Figure 4

Chemical characterization of polycyclic tetramate macrolactams (PTMs) in the extract of S. xiamenensis 318 broth.
(A). UPLC-UV profiling at 254 nm. The HR-MS spectrum, the UV profile of one of the PTM peaks and the structure of ikarugamycin are shown. (B). The genes involved in PTM biosynthesis in S. xiamenensis 318 were aligned to the reported ikarugamycin biosynthesis gene cluster from Streptomyces sp. ZJ306 and its counterpart in S. griseus subsp. griseus NBRC 13350.