Fig. 3.
Growth of S. aureus Kdp and Ktr mutants in low K+. Wildtype S. aureus (solid black circles) and mutant strains ΔkdpFABC (open purple diamonds) and ΔktrAΔkdpFABC (open green squares) were inoculated from overnight cultures to OD600=0.05 in K-CDM supplemented with KCl to the desired concentration.
A and B. Without supplemented KCl (A) and in 0.1 mM supplemented KCl (B), the ΔktrAΔkdpFABC double mutant was unable to grow, while the ΔkdpFABC single mutant had only a slight growth defect compared to wild-type. The ΔktrA (open red triangles) mutant is shown for reference.
C. In 0.5 mM added KCl, the ΔktrAΔkdpFABC strain had a slower rate of growth than the single ΔktrA mutant.
D. With KCl supplemented to 10 mM, all stains grew similarly.
A-D. Expression of ktrA (solid green squares) from plasmid pCM28 fully complemented the ΔktrAΔkdpFABC double mutant growth defects, and expression of kdpFABC (solid green diamonds) partially complemented growth of the ΔktrAΔkdpFABC strain in all conditions.
Data represents the mean of three independent experiments, with ± standard deviation.