Kind Discrimination and Competitive Exclusion Mediated by Contact-Dependent Growth Inhibition Systems Shape Biofilm Community Structure
Figure 5
Dependence of bacterial numbers on CDI-mediated competition between opposing CDI+ bacteria.
A) The log competitive index (C.I. (Log)) is plotted for competitions between Bt-Bp1106a-1 and Bt-Bp1106a-2 bacteria at a 1∶1 starting ratio (with and without immunity as indicated) in the center (C) and edge (E) of colony biofilms. A positive C.I. (Log) indicates the inhibitor bacteria outcompeted the target bacteria, and a negative C.I. (Log) indicates the target bacteria outcompeted the inhibitor bacteria. B) The log competitive index (C.I. (Log)) is plotted for competitions between Bt-Bp1106a-1 and Bt-Bp1106a-2 bacteria at the indicated starting ratios. A positive C.I. (Log) indicates Bt-Bp1106a-1 bacteria outcompeted Bt-Bp1106a-2 bacteria. All samples were taken at 24 hours. Blue data points indicate the C.I. (Log). Red data points indicate only the “winning” (outcompeting) strain was recovered, the actual C.I. is therefore greater than or equal to the represented value.