The present invention relates to isolated nucleic acid molecules encoding
a type III--secreted bacterial protein capable of modifying a cell death
pathway in a plant cell. One aspect of the present invention involves an
isolated nucleic acid molecule having a nucleotide sequence that encodes
the HopPtoD2 protein of Pseudomonas syringae pv. syringae DC 3000.
Expression vectors, host cells, and transgenic plants which include the
DNA molecules of the present invention are also disclosed. The nucleic
acid molecules of the present invention can be used to impart disease
resistance to a plant and to make a plant hypersusceptible to
colonization by nonpathogenic bacteria.