Escherichia coli tryptophan operon leader mutations, which relieve transcription termination, are cis-dominant to trp leader mutations, which increase transcription termination
Zurawski, G.; Yanofsky, C.
Journal of Molecular Biology 142(1): 123-129
Strains with increased expression of the Escherichia coli trp operon were selected from trp leader mutants, which have decreased trp operon expression. The trp leader nucleotide sequences of 22 mutant strains with trp operon-linked mutations were determined. The strains were shown to be either true revertants or to have secondary site mutations in the trp leader region. All the secondary site mutations were located immediately proximal to the transcription termination site and overlapped with previously identified single base-pair mutations, which relieve transcription termination.