOMPATIBLE WITH RFC[23]

  Illegal PstI site found at 659
  
• 25
  INCOMPATIBLE WITH RFC[25]

  Illegal PstI site found at 659
  
• 1000
  COMPATIBLE WITH RFC[1000]

Usage and Biology

This particular narX protein was derived from E. coli.

Image obtained from Cheung & Hendrickson, 2009