Which Nucleotides in the "-10" Region Are Crucial to Obtain a Fully Active MalT-dependent Promoter?

J Mol Biol. 1994 May 20;238(5):643-8. doi: 10.1006/jmbi.1994.1324.

Abstract

We have replaced the hexanucleotide corresponding to the "-10" region of malPp, a positively regulated promoter from Escherichia coli, by random nucleotide sequences and isolated 48 different variants that were as active as the wild-type promoter. Analysis of the nucleotide sequence of their "-10" region strongly suggests that the nature of the nucleotide present at three positions plays a crucial role: 46 of the 48 malPp variants contained C or T at position -12, A at position -11 and T at position -7. The nucleotide composition at the three other positions seems to be much more flexible. The features of these "-10" regions are similar to those of the constitutive promoters, but some significant differences are noticeable and will be discussed. In contrast to other positively regulated promoters, none of the various "-10" regions, including the consensus sequence TATAAT, led to a constitutive promoter.

MeSH terms

  • Bacterial Proteins / genetics*
  • Bacterial Proteins / metabolism
  • Base Sequence
  • DNA, Bacterial / analysis
  • DNA-Binding Proteins*
  • Escherichia coli / genetics*
  • Escherichia coli Proteins*
  • Gene Expression Regulation, Bacterial / genetics*
  • Molecular Sequence Data
  • Mutagenesis, Site-Directed
  • Oligodeoxyribonucleotides
  • Operon
  • Promoter Regions, Genetic / genetics*
  • Sequence Analysis, DNA
  • Transcription Factors / genetics*
  • Transcription Factors / metabolism

Substances

  • Bacterial Proteins
  • DNA, Bacterial
  • DNA-Binding Proteins
  • Escherichia coli Proteins
  • MalT protein, E coli
  • Oligodeoxyribonucleotides
  • Transcription Factors