Location: Emerging Pests and Pathogens Research
Title: Characterization of novel factors modulating pseudomonas syringae pv. tomato DC3000 pathogenicityAuthor
WAN, LINGWEI - Cornell University | |
Karp, Mary Ann | |
Stodghill, Paul | |
Filiatrault, Melanie |
Submitted to: Meeting Abstract
Publication Type: Abstract Only Publication Acceptance Date: 8/16/2022 Publication Date: N/A Citation: N/A Interpretive Summary: Technical Abstract: Pseudomonas syringae must successfully transition from the leaf surface to the apoplast environment to cause disease. One protein important for P. syringae to cause disease is a carbonic anhydrase, cynT. To identify how cynT impacts virulence we performed global transcriptome profiling to compare gene expression of a cynT mutant to wild-type. cynT impacted expression of 129 genes when grown in rich media, and 748 genes when grown in minimal media. One cluster of genes whose expression was regulated by cynT was srfABC. The srfABC gene cluster is widely conserved in many bacteria and is associated with pathogenicity, colonization, penetration and cytotoxicity in some bacteria, but the specific roles of the genes are not known. To investigate the role of srfBC in P. syringe we generated deletion mutants. When dipped or syringe inoculated on tomatoes, srfB and srfC mutants showed no symptoms or in vivo bacterial growth after 7 days compared to wild type indicating srfBC is required for virulence. The mutants were also not able to induce a hypersensitivity response on Nicotiana benthamiana. Preliminary translocation assays showed that srfB and srfC mutants were not able to translocate the effector protein AvrPto into host cells, suggesting the type III secretion system is disrupted in the mutants. Using a translocation assay, we found that SrfB and SrfC are not secreted into host cells. Current studies are focused on investigating if SrfB and SrfC are secreted by P. syringae into the apoplast and if SrfB and/or SrfC are bacterial toxins. |