In a press release posted on the Cardiff University website on Monday, Professor Rudolf Allemann discusses his work into the biosynthesis of insect-repelling scent molecules.
By using an enzyme, ((S)-germacrene D synthase), known to produce natural insect-repelling scents, the group was able to synthesise a number of alternative molecules, which also have distinctive smells. They then tested these molecules on the grain aphid Sitobion avenae to see how effective they were as insect repellents.
In all cases but one, the molecules were found to repel the insects. In the one case that didn’t they saw a complete reversal in the behaviour of the aphids, which were attracted to the scent. This has the potential of being used in a trap-and-kill device.
In the press release, Professor Alleman stated, “The difficulty is that scientifically smell molecules are often extremely volatile, chemically unstable and expensive to re-create. This means that, until now, progress has been extremely slow in recreating smells that are similar to the original.
“Through the power of novel biochemical techniques we have been able to make insect repellent smell molecules which are structurally different but functionally similar to the original.”
This work is a great example of using nature’s catalysts, enzymes, to produce useful compounds that would otherwise be inaccessible using traditional chemical synthetic methods.