INSECT-SYMBIOTIC BACTERIA INHIBITORY TO XYLELLA FASTIDIOSA IN SHARPSHOOTERS: TOXIC PEPTIDES AGAINST XYLELLA

• Author(s): Cooksey, Donald; Miller, Thomas; Bextine, Blake; Lampe, David; Lauzon, Carol;
• Abstract: Eleven strains of the pathogen, Xylella fastidiosa, and the glassy-winged sharpshooter (GWSS) gut bacterium, Alcaligenes xylosoxidans denitrificans, were screened for sensitivity to 41antimicrobial peptides (in addition to 18 screened previously), and more detailed studies of effective inhibitory concentrations of these peptides were conducted. Of 28 additional peptides found to have toxicity toward X. fastidiosa, 25 were also toxic to Alcaligenes, leaving three as additional candidates for engineering of this GWSS gut bacterium in addition to one found last year. Genes encoding these peptides are being designed and constructed with appropriate promoters and signal peptides for expression and secretion by Alcaligenes. Another 89 antimicrobial peptides derived from a combinatorial peptide library were also recently obtained and will be tested against Xylella and Alcaligenes xylosoxidans denitrificans. The results support the idea that this glassy-winged sharpshooter gut bacterium could be engineered to produce a peptide with toxicity toward the Pierces disease pathogen.
• Publication Date: Aug 2003
• Journal: 2003 Pierce's Disease Research Symposium