Detection of conserved microbe-associated molecular patterns (MAMPs), such as bacterial flagellin, is the first line of active defense in plants against pathogenic invaders. Successful pathogens must subvert this immune response to grow to high population density and cause disease. Flagellin from the bacterial pathogen Pseudomonas was the first identified bacterial MAMP and many species across the plant kingdom have sensitive perception systems for detecting the 22-amino acid epitope known as flg22. Tomato and several other solanaceous plants are also able to independently detect a second epitope of flagellin known as flgII-28. This chapter details four experimental protocols to identify and confirm the immune response-eliciting activity of flagellin and putative MAMPs with focus on the Pseudomonas-tomato pathosystem.
Keywords: Flagellin; Microbe-associated molecular patterns (MAMPs); Pattern-triggered immunity (PTI); Pseudomonas syringae; flg22; flgII-28.