Abstract
An elicitor (PiPE) from the oomycete Phytophthora infestans (Pi) stimulates the hypersensitive response (HR) in potato. The PiPE, purified by anion-exchange chromatography from a water-soluble extract of Pi caused cell death, characteristic of HR, and enhanced active oxygen species (AOS) generation in tuber tissues. The sequence of the PiPE cDNA derived by PCR had homologous domain to fructose 1,6 bisphosphate aldolase (FBA) gene. To demonstrate that the PiPE cDNA encodes an active elicitor, we expressed PiPE in Echerichia coli, high five insect cells and purified the recombinant protein. His-PiPE induced HR, browning and generation of AOS in potato tissues. The PiPE was produced in the germination fluid from Pi and was located in the cell wall of Pi. The role of PiPE is discussed in the induction of HR in incompatible and compatible interaction between Pi and potato cells.
