The sigma-70 subunit from Escherichia coli C differs from that of E. coli K-12.

The nucleotide sequence of the rpoD gene (encoding the primary sigma-70 (sigma 70) subunit of RNA polymerase) from Escherichia coli C was determined. This gene differs from that of E. coli K-12 by a 30-bp deletion and five single-bp substitutions, resulting in a sigma 70 subunit with three amino acid (aa) changes and a deletion of ten acidic aa.