Fig. 1: Transcriptome analysis of S. coelicolor and M. xanthus under pure-culture and coculture conditions.

a Coculture of S. coelicolor and M. xanthus. Solid CTT agar plates were inoculated with a lawn of M. xanthus and S. coelicolor. For pure-culture samples, S. coelicolor and M. xanthus were spread the same way but with identical species. b RNA-Seq sampling was performed after 3 (T1), 5 (T2), 7 (T3), and 9 days (T4) after inoculation. T1 was immediately after M. xanthus contacted S. coelicolor. c Actinorhodin measurement for pure-cultured and cocultured S. coelicolor. Error bars indicate standard deviation (s.d.) of three biological replicates. d Morphology of S. coelicolor and M. xanthus during coculture. Cell morphology was determined at the last time point (T4) using scanning electron microscopy (SEM). The yellow arrow indicates M. xanthus cells, and the red arrow indicates abnormal hyphae of S. coelicolor. Bar: 2 μm. Mx M. xanthus, Sc S. coelicolor. e Upregulated genes involved in the actinorhodin biosynthesis pathway. The four boxes next to the gene name denote T1–4. The orange boxes indicate that genes showing statistically significant upregulation (p < 0.05) at the corresponding time point. f Upregulated genes involved in the myxochelin biosynthesis pathway and iron acquisition system. Gray and red cylinders represent outer membrane receptors associated with heme and siderophore, respectively. Gray- and red-colored circles indicate periplasmic iron complex binding protein. Gray and red rounded rectangles indicate associations of the iron ferric compound ABC transporter with heme and siderophore, respectively. Yellow–green circles represent myxochelin. DHBA dihydroxybenzoic acid, OM outer membrane, IM inner membrane. g Myxochelin A production of pure-cultured and cocultured M. xanthus. Error bars indicate standard deviation (s.d.) of three biological replicates.