Fusion protein-based biopesticides for sustainable crop protection

This research and development programme is intended to result in the introduction of a novel, environmentally beneficial biopesticide to market, as a replacement for older pesticides being removed from use under legislation on pesticide safety introduced by the EC. The biopesticide is based on fusion protein technology invented and developed collaboratively by the Food and Environment Research Agency (Fera), York and Durham University. This allows selected toxins from arthropods, which have no toxicity towards higher animals, to be combined with a carrier protein that makes them orally toxic to invertebrates, whereas they would normally only be effective when injected into a prey organism by a predator. The fusion protein, containing both the toxin and the carrier is produced as a recombinant protein in a microbial expression system, which can be scaled up for industrial production.Research previously funded under LINK programmes has resulted in a best candidate fusion protein ( FP4 ) which has been evaluated for commercial production. However, in the present programme it is intended to use a 2010 best candidate fusion protein with improved insecticidal activity ( FP5 ), which will be more likely to result in a commercially viable product. In order to bring this technology to market, the laboratory scale process for protein production must be optimised, to decrease production costs. Yield of recombinant protein per volume of microbial culture is a major factor in the final cost of product, and therefore the initial stage of the programme will be to improve the existing expression clones. Experience with an earlier fusion protein has shown that improvements in yield of product can be made by the introduction of extra copies of gene sequence into the yeast expression host, and this will be carried out for the 2010 best candidate . The resulting yeast clones will be screened for protein production, and the best clones will be selected and taken forward in the programme. The aim will be to produce recombinant protein on a 1g per litre of microbial culture scale.If a fusion protein-based biopesticide is to be introduced as a commercial product, testing will be necessary to assess its effects on non-target organisms. The toxin selected for this programme has been shown to be non-toxic to higher animals. However, further testing of the fusion protein will need to be carried out by other partners in the programme. A more significant potential problem is effects on beneficial invertebrates, such as the predators and parasites that attack crop pests, pollinators such as bees, and earthworms. Earlier experiments with the best candidate fusion protein, carried out under a previously funded LINK programme, have suggested that fusion proteins do not cause adverse effects on beneficial organisms. However, more extensive testing of the 2010 best candidate fusion protein will be required to confirm absence of any adverse environmental impact. The academic partners will carry out preliminary work in this area, using a service provided by Newcastle University, prior to more extensive testing required to meet regulatory requirements, which will be addressed by industrial partners.Finally, further development of fusion proteins will be carried out by Durham and Fera, separately from the present programme. If fusion proteins with higher insecticidal activity or other desirable properties are developed, these will be made available for development by industrial partners in the TSB programme.