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ARS Home » Pacific West Area » Parlier, California » San Joaquin Valley Agricultural Sciences Center » Crop Diseases, Pests and Genetics Research » Research » Publications at this Location » Publication #383934

Research Project: Identification of Novel Management Strategies for Key Pests and Pathogens of Grapevine with Emphasis on the Xylella Fastidiosa Pathosystem

Location: Crop Diseases, Pests and Genetics Research

Title: Differential epigenetic modifications among Xylella fastidiosa strains correlate with type I restriction-modification system variation

item O'Leary, Michael
item Burbank, Lindsey
item Stenger, Drake

Submitted to: American Phytopathological Society Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 5/20/2021
Publication Date: 8/2/2021
Citation: O'Leary, M.L., Burbank, L.P., Stenger, D.C. 2021. Differential epigenetic modifications among Xylella fastidiosa strains correlate with type I restriction-modification system variation. American Phytopathological Society Abstracts.

Interpretive Summary:

Technical Abstract: Xylella fastidiosa is a bacterial plant pathogen with genetically distinct subspecies which collectively cause disease in diverse host plants. Genomes of X. fastidiosa strains are enriched in genes encoding restriction-modification systems, which methylate native DNA and cut unmethylated DNA at specific sequence motifs. Restriction-modification systems can provide defense against phages and limit horizontal gene transfer between closely related strains, but can also influence expression of virulence-related genes in some animal-pathogenic bacteria. Type I restriction-modification systems function as a protein complex, with sequence specificity determined by the two target recognition domains of a specificity subunit, HsdS. Analysis of 117 X. fastidiosa strains reveals most strains contain three conserved type I restriction-modification systems, while strains of subspecies multiplex and pauca contain a fourth system. Up to twenty-two unique hsdS alleles were identified per system; in total, at least 30 aggregate hsdS allele profiles were identified across X. fastidiosa strains, suggesting differential genomic methylation patterns exist across strains. Genomic methylation profiles of twelve X. fastidiosa strains were determined and contain two to four methylated motifs characteristic of type I restriction-modification recognition sites. Variation among these motif sequences was identified both within and between X. fastidiosa subspecies and is consistent with variation among hsdS alleles.