Identification of the chromosomal replication origin from Thermus thermophilus and its interaction with the replication initiator DnaA

摘要: The chromosomal replication origin oriC and the gene encoding initiator protein DnaA from Thermus thermophilus have been identified cloned into an Escherichia coli vector system. is composed of 13 characteristically arranged boxes, binding sites for protein, AT-rich stretch, followed by dnaN gene. dnaA located upstream expresses a typical that follows division four domains, as with other members family. Here, we report purification Thermus-DnaA (Tth-DnaA) characterize interaction purified origin, regard to kinetics stoichiometry this interaction. Using gel retardation assays, surface plasmon resonance (SPR) electron microscopy, show that, unlike E. DnaA, Tth-DnaA does not recognize single box, instead cluster three tandemly repeated boxes minimal requirement specific binding. highest affinities are observed full-length or six clustered, boxes. Furthermore, high-affinity DNA-binding dependent on presence ATP. DnaA/oriC will be compared complex formation generated proteins.