Chinese researchers announced on Wednesday that they have coaxed genetically engineered silkworms to synthesise spider silk, yielding fibre about six times tougher than Kevlar which is used in bullet-proof vests.

Their work represents the first successful production of full-length spider silk fibre using silkworms and demonstrates a technique the scientists believe could be used to make an environment-friendly alternative to synthetic commercial fibre such as nylon.

“Silkworm silk is presently the only animal silk fibre commercialised on a large scale with well-established rearing techniques,” said Junpeng Mi, a research scholar at the College of Biological Science and Medical Engineering at Donghua University, and lead author of the study. Genetically engineered silkworms designed to produce spider silk, Mi said, could enable low-cost and large-scale commercial production.

“We are confident that large-scale commercialisation is on the horizon,” Mi said in a media release, accompanying the publication of the study in the peer-reviewed research journal Matter.

Scientists have for years eyed spider silk as a potential strategic resource. Spider silk fibre could be used to create garments, innovative tougher bullet-proof vests, as well as other materials for use in biomedical engineering or aerospace technology. “The exceptionally high mechanical performance of the fibre produced in the study holds significant promise,” Mi said. “This type of fibre could also be used as surgical sutures.”

Mi and his team introduced spider silk protein genes into the genetic material of silkworms, enabling the silkworms to produce spider silk. They had to use additional biological tricks to ensure that spider silk proteins made by the silkworms would interact properly with proteins in the silkworm glands leading to a proper spinning process.

The scientists now plan to use information about the toughness and strength of the spider silk fibre to develop genetically engineered silkworms.