Genetically Engineered Yeast Expressing a Lytic Peptide from Bee Venom (Melittin) Kills Symbiotic Protozoa in the Gut of Formosan Subterranean Termites.

Pedro L Oliveira,Claudia Husseneder,Jennifer R Donaldson,Lane D Foil

doi:10.1371/journal.pone.0151675

Pedro L Oliveira, Claudia Husseneder + Show 2 more

Open Access

https://doi.org/10.1371/journal.pone.0151675

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Journal: PloS one	Publication Date: Mar 17, 2016
Citations: 13	License type: CC BY 4.0

Affiliation: Louisiana State University Agricultural Center

Abstract

The Formosan subterranean termite, Coptotermes formosanus Shiraki, is a costly invasive urban pest in warm and humid regions around the world. Feeding workers of the Formosan subterranean termite genetically engineered yeast strains that express synthetic protozoacidal lytic peptides has been shown to kill the cellulose digesting termite gut protozoa, which results in death of the termite colony. In this study, we tested if Melittin, a natural lytic peptide from bee venom, could be delivered into the termite gut via genetically engineered yeast and if the expressed Melittin killed termites via lysis of symbiotic protozoa in the gut of termite workers and/or destruction of the gut tissue itself. Melittin expressing yeast did kill protozoa in the termite gut within 56 days of exposure. The expressed Melittin weakened the gut but did not add a synergistic effect to the protozoacidal action by gut necrosis. While Melittin could be applied for termite control via killing the cellulose-digesting protozoa in the termite gut, it is unlikely to be useful as a standalone product to control insects that do not rely on symbiotic protozoa for survival.

Highlights

The Formosan subterranean termite (FST), Coptotermes formosanus Shiraki, is a costly invasive urban pest in warm areas of high humidity, approximately 35° north and south of the equator, which includes the southeastern United States [1]
Gut protozoa are vital for the survival of the termite colony since they facilitate digestion of lignocellulose, i.e., the major component in the diet of subterranean termites; loss of protozoa leads to death from starvation [4, 5, 6]
When lytic peptide expressing yeast was fed to Formosan subterranean termites in a bait, workers lost all their gut protozoa within three weeks and the termite lab colonies died within two weeks thereafter [13]

Summary

Introduction

The Formosan subterranean termite (FST), Coptotermes formosanus Shiraki, is a costly invasive urban pest in warm areas of high humidity, approximately 35° north and south of the equator, which includes the southeastern United States [1]. When lytic peptide expressing yeast was fed to Formosan subterranean termites in a bait, workers lost all their gut protozoa within three weeks and the termite lab colonies died within two weeks thereafter [13].

Results

Conclusion