Part:BBa_K4392005

exaA alcohol dehydrogenase promoter

This promoter is present upstream of the quinoprotein alcohol dehydrogenase gene in A. brasilense sp7.

In the study by Singh et. al[1], using an exaA:lacZ fusion, the activity of this promoter is found to be induced significantly in the presence of glycerol, fructose, and primary and secondary long-chain alcohols(C4-C6). Short-chain alcohols caused the least induction while glycerol caused the maximum induction. It has also been found that this is a σ54-dependent promoter.

It was found that in the exaA promoter region, there is an inverted repeat sequence whose mutation leads to a drastic effect on the exaA promoter activity. It was assumed that this region might be the binding site for a positive regulator of exaA transcription. EMSA was used to examine the binding ability of the recombinant EraR protein to an inverted repeat sequence. It was seen that the EraR protein retarded the mobility of the W.T. probe at all concentrations but failed to retard the mobility of the disrupted sequence[1]. This proved that the inverted repeat sequence is a binding site for the EraR response regulator.

Using a bacterial two-hybrid system, it was found that the sigma54 transcriptional factor physically interaceted with the EraR protein to enhance the promoter activity[1]

Reference [1] Singh VS, Dubey AP, Gupta A, Singh S, Singh BN, Tripathi AK. Regulation of a Glycerol-Induced Quinoprotein Alcohol Dehydrogenase by σ54 and a LuxR-Type Regulator in Azospirillum brasilense Sp7. J Bacteriol. 2017 Jun 13;199(13):e00035-17. doi: 10.1128/JB.00035-17.

Sequence and Features

Assembly Compatibility:

• 10
  COMPATIBLE WITH RFC[10]
• 12
  COMPATIBLE WITH RFC[12]
• 21
  COMPATIBLE WITH RFC[21]
• 23
  COMPATIBLE WITH RFC[23]
• 25
  INCOMPATIBLE WITH RFC[25]

  Illegal AgeI site found at 68
  
• 1000
  INCOMPATIBLE WITH RFC[1000]

  Illegal BsaI site found at 71