Biosynthesis of a new skyllamycin in : a cytochrome P450 forms an epoxide in the cinnamoyl chain.

Activation of a silent gene cluster in leads to synthesis of a cinnamoyl-containing non-ribosomal peptide (CCNP) that is related to skyllamycins. This novel CCNP was isolated and its structure was interrogated using mass spectrometry and nuclear magnetic resonance spectroscopy. The isolated compound is an oxidised skyllamycin A in which an additional oxygen atom is incorporated in the cinnamoyl side-chain in the form of an epoxide.