Fig. 1: The proposed biosynthesis pathway for strychnine and brucine.

The partial biosynthetic pathway was predicted on the basis of previous radioisotopic feeding experiments. OPP, pyrophosphate; GPP, geranyl pyrophosphate.

The partial biosynthetic pathway was predicted on the basis of previous radioisotopic feeding experiments. OPP, pyrophosphate; GPP, geranyl pyrophosphate.