The Dynamic Structure of Jadomycin B and the Amino Acid Incorporation Step of Its Biosynthesis

摘要

The jadomycins are a unique family of angucycline derived antibiotics because of their pentacyclic 8H-benz[b]oxazolo[3,2-f]-phenanthridine backbone, which includes a dihydropyridine and an oxazolone ring. This unusual ring assembly is distinctive for the jadomycins, but its biosynthetic formation is unclear. However, it is obvious that the nitrogen heteroatom is derived from the amino acid isoleucine, a major constituent of the jadomycin production medium. Jadomycin B (5) is the principal product of Streptomyces Venezuelae ISP5230 when this strain is fermented under stress conditions, such as heat shock, ethanol treatment, or phage infection, while chloramphenicol is the only antibiotic produced under normal growth conditions.