Fig. 6: Heterogeneous growth kinetics and variable founder cell number determine competitive growth outcomes.
From: Fragmented micro-growth habitats present opportunities for alternative competitive outcomes
a Schematic of the observation chip used to track population growth within single droplets over time; figure panel redrawn after Fig. 1b from Ref. 52. b Time series examples of two droplets with the same number of founder cells for both P. putida and P. veronii, but with different outcomes. c Growth in individual droplets (each line a single droplet) of either strain in mono- or co-culture. Inferred maximum specific population growth rates (d) and lag times (e) in individual droplets of (c) (n = number of droplets with time-lapse observations). Averaged data is represented in box plots (median, upper and lower quartile, whiskers extending to the most extreme data points not considered outliers) with individual data points shown on top. P-values from two-sided t-testing. f Different growth trajectories of pairs with both a single founder cell, showing productivity of each member as its specific fluorescence (non-transformed AF-values). Black dots indicate final AF-productivities (t = 48 h). g Stationary phase per-strain productivity in mix droplets as a function of founder cell number (colours showing the difference in the number of starting cells, towards P. putida majority in green or P. veronii majority in magenta). h Effect of founder cell census on the ratio of stationary phase productivities (mean stationary AF-values) of P. putida (PPU) and P. veronii (PVE) in mix droplets. The initial number of both P. putida and P. veronii cells is indicated on the x-axis. Variation in the productivity ratio is best explained by variations in growth rates (µPVE) and lag times (lagPVE) of P. veronii (General linearized mixed effects model, r2 = 0.8236, see Supplementary Table 2). Effect of founder cell census on the variance in the measured maximum population growth rates (i) and lag times (j) of either strain in droplets (mono and mix combined). P-values from Brown-Forsythe test. Source data are provided as source data file.
