ATPase rates of the PcrA helicases from M. pneumoniae and M. genitalium.

aThe ATPase rates were determined either in the presence (+ ssDNA) or absence (- ssDNA) of φX174 virion DNA, as described in Materials and methods. The data represent averages (with standard deviation [SD]) from two independent measurements. Basal rates of ATP hydrolysis, which were determined in the absence of protein, were subtracted from the data.bThe average stimulation shows the average fold stimulation of the ATPase rate by ssDNA for each protein.cND, not determined.