Part:BBa_K4115002

NifA(nif-specific transcriptional activator)

The coding sequence of the nifA protein in the nitrogen-fixing gene cluster.

The nifA protein encoded by the nifA sequence is a transcriptional activator that can activate the transcription of the downstream nifH promoter under the influence of cytosolic nitrogen sources or oxygen, and is a key activator of nitrogen-fixing gene clusters. The nitrogen fixation gene can be regulated by knocking out the native nifA sequence and replacing it with the nifA sequence added with regulatory elements.
Sequence and Features

Assembly Compatibility:

• 10
  INCOMPATIBLE WITH RFC[10]

  Illegal PstI site found at 136
  Illegal PstI site found at 1000
  
• 12
  INCOMPATIBLE WITH RFC[12]

  Illegal PstI site found at 136
  Illegal PstI site found at 1000
  
• 21
  INCOMPATIBLE WITH RFC[21]

  Illegal BamHI site found at 637
  
• 23
  INCOMPATIBLE WITH RFC[23]

  Illegal PstI site found at 136
  Illegal PstI site found at 1000
  
• 25
  INCOMPATIBLE WITH RFC[25]

  Illegal PstI site found at 136
  Illegal PstI site found at 1000
  Illegal NgoMIV site found at 1257
  Illegal NgoMIV site found at 1452
  Illegal NgoMIV site found at 1527
  Illegal AgeI site found at 886
  
• 1000
  INCOMPATIBLE WITH RFC[1000]

  Illegal BsaI site found at 1095
  Illegal SapI site found at 318
  Illegal SapI site found at 939
  

Usage and Biology

The A. caulinodans nif cluster is difficult to engineer because it is large (64 kb total, 76 genes), distributed across multiple loci and has a complex regulatory network. Fortunately, studies have shown that the expression level of nitrogen fixation genes can be efficiently regulated by regulating the expression of a single gene corresponding to nifA. [1]
Therefore, we followed the regulatory scheme pointed out in the literature, knocked out the original nifA gene of nitrogen-fixing bacteria regulated by ammonium root and replaced it with the nifA coding sequence regulated by other artificially designed parts. The expressed protein then activates the downstream receiving part PnifHBBa_K4115014, which in turn regulates the nif gene cluster (nitrogen-fixing gene cluster).

Figure 1: aaa