Peter Metcalf and colleagues at the University of Auckland say their findings help explain the resilience of insect viruses and might aid in the development of insecticides and novel therapeutics.

Cypoviruses are hard to kill because hundreds of the infectious viral particles are embedded in tiny protein crystals called polyhedra. The polyhedra structure resembles some viral outer shells or "capsid" proteins but is unique in other ways. And the resulting ultrastable, sealed crystals shield the virus particles from environmental damage.

The researchers also report discovering bound nucleotides within the crystals, raising the possibility that polyhedra-like nanoparticles could be used as storage and delivery devices for small molecules or drugs.

The study is detailed in the journal Nature.