Table 1.

Mutational analysis of RadA motifs

	% Survival (8 ng/ml CFX)
Plasmid	rad+	radAΔ
Vector	14 (± 5.6)	0.70 (± 0.36)
RadA wt	13 (± 1.9)	47 (± 8.9)
RadA C28Y	4.3 (± 1.6)	0.69 (± 0.27)
RadA K108R	1.5 (± 0.27)	0.25 (± 0.099)
RadA K258R	5.3 (± 1.1)	0.32 (± 0.094)
RadA S372A	11 (± 2.1)	26 (± 4.5)
RadA Δ(228–460)	6.6 (± 1.1)	0.91 (± 0.35)
RadA Δ(275–460)	9.9 (± 2.1)	0.69 (± 0.27)

Cultures of AB1157 or the isogenic radA deletion strain carrying the pWSK29 vector or plasmids containing the indicated RadA alleles were grown, diluted and plated on LB ampicillin plates with 8 ng/ml ciprofloxacin. Survival was determined after incubation at 37^° overnight. At least eight isolates of each strain were tested over 2 or more days. Standard errors of the mean are shown in parentheses. Survival of strains lacking plasmids was 49% for wild-type and 1.5% for the radAΔ strain.