Table 3

Comparison of helicase activity of E. coli PriA and N. gonorrhoeae PriA.

DNA Substrate

E. coli PriA1 % DNA Unwound

N. gonorrhoeae PriA2 % DNA Unwound


25 bp fork

83 ± 3

61 ± 6

40 bp fork

28 ± 8

37 ± 7

25 bp partial duplex

23 ± 2

17 ± 4


1Cadman et al. J Biol Chem 2005, 280(48):39693-39700.

2This study.

In this study, the 25 bp fork substrate is Fork 2, the 40 bp fork substrate is Fork 3, and the 25 bp partial duplex substrate is 3' Overhang. The helicase activity for each PriA homolog is the mean percent of DNA unwound by 5 nM PriA on 1 nM DNA substrate and in the absence of its cognate PriB. Mean values from Cadman et al. are derived from two independent experiments, and mean values from this study are derived from three independent experiments. Associated uncertainty values are one standard deviation of the mean.

Feng et al. BMC Microbiology 2011 11:189   doi:10.1186/1471-2180-11-189

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