Structures and Biosynthetic Pathway of Coprisamides C and D, 2-Alkenylcinnamic Acid-Containing Peptides from the Gut Bacterium of the Carrion Beetle <i>Silpha perforata</i>.
Shin YH, Ban YH, Kim TH, Bae ES, Shin J, Lee SK, Jang J, Yoon YJ, Oh DC.
Coprisamides C and D (<b>1</b> and <b>2</b>) were isolated from a gut bacterium, <i>Micromonospora</i> sp. UTJ3, of the carrion beetle <i>Silpha perforata</i>. Based on the combined analysis of UV, MS, and NMR spectral data, the planar structures of <b>1</b> and <b>2</b> were elucidated to be unreported derivatives of coprisamides A and B, cyclic depsipeptides bearing a 2-alkenylcinnamic acid unit and the unusual amino acids β-methylaspartic acid and 2,3-diaminopropanoic acid. The absolute configuration of <b>1</b> was determined using the advanced Marfey's method, phenylglycine methyl ester derivatization, and <i>J</i>-based configuration analysis. The biosynthetic gene clusters for the coprisamides were investigated based on genomic data from coprisamide-producing strains <i>Micromonospora</i> sp. UTJ3 and <i>Streptomyces</i> sp. SNU533. Coprisamide C (<b>1</b>) was active against the <i>Mycobacterium tuberculosis</i> mc<sup>2</sup> 6230 strain.