D. discoideum axenic strains used in the study were AX3 (Dictybase ID: DBS0235545), DH1 (Dictybase ID: DBS0302388),
phg2 (Dictybase ID: DBS0302388),
pdsA (Dictybase ID: DBS0237030), and
carA (Dictybase ID: DBS0236438). All the strains were cultured in autoclaved HL5 medium (per L, 5 g proteose peptone, 5 g thiotone E peptone, 5 g yeast extract, from USBIO, 10 g glucose, 0.35 g Na
2HPO
4*7H
2O, 0.35 g KH
2PO
4 from Sigma-Aldrich, pH=6.7) at 22°C if not mentioned otherwise. In experiments on nutritional effect we used: FM minimal medium (Formedium), NS (per L, 15.2 g peptone, 7.6 g yeast extract, from USBIO, 5mg Na
2HPO
4, 5mg KH
2PO
4, from Sigma-Aldrich, pH=6.7) and NS with 85mM glucose (Sigma-Aldrich) added after autoclaving
15 (link). The bacterial species used as the nutritional source in our study was
Klebsiella aerogenes. Heat killed bacterial cultures were prepared by centrifuging 50mL of overnight LB cultures at 4°C, 5000 g for 10min and diluting the pellet in 1mL KK2 buffer (per L, 22 g KH
2PO
4, 7.0 g K
2HPO
4, Sigma-Aldrich). The suspension was incubated for 20min at 80°C and stored at -20°C.