Association of a Xylella fastidiosa protein with chlorosis induction in Chenopodium quinoa leaves

• Author(s): Bruening, George; Buzayan, J.; Civerolo, Ed; Feldstein, Paul; Lee, Youn-Hyung; Re, E.;
• Abstract: Xf cells were held at room temperature, or at 100degreeC for 20 min and cooled, and infiltrated into Cq leaves. Chlorosis, confined to the infiltrated area, developed within 48 hr. High-speed centrifugation collected the elicitor activity in the precipitate. Suspended precipitate, incubated with any of three proteases, lost elicitor activity. Sodium dodecyl sulfate (SDS) extraction of the precipitate retained elicitor activity and simplified the SDS-gel electrophoresis pattern of the precipitate. Mass spectrometry of a trypsin-treated gel band corresponding to protein with apparent molecular weight about 41,000 identified amino acid sequences corresponding to about 40% of the Xf outer membrane protein mopB. Material extracted from the same band position in a parallel, unstained gel lane induced chlorosis when infiltrated into Cq leaves. Our results suggest that Xf mopB is a heat stable elicitor of chlorosis in Cq leaves.
• Publication Date: Jun 2002
• Journal: Phytopathology