Structure-activity relationship of insecticidal okaramine

May 25, 2018

Biosynthetic research clarified what part of okaramine confer insecticidal properties

RIKEN CSRS researchers, in collaboration with Kindai University and Osaka Prefecture University, have succeeded in identifying the portion of the chemical structure of okaramine, a substance produced by filamentous fungi, that gives it its insecticidal activity.

Produced by Penicillium fungi, okaramine affects glutamate-gated chloride channel (GluCl) presents only in invertebrates. By genetic engineering of the fungus, researchers were able to collect biosynthetic intermediates that are usually difficult to obtain under the normal culture conditions and investigated their action on GluCl. They found that 1,4-dihydroazocine and N-aliphatic group attached to the indole is indispensable to the biological activity of okaramine.

These results are expected to contribute to the development of new okaramine-based insecticides that are friendly to humans and animals.

Original article
ACS Chemical Biology doi:10.1021/acschembio.7b00878
N. Kato, S. Furutani, J. Otaka, A. Noguchi, K. Kinugasa, K. Kai, H. Hayashi, M. Ihara, S. Takahashi, K. Matsuda, H. Osada,
"Biosynthesis and structure-activity relationship studies of okaramines that target insect glutamate-gated chloride channels".
Naoki Kato; Research Scientist
Natural Product Biosynthesis Research Unit
Hiroyuki Osada; Group Director
Chemical Biology Research Group