Transcription-induced cytosine-to-thymine mutations are not dependent on sequence context of the target cytosine.

We showed previously that transcription of a plasmid-borne kan allele increases C-to-T mutations in the nontranscribed strand. Using two new plasmid-borne kan alleles, one cmp allele, and a chromosomal kan allele, we found in this study that transcription-induced mutations are not limited to specific genes, alleles, or locations and are likely to be a general property of transcript elongation in Escherichia coli.