FIG. 3.

B. anthracis and B. cereus PcrA helicases support in vitro replication of the heterologous pT181 plasmid. In vitro replication was performed using the RepC protein (+), and cell extracts (Ext) were made from either wild-type (Wt) or pcrA3 mutant S. aureus cells. PcrA helicases from S. aureus (Sa), B. cereus (Bc), and B. anthracis (Ba) were tested. The positions of replication intermediates (RI), open circular DNA (OC), supercoiled pT181cop608 DNA (SC), and single-stranded DNA (SS) are shown to the left of the gel.