Supporting Information: contains supplementary or supporting methods and figures from Deciphering a survival strategy during the interspecific competition between <i>Bacillus cereus</i> MSM-S1 and <i>Pseudomonas</i> sp. MSM-M1

Interspecific competition in bacteria governs colony growth dynamics and pattern formation. Here, we demonstrate an interesting phenomenon of interspecific competition between <i>Bacillus cereus</i> MSM-S1 and <i>Pseudomonas</i> sp<i>.</i> MSM-M1, where secretion of an inhibitor by <i>Pseudomonas</i> sp<i>.</i> is used as a strategy for the survival. Although <i>B. cereus</i> grows faster than <i>Pseudomonas</i> sp.; in the presence of <i>Pseudomonas</i> sp., the population of <i>B. cereus</i> reduces significantly, whereas <i>Pseudomonas</i> sp. do not show any marked alteration in their population growth. Appearance of a zone of inhibition between growing colonies of two species on nutrient agar prevents the expanding front of the MSM-S1 colony from accessing and depleting nutrients in the region occupied by MSM-M1, thereby aiding the survival of the slower growing MSM-M1 colonies. To support our experimental results, we present simulations, based on a chemotactic model of colony growth dynamics. We demonstrate that the chemical(s) secreted by <i>Pseudomonas</i> sp. is responsible for the observed inhibition of growth and spatial pattern of the <i>B. cereus</i> MSM-S1 colony. Our experimental results are in excellent agreement with the numerical results and confirm that secreted inhibitors enable <i>Pseudomonas</i> sp. to survive and coexist in the presence of faster growing <i>B. cereus</i>, in a common niche.