Data from: Cytochrome P450 and O-methyltransferase catalyze the final steps in the biosynthesis of the anti-addictive alkaloid ibogaine from Tabernanthe iboga

Monoterpenoid indole alkaloids (MIAs) are a large (ca. 3000 members) and
structurally diverse class of metabolites restricted to a limited number
of plant families in the order Gentianales. Tabernanthe iboga or iboga
(Apocynaceae) is native to western equatorial Africa and has been used in
traditional medicine for centuries. Howard Lotsof is credited with
bringing iboga to the attention of Western medicine through his accidental
discovery that iboga can alleviate opioid withdrawal symptoms. Since this
observation, iboga has been investigated for its use in the general
management of addiction. We were interested in elucidating ibogaine
biosynthesis to understand the unique reaction steps en route to ibogaine.
Furthermore, because ibogaine is currently sourced from plant material,
these studies may help improve the ibogaine supply chain through synthetic
biology approaches. Here we used next-generation sequencing to generate
the first iboga transcriptome, and leveraged homology guided gene discovery
to identify the penultimate hydroxylase and final O-methyltransferase steps
in ibogaine biosynthesis, herein named ibogamine 10-hydroxylase (I10H) and
noribogaine 10-O-methyltransferase (N10OMT). Heterologous expression in
Saccharomyces cerevisiae (I10H) or Escherichia coli (N10OMT) and
incubation with putative precursors, along with HPLC–MS analysis, confirmed
the predicted activities of both enzymes. Moreover, high expression levels
of their transcripts were detected in ibogaine-accumulating plant tissues.
These discoveries coupled with our publicly available iboga transcriptome
will contribute to additional gene discovery efforts and could lead to the
stabilization of the global ibogaine supply chain and to the development
of ibogaine as a treatment for addiction.