Genome-Based Mining of Carpatamides I-M and Their Candidate Biosynthetic Gene Cluster

Chemically investigating the marine-derived Streptomyces parvus 1268 led to the isolation of a new compound of carpatamide I (1). Subsequent genomic analysis identified its candidate biosynthetic gene cluster ctd of approximately 44 kb. In order to obtain more carpatamide derivatives, we conducted the upregulation of Ctd14, which is a positive regulator, and obtained improvement of carpatamide I and four new compounds of carpatamides J-M (2-5). The structures of the aforementioned five new isolates were identified by a combination of ESI-HRMS as well as one-dimensional (1D) and two-dimensional (2D) spectral NMR datasets. Bioassay results showed that compounds 1-5 displayed anti-inflammatory activity and weak cytotoxicity against cell lines of A549, HT-29, and HepG2.