Fig. 3: Lactate stress-induced community succession and interaction dynamics of pluralistic microbial consortia.

A Schematic of the biomass in the microbial consortia calculated by fluorescence intensity. The cartoon diagram on the left shows an inoculated culture of the ternary microbial consortia. The colonies at different distances were placed on separate agar plates. Specific steps for calculating biomass based on fluorescence intensity are described in the method section. Biomass comparison of A01 (B) and B01 (C) in monoculture and co-culture at different distances. Mono- represents monoculture. Co- represents co-culture. Schematic of monoculture is shown in Fig. 2B. The red dashed box indicates the distance at the spatial inflection point λx, where the fitness of A01 and B01 was similar. D Biomass ratios (fold change R = B01/A01) at different distances when A01 and B01 were inoculated with different initial inoculation ratios and incubated for 33 h. The red frame indicated the spatial distance at which the fold change R was maintained between 0.5 and 1.5 for different initial inoculation ratios. The data represent the values of three biological replicates. E The curve of biomass ratios (fold change R = B01/A01) at different distances when A01, B01, and EH1 were inoculated with different initial inoculation ratios and incubated for 33 h. The meaning of the red frame is the same as in D. The ratio at the top indicates the initial inoculation ratio, and the color of the circle in front of the ratio corresponds to the color of the curve in the figure. F Lactate stress-induced colonization ecology of quaternary microbial communities based on biomass ratios (fold change \(\bar{{{{\rm{R}}}}}\)), revealing niche occupancy (left), coexistence (middle), and invasion (right). Invaders were considered invasive when their biomass ratio (fold change \(\bar{{{{\rm{R}}}}}\) = A_i/N) was greater than 50%. The initial inoculation ratio was 1:1:1. N represents the maximum biomass, which is the sum of the biomass of A01, B01, and EH1 at 4.5 cm. A_i represents the biomass of individual strains in quaternary co-culture. The data in (B), (C), (E), and (F) represent the average of three biological replicates; see source data for SD.