Morphology, taxonomy, and geographic distribution of the five C-1027 producers (color-coded). (A) Morphology of the four C-1027 alternative producers S. sp. CB00657, CB02329, CB02366, and CB03608 in comparison with the S. globisporus wild-type and AF40 mutant strains.(B) Taxonomic analysis of the four C-1027 alternative producers supporting their classification as Streptomyces species. The phylogenetic tree was constructed using the concatenated sequences of 16S rRNA, rpoB, and trpB of each strain, with representative Streptomyces species as controls and Micromonospora rifamycinica as an outgroup. (C) Geographic locations where the five C-1027 producers were isolated.