Fig. 1: Klebsiella and Pseudomonas exhibited collective range expansion under CTX treatment at the cost of Klebsiella’s growth.
From: Spatial proximity dictates bacterial competition and expansion in microbial communities
Kp: Klebsiella, Pa: Pseudomonas, CTX: Cefotaxime. Source data are provided as a Source Data file. a Pseudomonas tolerated CTX treatment better than Klebsiella. Liquid media were inoculated with Klebsiella (dark red) or Pseudomonas (cyan) at OD600 = ~2.1×10−5 (from dilutions of a cell suspension with OD600 > 0.05), without (top) or with CTX (2.5 μg ml−1, bottom). Curves and shades show average and standard deviation, respectively, from n = 2 biological replicates, each with three technical replicates. b Pseudomonas dominated Klebsiella under the CTX treatment in well-mixed co-cultures. Liquid media were inoculated with a 1:1 mixture of the two species at OD600 = ~2.1×10−5, incubated for 27 h, and then plated to determine relative abundances (Supplementary Fig. 4b). Symbols denote n = 3 independent replicates (solid/open markers show technical replicates); diamond indicates data from fluorescently labeled strains. Bars and error bars represent mean and standard deviation from independent experiments after averaging technical replicates. c Pseudomonas range expansion was suppressed by CTX and rescued by Klebsiella. 20 ml of swarming agar (0.55%) media were center inoculated with 1 μl of Klebsiella or Pseudomonas (OD600 = ~0.43). Colony images were captured at 24 h, processed, and analyzed for colony areas using a custom Python script (Methods; Supplementary Fig. 3). Images shown were equally adjusted for brightness/contrast. Dish diameter: 100 mm. See Supplementary Fig. 7 for raw images from n = 3 biological replicates. d The rescue of the coculture range expansion occurred at the expense of Klebsiella’s growth. In the same experiments as in (c), agar media were center inoculated with 1 μl of 1:1 mixture of the two species (OD600 = ~0.43) and imaged after 24 h. Then, whole colonies were harvested with 5 ml of saline, and relative abundances were estimated by plating (Supplementary Fig. 4b). Symbols indicate n = 3 independent experiments, with solid/open markers showing technical replicates. Bars and error bars show mean and standard deviation of independent experiments after averaging technical replicates. Images shown were equally adjusted for brightness/contrast.
