title: DNA sequence of the gene for the outer membrane lipoprotein of E. coli: an extremely AT-rich promoter.
abstract: The outer membrane lipoprotein is the most abundant protein in an E. coli cell. Its structural gene (Ipp) was cloned into a lambda phage vector and the nucleotide sequence of a DNA fragment of 814 bp encompassing the Ipp gene was determined. The promoter region of the gene was found to have the following features. First, a segment of 261 bp preceding the transcription initiation site (-1 to -261) has a very high AT content of 70%, in contrast to 53% for the mRNA region of 322 bp, 44% for a segment of 127 bp after the transcription termination site and 49% for the average AT content of the E. coli chromosome. Second, in particular, of the first 45 bp upstream from the transcription initiation site (-1 to -45), 36 bases (80%) are A or T. Third, there is a heptanucleotide sequence homologous to the "Pribnow box," eight bases apart from the transcription initiation site. Fourth, a sequence homologous to the "RNA polymerase recognition site" exists on both strands between positions -27 and -39. Finally, there is a long dyad symmetry centered at the transcription initiation site.
mesh_terms: D000225:Adenine / Q000032:analysis; D001426:Bacterial Proteins / Q000235:genetics*; D001483:Base Sequence; D003001:Cloning, Molecular; D004269:DNA, Bacterial / Q000032:analysis / Q000235:genetics*; D004926:Escherichia coli / Q000235:genetics*; D008074:Lipoproteins / Q000235:genetics*; D008565:Membrane Proteins / Q000235:genetics*; D009876:Operon; D013941:Thymine / Q000032:analysis; D014158:Transcription, Genetic
chemical_list: D001426:Bacterial Proteins; D004269:DNA, Bacterial; D008074:Lipoproteins; D008565:Membrane Proteins; D000225:Adenine; D013941:Thymine