The Bacillus subtilis DnaD protein: a putative link between DNA remodeling and initiation of DNA replication

Abstract
The Bacillus subtilis DnaD protein is an essential protein and a component of the oriC and PriA primosomal cascades, which are responsible for loading the main replicative ring helicase DnaC onto DNA. We present evidence that DnaD also has a global DNA architectural activity, assembling into large nucleoprotein complexes on a plasmid and counteracting plasmid compaction in a manner analogous to that recently seen for the histone‐like Escherichia coli HU proteins. This DNA‐remodeling role may be an essential function for initiation of DNA replication in the Gram +ve B. subtilis, thus highlighting DnaD as the link between bacterial nucleoid reorganization and initiation of DNA replication.