A Genetically Economical Family of Plasmid-Encoded Transcriptional Repressors Involved in Control of Plasmid Copy Number

During the last decade, the number of plasmids found to replicate by a rolling-circle mechanism has experienced an enormous increase. This group of plasmids now includes more than 200 replicons isolated from a variety of gram-positive and gram-negative bacteria as well as from archaea. All rolling