The nucleotide sequence of the lac operator

Proc Natl Acad Sci U S A. 1973 Dec;70(12):3581-4. doi: 10.1073/pnas.70.12.3581.


The lac repressor protects the lac operator against digestion with deoxyribonuclease. The protected fragment is double-stranded and about 27 base-pairs long. We determined the sequence of RNA transcription copies of this fragment and present a sequence for 24 base pairs. It is: 5'--T G G A A T T G T G A G C G G A T A A C A A T T 3' 3'--A C C T T A A C A C T C G C C T A T T G T T A A 5' The sequence has 2-fold symmetry regions; the two longest are separated by one turn of the DNA double helix.

MeSH terms

  • Base Sequence
  • DNA, Bacterial / analysis*
  • Electrophoresis, Polyacrylamide Gel
  • Escherichia coli / analysis*
  • Escherichia coli / metabolism
  • Hydrolysis
  • Lactose / metabolism*
  • Nucleotides / analysis*
  • Operon*
  • Phosphorus Radioisotopes
  • Polynucleotides / analysis
  • Ribonucleases


  • DNA, Bacterial
  • Nucleotides
  • Phosphorus Radioisotopes
  • Polynucleotides
  • Ribonucleases
  • Lactose

Associated data

  • GENBANK/J01636
  • GENBANK/J01637
  • GENBANK/K01483
  • GENBANK/K01793