Interactions between the RepB initiator protein of plasmid pMV158 and two distant DNA regions within the origin of replication.

ABSTRACT: Plasmids replicating by the rolling circle mode usually possess a single site for binding of the initiator protein at the origin of replication. The origin of pMV158 is different in that it possesses two distant binding regions for the initiator RepB. One region was located close to the site where RepB introduces the replication-initiating nick, within the nic locus; the other, the bind locus, is 84 bp downstream from the nick site. Binding of RepB to the bind locus was of higher affinity and stability than to the nic locus. Contacts of RepB with the bind and nic loci were determined through high-resolution footprinting. Upon binding of RepB, the DNA of the bind locus follows a winding path in its contact with the protein, resulting in local distortion and bending of the double-helix. On s

SUBMITTER: Ruiz-Maso JA 

PROVIDER: S-EPMC1851628 | biostudies-literature | 2007

REPOSITORIES: biostudies-literature