Bioengineering

We design and validate plant immune receptors with new recognition specificities — receptors that recognise pathogen molecules they did not evolve to see. Each engineering effort is a hypothesis about how immune biology works; success and failure feed back into the discovery work.

NLR–nanobody fusions

Fusing a nanobody (a small antibody-derived binding domain) to an NLR converts the receptor's recognition specificity to whatever the nanobody binds. We demonstrated this approach using nanobodies raised against fluorescent proteins, showing that the engineered receptors trigger immune responses in Nicotiana benthamiana when the target antigen is present (Kourelis et al., Science 2023). The principle generalises: any antigen with a nanobody becomes a candidate target.

Made-to-order protease decoys

Some immune receptors guard host proteins that pathogens attack. Engineering the guarded protein to become attackable by new effectors — or to attack new effectors — extends the receptor's recognition range. Recent work converted divergent Rcr3 protease orthologs into functional immune co-receptors (Kourelis et al., Plant Cell 2024) and demonstrated late-blight resistance via an EpiC2B-insensitive protease (Schuster et al., Plant Biotechnology Journal 2023).

Allelic compatibility and effector swapping

Receptors and their cognate effectors evolve together. By analysing allelic compatibility across receptor variants (Bentham et al., Plant Cell 2023), we map which receptor scaffolds tolerate which kinds of effector substitution — directly informing where engineering can succeed.

Network engineering for durability

Single-receptor engineering produces narrow resistance that pathogens evolve around. Engineering at the network level — combining multiple receptors with complementary specificities and shared helper requirements — produces resistance that is harder to defeat. This thread is in active development.