Fig. 5
From: Biosynthesis of C-nucleoside antibiotics in actinobacteria: recent advances and future developments
The gene clusters and corresponding pathways for FOR-A and PRF-A biosynthesis. a Genetic organization of the PRF-A and FOR-A gene clusters. The PRF-A gene cluster (prf) was from S. candidus NRRL 3601, and the FOR-A and COF gene cluster was from Nocardia interforma ATCC 21072 and from S. kaniharaensis ATCC 21070, respectively. b Proposed pathways to FOR-A and PRF-A. They share identical steps at the early stage prior to the construction of C-nucleoside scaffolds. HDCP, 4-hydroxy-3,5-dicarboxypyrazole; DCOP, 3,5-dicarboxy-4-oxo-4,5-dihydropyrazole; ADCP, 4-amino-3,5-dicarboxypyrazole