A hybrid bacterial replication origin.

Max-Planck-Institut für molekulare Genetik, Ihnestrasse 73, D-14195 Berlin, Germany.
EMBO Reports (Impact Factor: 7.19). 12/2001; 2(11):1003-6. DOI: 10.1093/embo-reports/kve225
Source: PubMed

ABSTRACT We constructed a hybrid replication origin that consists of the main part of oriC from Escherichia coli, the DnaA box region and the AT-rich region from Bacillus subtilis oriC. The AT-rich region could be unwound by E. coli DnaA protein, and the DnaB helicase was loaded into the single-stranded bubble. The results show that species specificity, i.e. which DnaA protein can do the unwinding, resides within the DnaA box region of oriC.

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