Cloning and functional characterisation of a cis-muuroladiene synthase from black peppermint (Mentha × piperita) and direct evidence for a chemotype unable to synthesise farnesene

A novel sesquiterpene synthase has been cloned from Mentha x piperita, whose main products are cis-muurola-3,5-diene and cis-muurola-4(14)5-diene. An inactive E-β-farnesene synthase contributed to the lack of detectable farnesene in this ecotype.