FIGURE 4.

Select clinical isolates mediate contact-independent anti-S. aureus activity. (A) Strongly inhibitory clinical isolates (17/28) were defined as follows: visibly transparent ZOC of at least 2 mm with a defined edge. (B) A 0.2 μm filter was placed on top of BHIT agar plates seeded with S. aureus (S. epi-1 and S. sap were incubated with S. aureus LAC, C. amy-2 was incubated with S. aureus Mu50, and C. aur-1 was incubated with S. aureus 2014.N). A clinical isolate (as described above) was then spotted on top of the filter paper such that the clinical isolate and the S. aureus seeded agar plate were physically separated. Images of the ZOC were taken after 120 h of incubation at 28°C. Images are representative of three independent biological replicates. Scale bar = 10 mm.