Structure and interactions of the Bacillus subtilis sporulation inhibitor of DNA replication, SirA, with domain I of DnaA.

ABSTRACT: Chromosome copy number in cells is controlled so that the frequency of initiation of DNA replication matches that of cell division. In bacteria, this is achieved through regulation of the interaction between the initiator protein DnaA and specific DNA elements arrayed at the origin of replication. DnaA assembles at the origin and promotes DNA unwinding and the assembly of a replication initiation complex. SirA is a DnaA-interacting protein that inhibits initiation of replication in diploid Bacillus subtilis cells committed to the developmental pathway leading to formation of a dormant spore. Here we present the crystal structure of SirA in complex with the N-terminal domain of DnaA revealing a heterodimeric complex. The interacting surfaces of both proteins are α-helical with predominantly

SUBMITTER: Jameson KH 

PROVIDER: S-EPMC4285326 | biostudies-literature | 2014 Sep

REPOSITORIES: biostudies-literature