Forage Science

“Nano-machine” holds promise as biopesticide delivery vehicle

25 October 2018
“Nano-machine” holds promise as biopesticide delivery vehicle

A “nano-machine” that kills grass grubs by injecting toxin into their cells may become a new delivery mechanism for other biopesticides.

AgResearch scientist Mark Hurst discovered the nano-machine, or anti-feeding prophage (Afp), when uncovering the highly virulent AGR96X strain of Serratia proteamaculans responsible for swiftly knocking down grass grubs (see Next Generation Bio-Pesticides Winter 2018).

The Afp produced by grass grub active Serratia species, including AGR96X, is called a nano-machine because it acts like a machine, transporting the toxin and injecting it into grass grub cells, killing the larvae. What is exciting for scientists developing biopesticides is the Afp could potentially be manipulated to transport and inject other toxins into other insects, and so be a versatile delivery vehicle.

“Unlike many protein-based toxins, the Afp is very stable. It remains active at high temperatures (up to 45°C) and can tolerate a broad range of solvents and pH conditions,” says Dr Mark Hurst, the scientist leading the research programme.

“This, along with the fact it contains no DNA and its extremely small size, makes it ideal for delivering insect toxins.”

Dr Hurst has recently gained MBIE Smart Ideas funding to investigate the possibility of manipulating Afp to target other insect species, offering a viable alternative for insect control.

“Based on our previous success in expressing and manipulating the AfP, it’s likely we can reprogram this unique nano-machine,” says Dr Hurst.