TY - JOUR
T1 - The Pseudomonas aeruginosa accessory genome elements influence virulence towards Caenorhabditis elegans
AU - Vasquez-Rifo, Alejandro
AU - Veksler-Lublinsky, Isana
AU - Cheng, Zhenyu
AU - Ausubel, Frederick M.
AU - Ambros, Victor
N1 - Publisher Copyright:
© 2019 The Author(s).
PY - 2019/12/10
Y1 - 2019/12/10
N2 - Background: Multicellular animals and bacteria frequently engage in predator-prey and host-pathogen interactions, such as the well-studied relationship between Pseudomonas aeruginosa and the nematode Caenorhabditis elegans. This study investigates the genomic and genetic basis of bacterial-driven variability in P. aeruginosa virulence towards C. elegans to provide evolutionary insights into host-pathogen relationships. Results: Natural isolates of P. aeruginosa that exhibit diverse genomes display a broad range of virulence towards C. elegans. Using gene association and genetic analysis, we identify accessory genome elements that correlate with virulence, including both known and novel virulence determinants. Among the novel genes, we find a viral-like mobile element, the teg block, that impairs virulence and whose acquisition is restricted by CRISPR-Cas systems. Further genetic and genomic evidence suggests that spacer-targeted elements preferentially associate with lower virulence while the presence of CRISPR-Cas associates with higher virulence. Conclusions: Our analysis demonstrates substantial strain variation in P. aeruginosa virulence, mediated by specific accessory genome elements that promote increased or decreased virulence. We exemplify that viral-like accessory genome elements that decrease virulence can be restricted by bacterial CRISPR-Cas immune defense systems, and suggest a positive, albeit indirect, role for host CRISPR-Cas systems in virulence maintenance.
AB - Background: Multicellular animals and bacteria frequently engage in predator-prey and host-pathogen interactions, such as the well-studied relationship between Pseudomonas aeruginosa and the nematode Caenorhabditis elegans. This study investigates the genomic and genetic basis of bacterial-driven variability in P. aeruginosa virulence towards C. elegans to provide evolutionary insights into host-pathogen relationships. Results: Natural isolates of P. aeruginosa that exhibit diverse genomes display a broad range of virulence towards C. elegans. Using gene association and genetic analysis, we identify accessory genome elements that correlate with virulence, including both known and novel virulence determinants. Among the novel genes, we find a viral-like mobile element, the teg block, that impairs virulence and whose acquisition is restricted by CRISPR-Cas systems. Further genetic and genomic evidence suggests that spacer-targeted elements preferentially associate with lower virulence while the presence of CRISPR-Cas associates with higher virulence. Conclusions: Our analysis demonstrates substantial strain variation in P. aeruginosa virulence, mediated by specific accessory genome elements that promote increased or decreased virulence. We exemplify that viral-like accessory genome elements that decrease virulence can be restricted by bacterial CRISPR-Cas immune defense systems, and suggest a positive, albeit indirect, role for host CRISPR-Cas systems in virulence maintenance.
KW - Accessory genome
KW - C. elegans
KW - CRISPR-Cas
KW - P. aeruginosa
KW - Virulence
UR - http://www.scopus.com/inward/record.url?scp=85076344557&partnerID=8YFLogxK
U2 - 10.1186/s13059-019-1890-1
DO - 10.1186/s13059-019-1890-1
M3 - Article
AN - SCOPUS:85076344557
SN - 1474-7596
VL - 20
JO - Genome Biology
JF - Genome Biology
IS - 1
M1 - 270
ER -