Fig. 3: AmbK is an epoxide hydrolase catalysing THP ring formation in ambruticin biosynthesis.

a Identification of ambK from the amb BGC. b HPLC traces of the So ce10 ΔambJ and ΔambK mutants. c Structural elucidation of ambruticin K (4). d Confirmation of AmbK as the epoxide hydrolase responsible for THP ring formation.