Description:
<jats:p>Oroxylin A and hispidulin, compounds which are abundant in both <jats:italic>Scutellaria</jats:italic> and liverwort species, are important lead compounds for the treatment of ischemic cerebrovascular disease. Their enzymatic synthesis requires an <jats:italic>O</jats:italic>‐methyltransferase able to interact with the related flavonoid's 6‐<jats:styled-content style="fixed-case">OH</jats:styled-content> group, but such an enzyme has yet to be identified in plants. Here, the gene encoding an <jats:italic>O</jats:italic>‐methyltransferase (designated PaF6<jats:styled-content style="fixed-case">OMT</jats:styled-content>) was isolated from the liverwort species <jats:italic>Plagiochasma appendiculatum</jats:italic>. A test of alternative substrates revealed that its strongest preferences were baicalein and scutellarein, which were converted into, respectively, oroxylin A and hispidulin. Allowed a sufficient reaction time, the conversion rate of these two substrates was, respectively, 90% and 100%. PaF6<jats:styled-content style="fixed-case">OMT</jats:styled-content> offers an enzymatic route to the synthesis of oroxylin A and hispidulin.</jats:p>