Deletion-insertion mapping of the region non-essential for functioning of the beta-subunit of Escherichia coli RNA polymerase

A plasmid has been constructed containing the gene of beta-subunit of RNA polymerase of Escherichia coli under control of the PR promoter of bacteriophage lambda. PR promoter may be induced by heating up to 42 degrees C. In frame insertions of different sequences between 989 and 990 or 1010 and 1011 codons of the rpoB gene do not inactivate the beta-subunit function. Deletions in the region of 1011-1027 codons result in inactivation of beta-subunit. We localized antigene determinant of monoclonal anti-beta-antibodies which do not inactivate RNA polymerase in vitro. The borders of non-essential region of beta-subunit were accurately determined.